From f2959bf6db3442707b8e1d40a206fb28067a9c91 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Sat, 29 Nov 2025 19:45:33 +0100
Subject: [PATCH 01/57] refactor `spec` into a separate submodule

---
 minimum_versions/environments/__init__.py |  2 +
 minimum_versions/environments/conda.py    | 43 ++++++++++++++++
 minimum_versions/environments/spec.py     | 23 +++++++++
 minimum_versions/spec.py                  | 63 -----------------------
 4 files changed, 68 insertions(+), 63 deletions(-)
 create mode 100644 minimum_versions/environments/__init__.py
 create mode 100644 minimum_versions/environments/conda.py
 create mode 100644 minimum_versions/environments/spec.py
 delete mode 100644 minimum_versions/spec.py

diff --git a/minimum_versions/environments/__init__.py b/minimum_versions/environments/__init__.py
new file mode 100644
index 0000000..945c42d
--- /dev/null
+++ b/minimum_versions/environments/__init__.py
@@ -0,0 +1,2 @@
+from minimum_versions.environments.conda import parse_conda_environment  # noqa: F401
+from minimum_versions.environments.spec import Spec, compare_versions  # noqa: F401
diff --git a/minimum_versions/environments/conda.py b/minimum_versions/environments/conda.py
new file mode 100644
index 0000000..932351a
--- /dev/null
+++ b/minimum_versions/environments/conda.py
@@ -0,0 +1,43 @@
+import yaml
+from rattler import Version
+
+from minimum_versions.environments.spec import Spec
+
+
+def parse_spec(spec_text):
+    warnings = []
+    if ">" in spec_text or "<" in spec_text:
+        warnings.append(
+            f"package must be pinned with an exact version: {spec_text!r}. Using the version as an exact pin instead."
+        )
+
+        spec_text = spec_text.replace(">", "").replace("<", "")
+
+    if "=" in spec_text:
+        name, version_text = spec_text.split("=", maxsplit=1)
+        version = Version(version_text)
+        segments = version.segments()
+
+        if (len(segments) == 3 and segments[2] != [0]) or len(segments) > 3:
+            warnings.append(
+                f"package should be pinned to a minor version (got {version})"
+            )
+    else:
+        name = spec_text
+        version = None
+
+    return Spec(name, version), (name, warnings)
+
+
+def parse_conda_environment(data):
+    env = yaml.safe_load(data)
+
+    specs = []
+    warnings = []
+    for dep in env["dependencies"]:
+        spec, warnings_ = parse_spec(dep)
+
+        specs.append(spec)
+        warnings.append(warnings_)
+
+    return specs, warnings
diff --git a/minimum_versions/environments/spec.py b/minimum_versions/environments/spec.py
new file mode 100644
index 0000000..a244567
--- /dev/null
+++ b/minimum_versions/environments/spec.py
@@ -0,0 +1,23 @@
+from dataclasses import dataclass
+
+from rattler import Version
+
+
+@dataclass
+class Spec:
+    name: str
+    version: Version | None
+
+
+def compare_versions(environments, policy_versions, ignored_violations):
+    status = {}
+    for env, specs in environments.items():
+        env_status = any(
+            (
+                spec.name not in ignored_violations
+                and spec.version > policy_versions[spec.name].version
+            )
+            for spec in specs
+        )
+        status[env] = env_status
+    return status
diff --git a/minimum_versions/spec.py b/minimum_versions/spec.py
deleted file mode 100644
index a7c72d5..0000000
--- a/minimum_versions/spec.py
+++ /dev/null
@@ -1,63 +0,0 @@
-from dataclasses import dataclass
-
-import yaml
-from rattler import Version
-
-
-@dataclass
-class Spec:
-    name: str
-    version: Version | None
-
-    @classmethod
-    def parse(cls, spec_text):
-        warnings = []
-        if ">" in spec_text or "<" in spec_text:
-            warnings.append(
-                f"package must be pinned with an exact version: {spec_text!r}. Using the version as an exact pin instead."
-            )
-
-            spec_text = spec_text.replace(">", "").replace("<", "")
-
-        if "=" in spec_text:
-            name, version_text = spec_text.split("=", maxsplit=1)
-            version = Version(version_text)
-            segments = version.segments()
-
-            if (len(segments) == 3 and segments[2] != [0]) or len(segments) > 3:
-                warnings.append(
-                    f"package should be pinned to a minor version (got {version})"
-                )
-        else:
-            name = spec_text
-            version = None
-
-        return cls(name, version), (name, warnings)
-
-
-def parse_environment(text):
-    env = yaml.safe_load(text)
-
-    specs = []
-    warnings = []
-    for dep in env["dependencies"]:
-        spec, warnings_ = Spec.parse(dep)
-
-        specs.append(spec)
-        warnings.append(warnings_)
-
-    return specs, warnings
-
-
-def compare_versions(environments, policy_versions, ignored_violations):
-    status = {}
-    for env, specs in environments.items():
-        env_status = any(
-            (
-                spec.name not in ignored_violations
-                and spec.version > policy_versions[spec.name].version
-            )
-            for spec in specs
-        )
-        status[env] = env_status
-    return status

From cf5c4c0beb1576e579305908876461e3596cffb6 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Sat, 29 Nov 2025 19:52:03 +0100
Subject: [PATCH 02/57] dispatch by kind

---
 minimum_versions/environments/__init__.py | 14 ++++++++++++++
 minimum_versions/main.py                  | 13 +++++--------
 2 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/minimum_versions/environments/__init__.py b/minimum_versions/environments/__init__.py
index 945c42d..d1c607e 100644
--- a/minimum_versions/environments/__init__.py
+++ b/minimum_versions/environments/__init__.py
@@ -1,2 +1,16 @@
 from minimum_versions.environments.conda import parse_conda_environment  # noqa: F401
 from minimum_versions.environments.spec import Spec, compare_versions  # noqa: F401
+
+kinds = {
+    "conda": parse_conda_environment,
+}
+
+
+def parse_environment(specifier: str) -> list[Spec]:
+    kind, path = specifier.split(":", maxsplit=1)
+
+    parser = kinds.get(kind)
+    if parser is None:
+        raise ValueError(f"Unknown kind {kind!r}, extracted from {specifier!r}.")
+
+    return parser(path)
diff --git a/minimum_versions/main.py b/minimum_versions/main.py
index 0f3ffc0..c49e23b 100644
--- a/minimum_versions/main.py
+++ b/minimum_versions/main.py
@@ -1,5 +1,5 @@
 import datetime
-import pathlib
+import os.path
 import sys
 
 import rich_click as click
@@ -8,10 +8,10 @@
 from rich.table import Table
 from tlz.itertoolz import concat
 
+from minimum_versions.environments import compare_versions, parse_environment
 from minimum_versions.formatting import format_bump_table
 from minimum_versions.policy import find_policy_versions, parse_policy
 from minimum_versions.release import fetch_releases
-from minimum_versions.spec import compare_versions, parse_environment
 
 click.rich_click.SHOW_ARGUMENTS = True
 
@@ -29,11 +29,7 @@ def main():
 
 
 @main.command()
-@click.argument(
-    "environment_paths",
-    type=click.Path(exists=True, readable=True, path_type=pathlib.Path),
-    nargs=-1,
-)
+@click.argument("environment_paths", type=str, nargs=-1)
 @click.option("--today", type=parse_date, default=None)
 @click.option("--policy", "policy_file", type=click.File(mode="r"), required=True)
 def validate(today, policy_file, environment_paths):
@@ -42,7 +38,8 @@ def validate(today, policy_file, environment_paths):
     policy = parse_policy(policy_file)
 
     parsed_environments = {
-        path.stem: parse_environment(path.read_text()) for path in environment_paths
+        path.rsplit(os.path.sep, maxsplit=1)[-1]: parse_environment(path)
+        for path in environment_paths
     }
 
     warnings = {

From 9e1e9ecd3afae5d6c0c4d193828d90273e88625e Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Sat, 29 Nov 2025 19:53:08 +0100
Subject: [PATCH 03/57] default the kind to `conda`

---
 minimum_versions/environments/__init__.py | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/minimum_versions/environments/__init__.py b/minimum_versions/environments/__init__.py
index d1c607e..072b46f 100644
--- a/minimum_versions/environments/__init__.py
+++ b/minimum_versions/environments/__init__.py
@@ -7,7 +7,12 @@
 
 
 def parse_environment(specifier: str) -> list[Spec]:
-    kind, path = specifier.split(":", maxsplit=1)
+    split = specifier.split(":", maxsplit=1)
+    if len(split) == 1:
+        kind = "conda"
+        path = specifier
+    else:
+        kind, path = split
 
     parser = kinds.get(kind)
     if parser is None:

From 5a6b670074d148d666d41639cd70c4f4cabd2e63 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Sat, 29 Nov 2025 19:56:30 +0100
Subject: [PATCH 04/57] adapt the tests

---
 minimum_versions/tests/test_spec.py | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/minimum_versions/tests/test_spec.py b/minimum_versions/tests/test_spec.py
index 64b4252..df1c64d 100644
--- a/minimum_versions/tests/test_spec.py
+++ b/minimum_versions/tests/test_spec.py
@@ -1,7 +1,7 @@
 import pytest
 from rattler import Version
 
-from minimum_versions.spec import Spec
+from minimum_versions.environments import Spec, conda
 
 
 @pytest.mark.parametrize(
@@ -17,8 +17,8 @@
         ),
     ),
 )
-def test_spec_parse(text, expected_spec, expected_name, expected_warnings):
-    actual_spec, (actual_name, actual_warnings) = Spec.parse(text)
+def test_parse_conda_spec(text, expected_spec, expected_name, expected_warnings):
+    actual_spec, (actual_name, actual_warnings) = conda.parse_spec(text)
 
     assert actual_spec == expected_spec
     assert actual_name == expected_name

From 7eef3e5c40c97c8140cb039a2f4bd122db9e2c03 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Sat, 29 Nov 2025 20:02:43 +0100
Subject: [PATCH 05/57] configure project metadata

---
 pyproject.toml | 37 +++++++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)

diff --git a/pyproject.toml b/pyproject.toml
index bacf560..4a3f92c 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,3 +1,40 @@
+[project]
+name = "minimum-dependency-versions"
+authors = [
+  { name = "Justus Magin" },
+]
+license = "Apache-2.0"
+description = "Validate minimum dependency environments according to xarray's policy scheme"
+requires-python = ">=3.11"
+dependencies = [
+  "rich",
+  "rich-click",
+  "pyyaml",
+  "cytoolz",
+  "py-rattler",
+  "python-dateutil",
+  "jsonschema",
+]
+dynamic = ["version"]
+
+[project.urls]
+Repository = "https://github.com/xarray-contrib/minimum-dependency-versions"
+
+[build-system]
+requires = ["hatchling", "hatch-vcs"]
+build-backend = "hatchling.build"
+
+[tool.hatch]
+version.source = "vcs"
+
+[tool.hatch.metadata.hooks.vcs]
+
+[tool.hatch.build.targets.sdist]
+only-include = ["minimum_versions"]
+
+[tool.hatch.build.targets.wheel]
+only-include = ["minimum_versions"]
+
 [tool.ruff]
 target-version = "py39"
 builtins = ["ellipsis"]

From a20e075874cf2556459f4d388b0636b00f6c2d36 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Sat, 29 Nov 2025 21:28:35 +0100
Subject: [PATCH 06/57] add `manifest_path` to the cli options

---
 minimum_versions/environments/__init__.py |  8 +++++---
 minimum_versions/environments/conda.py    |  6 ++++--
 minimum_versions/main.py                  | 11 +++++++++--
 3 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/minimum_versions/environments/__init__.py b/minimum_versions/environments/__init__.py
index 072b46f..0faa7a2 100644
--- a/minimum_versions/environments/__init__.py
+++ b/minimum_versions/environments/__init__.py
@@ -1,4 +1,6 @@
-from minimum_versions.environments.conda import parse_conda_environment  # noqa: F401
+import pathlib
+
+from minimum_versions.environments.conda import parse_conda_environment
 from minimum_versions.environments.spec import Spec, compare_versions  # noqa: F401
 
 kinds = {
@@ -6,7 +8,7 @@
 }
 
 
-def parse_environment(specifier: str) -> list[Spec]:
+def parse_environment(specifier: str, manifest_path: pathlib.Path | None) -> list[Spec]:
     split = specifier.split(":", maxsplit=1)
     if len(split) == 1:
         kind = "conda"
@@ -18,4 +20,4 @@ def parse_environment(specifier: str) -> list[Spec]:
     if parser is None:
         raise ValueError(f"Unknown kind {kind!r}, extracted from {specifier!r}.")
 
-    return parser(path)
+    return parser(path, manifest_path)
diff --git a/minimum_versions/environments/conda.py b/minimum_versions/environments/conda.py
index 932351a..63a8884 100644
--- a/minimum_versions/environments/conda.py
+++ b/minimum_versions/environments/conda.py
@@ -1,3 +1,5 @@
+import pathlib
+
 import yaml
 from rattler import Version
 
@@ -29,8 +31,8 @@ def parse_spec(spec_text):
     return Spec(name, version), (name, warnings)
 
 
-def parse_conda_environment(data):
-    env = yaml.safe_load(data)
+def parse_conda_environment(path: pathlib.Path, manifest_path: None):
+    env = yaml.safe_load(pathlib.Path(path).read_text())
 
     specs = []
     warnings = []
diff --git a/minimum_versions/main.py b/minimum_versions/main.py
index c49e23b..23bb048 100644
--- a/minimum_versions/main.py
+++ b/minimum_versions/main.py
@@ -1,5 +1,6 @@
 import datetime
 import os.path
+import pathlib
 import sys
 
 import rich_click as click
@@ -30,15 +31,21 @@ def main():
 
 @main.command()
 @click.argument("environment_paths", type=str, nargs=-1)
+@click.option(
+    "--manifest-path",
+    "manifest_path",
+    type=click.Path(exists=True, path_type=pathlib.Path),
+    default=None,
+)
 @click.option("--today", type=parse_date, default=None)
 @click.option("--policy", "policy_file", type=click.File(mode="r"), required=True)
-def validate(today, policy_file, environment_paths):
+def validate(today, policy_file, manifest_path, environment_paths):
     console = Console()
 
     policy = parse_policy(policy_file)
 
     parsed_environments = {
-        path.rsplit(os.path.sep, maxsplit=1)[-1]: parse_environment(path)
+        path.rsplit(os.path.sep, maxsplit=1)[-1]: parse_environment(path, manifest_path)
         for path in environment_paths
     }
 

From 8f37fefc0ab67da678b5efff1f938abc734f08a9 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Sat, 29 Nov 2025 21:29:23 +0100
Subject: [PATCH 07/57] formatting

---
 minimum_versions/environments/conda.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/minimum_versions/environments/conda.py b/minimum_versions/environments/conda.py
index 63a8884..27dcfc0 100644
--- a/minimum_versions/environments/conda.py
+++ b/minimum_versions/environments/conda.py
@@ -10,7 +10,8 @@ def parse_spec(spec_text):
     warnings = []
     if ">" in spec_text or "<" in spec_text:
         warnings.append(
-            f"package must be pinned with an exact version: {spec_text!r}. Using the version as an exact pin instead."
+            f"package must be pinned with an exact version: {spec_text!r}."
+            " Using the version as an exact pin instead."
         )
 
         spec_text = spec_text.replace(">", "").replace("<", "")

From 9f9990e7944409f0c9ef662dfe65e26f44f1d306 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Sat, 29 Nov 2025 21:29:35 +0100
Subject: [PATCH 08/57] write the environment parsing for pixi envs

---
 minimum_versions/environments/__init__.py |   2 +
 minimum_versions/environments/pixi.py     | 102 ++++++++++++++++++++++
 2 files changed, 104 insertions(+)
 create mode 100644 minimum_versions/environments/pixi.py

diff --git a/minimum_versions/environments/__init__.py b/minimum_versions/environments/__init__.py
index 0faa7a2..a4df9d1 100644
--- a/minimum_versions/environments/__init__.py
+++ b/minimum_versions/environments/__init__.py
@@ -1,10 +1,12 @@
 import pathlib
 
 from minimum_versions.environments.conda import parse_conda_environment
+from minimum_versions.environments.pixi import parse_pixi_environment
 from minimum_versions.environments.spec import Spec, compare_versions  # noqa: F401
 
 kinds = {
     "conda": parse_conda_environment,
+    "pixi": parse_pixi_environment,
 }
 
 
diff --git a/minimum_versions/environments/pixi.py b/minimum_versions/environments/pixi.py
new file mode 100644
index 0000000..b3ec25f
--- /dev/null
+++ b/minimum_versions/environments/pixi.py
@@ -0,0 +1,102 @@
+import pathlib
+import re
+
+import tomllib
+from rattler import Version
+from tlz.dicttoolz import get_in, merge
+
+from minimum_versions.environments.spec import Spec
+
+_version_re = r"[0-9]+\.[0-9]+(?:\.[0-9]+|\.\*)"
+version_re = re.compile(f"(?P<version>{_version_re})")
+lower_pin_re = re.compile(rf">=(?P<version>{_version_re})$")
+tight_pin_re = re.compile(rf">=(?P<lower>{_version_re}),<(?P<upper>{_version_re})")
+
+
+def parse_spec(name, version_text):
+    # "*" => None
+    # "x.y.*" => "x.y"
+    # ">=x.y.0,<x.(y + 1).0" => "x.y" (+ warning)
+    # ">=x.y.*" => "x.y" (+ warning)
+
+    warnings = []
+    if version_text == "*":
+        raw_version = None
+    elif (match := version_re.match(version_text)) is not None:
+        raw_version = match.group("version")
+    elif (match := lower_pin_re.match(version_text)) is not None:
+        warnings.append(
+            f"package must be pinned with an exact version: {version_text!r}."
+            " Using the version as an exact pin instead."
+        )
+
+        raw_version = match.group("version")
+    elif (match := tight_pin_re.match(version_text)) is not None:
+        lower_pin = match.group("lower")
+        upper_pin = match.group("upper")
+
+        warnings.append(
+            f"lower pin {lower_pin!r} and upper pin {upper_pin!r} found."
+            " Using the lower pin for now, please convert to the standard x.y.* syntax."
+        )
+
+        raw_version = lower_pin
+    else:
+        raise ValueError(f"Unknown version format: {version_text}")
+
+    if raw_version is not None:
+        version = Version(raw_version.removesuffix(".*"))
+        segments = version.segments()
+        if (len(segments) == 3 and segments[2] != [0]) or len(segments) > 3:
+            warnings.append(
+                f"package should be pinned to a minor version (got {version})"
+            )
+    else:
+        version = raw_version
+
+    return Spec(name, version), (name, warnings)
+
+
+def parse_pixi_environment(name: str, manifest_path: pathlib.Path | None):
+    if manifest_path is None:
+        raise ValueError("--manifest-path is required for pixi environments.")
+
+    with manifest_path.open(mode="rb") as f:
+        data = tomllib.load(f)
+
+    if manifest_path.name == "pixi.toml":
+        pixi_config = data
+    else:
+        pixi_config = get_in(["pixi", "tool"], data, None)
+        if pixi_config is None:
+            raise ValueError(
+                f"The 'tool.pixi' section is missing from {manifest_path}."
+            )
+
+    environment_definitions = pixi_config.get("environments")
+    if environment_definitions is None:
+        raise ValueError("Can't find environments in the pixi config.")
+
+    all_features = pixi_config.get("feature")
+    if all_features is None:
+        raise ValueError("No features found in the pixi config.")
+
+    env = environment_definitions.get(name)
+    if env is None:
+        raise ValueError(f"Unknown environment: {name}")
+
+    features = [
+        get_in([feature, "dependencies"], all_features) for feature in env["features"]
+    ]
+
+    pins = merge(features)
+
+    specs = []
+    warnings = []
+    for name, pin in pins.items():
+        spec, warnings_ = parse_spec(name, pin)
+
+        specs.append(spec)
+        warnings.append(warnings_)
+
+    return specs, warnings

From 1c0c0eeb3bdd9655847d98e9f788157d29277f82 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Sun, 30 Nov 2025 15:46:55 +0100
Subject: [PATCH 09/57] raise a more descriptive error if no suitable releases
 were found

---
 minimum_versions/policy.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/minimum_versions/policy.py b/minimum_versions/policy.py
index 3d25bf2..a167c04 100644
--- a/minimum_versions/policy.py
+++ b/minimum_versions/policy.py
@@ -82,6 +82,8 @@ def minimum_version(self, today, package_name, releases):
         suitable_releases = [
             release for release in releases if is_suitable_release(release)
         ]
+        if not suitable_releases:
+            raise ValueError(f"Cannot find valid releases for {package_name}")
 
         policy_months = self.package_months.get(package_name, self.default_months)
 
@@ -90,6 +92,7 @@ def minimum_version(self, today, package_name, releases):
         index = bisect.bisect_left(
             suitable_releases, cutoff_date, key=lambda x: x.timestamp.date()
         )
+
         return suitable_releases[index - 1 if index > 0 else 0]
 
 

From fd070576f8af13b3254f4a8366e5a3463591e9f9 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Sun, 30 Nov 2025 15:47:53 +0100
Subject: [PATCH 10/57] filter out excluded packages before fetching releases

---
 minimum_versions/main.py | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/minimum_versions/main.py b/minimum_versions/main.py
index 23bb048..29cda01 100644
--- a/minimum_versions/main.py
+++ b/minimum_versions/main.py
@@ -7,7 +7,7 @@
 from rich.console import Console
 from rich.panel import Panel
 from rich.table import Table
-from tlz.itertoolz import concat
+from tlz.itertoolz import concat, unique
 
 from minimum_versions.environments import compare_versions, parse_environment
 from minimum_versions.formatting import format_bump_table
@@ -58,7 +58,11 @@ def validate(today, policy_file, manifest_path, environment_paths):
     }
 
     all_packages = list(
-        dict.fromkeys(spec.name for spec in concat(environments.values()))
+        unique(
+            spec.name
+            for spec in concat(environments.values())
+            if spec.name not in policy.exclude
+        )
     )
 
     package_releases = fetch_releases(policy.channels, policy.platforms, all_packages)

From f1e6de1efd06ab52fc675c408acc63c7b9e0b78f Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Sun, 30 Nov 2025 15:49:45 +0100
Subject: [PATCH 11/57] consider unpinned specs as not matching

---
 minimum_versions/environments/spec.py | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/minimum_versions/environments/spec.py b/minimum_versions/environments/spec.py
index a244567..f93fa94 100644
--- a/minimum_versions/environments/spec.py
+++ b/minimum_versions/environments/spec.py
@@ -15,7 +15,10 @@ def compare_versions(environments, policy_versions, ignored_violations):
         env_status = any(
             (
                 spec.name not in ignored_violations
-                and spec.version > policy_versions[spec.name].version
+                and (
+                    spec.version is None
+                    or spec.version > policy_versions[spec.name].version
+                )
             )
             for spec in specs
         )

From 5883e35c07ca10ee22e15bc26f97484ff3de0627 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Sun, 30 Nov 2025 15:58:39 +0100
Subject: [PATCH 12/57] gracefully handle unpinned but not ignored dependencies

---
 minimum_versions/formatting.py | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/minimum_versions/formatting.py b/minimum_versions/formatting.py
index 7c9c879..a6f47da 100644
--- a/minimum_versions/formatting.py
+++ b/minimum_versions/formatting.py
@@ -21,7 +21,9 @@ def lookup_spec_release(spec, releases):
 
 
 def version_comparison_symbol(required, policy):
-    if required < policy:
+    if required is None:
+        return "!"
+    elif required < policy:
         return "<"
     elif required > policy:
         return ">"
@@ -45,6 +47,7 @@ def format_bump_table(specs, policy_versions, releases, warnings, ignored_violat
         ">": Style(color="#ff0000", bold=True),
         "=": Style(color="#008700", bold=True),
         "<": Style(color="#d78700", bold=True),
+        "!": Style(color="#ff0000", bold=True),
     }
 
     for spec in specs:
@@ -53,7 +56,13 @@ def format_bump_table(specs, policy_versions, releases, warnings, ignored_violat
         policy_date = policy_release.timestamp
 
         required_version = spec.version
-        required_date = lookup_spec_release(spec, releases).timestamp
+        if required_version is None:
+            warnings[spec.name].append(
+                "Unpinned dependency. Consider pinning or ignoring this dependency."
+            )
+            required_date = None
+        else:
+            required_date = lookup_spec_release(spec, releases).timestamp
 
         status = version_comparison_symbol(required_version, policy_version)
         if status == ">" and spec.name in ignored_violations:
@@ -63,8 +72,8 @@ def format_bump_table(specs, policy_versions, releases, warnings, ignored_violat
 
         table.add_row(
             spec.name,
-            str(required_version),
-            f"{required_date:%Y-%m-%d}",
+            str(required_version) if required_version is not None else "",
+            f"{required_date:%Y-%m-%d}" if required_date is not None else "",
             str(policy_version),
             f"{policy_date:%Y-%m-%d}",
             status,

From 0bb207d34727e90a693326056dc5e4a6fb889482 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Sun, 30 Nov 2025 16:09:02 +0100
Subject: [PATCH 13/57] install the module instead of modifying `sys.path`

---
 action.yaml | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/action.yaml b/action.yaml
index 82a9fdc..4deddc3 100644
--- a/action.yaml
+++ b/action.yaml
@@ -28,6 +28,7 @@ runs:
       run: |
         echo "::group::Install dependencies"
         python -m pip install -r ${{ github.action_path }}/requirements.txt
+        python -m pip install ${{ github.action_path }}
         echo "::endgroup::"
     - name: analyze environments
       shell: bash -l {0}
@@ -38,4 +39,7 @@ runs:
         ENVIRONMENT_PATHS: ${{ inputs.environment-paths }}
         TODAY: ${{ inputs.today }}
       run: |
-        PYTHONPATH=${{github.action_path}} python -m minimum_versions validate --today="$TODAY" --policy="$POLICY_PATH" $ENVIRONMENT_PATHS
+        python -m minimum_versions validate \
+          --today="$TODAY" \
+          --policy="$POLICY_PATH" \
+          $ENVIRONMENT_PATHS

From 6795a27caf00cd1485068eab6d0c4efdc4cca780 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Sun, 30 Nov 2025 16:27:10 +0100
Subject: [PATCH 14/57] allow passing `manifest-path` to the action

---
 action.yaml              |  8 +++++++-
 minimum_versions/main.py | 13 ++++++++++++-
 2 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/action.yaml b/action.yaml
index 4deddc3..8683eb7 100644
--- a/action.yaml
+++ b/action.yaml
@@ -17,8 +17,12 @@ inputs:
       Time machine for testing
     required: false
     type: string
+  manifest-path: >-
+    description: >-
+      Path to the manifest file of `pixi`. Required for `pixi` environments.
+    required: false
+    type: string
 outputs: {}
-
 runs:
   using: "composite"
 
@@ -38,8 +42,10 @@ runs:
         POLICY_PATH: ${{ inputs.policy }}
         ENVIRONMENT_PATHS: ${{ inputs.environment-paths }}
         TODAY: ${{ inputs.today }}
+        MANIFEST_PATH: ${{ inputs.manifest-path }}
       run: |
         python -m minimum_versions validate \
           --today="$TODAY" \
           --policy="$POLICY_PATH" \
+          --manifest-path="$MANIFEST_PATH" \
           $ENVIRONMENT_PATHS
diff --git a/minimum_versions/main.py b/minimum_versions/main.py
index 29cda01..4857c2a 100644
--- a/minimum_versions/main.py
+++ b/minimum_versions/main.py
@@ -2,6 +2,7 @@
 import os.path
 import pathlib
 import sys
+from typing import Any
 
 import rich_click as click
 from rich.console import Console
@@ -24,6 +25,16 @@ def parse_date(string):
     return datetime.datetime.strptime(string, "%Y-%m-%d").date()
 
 
+class _Path(click.Path):
+    def convert(
+        self, value: Any, param: click.Parameter | None, ctx: click.Context | None
+    ) -> Any:
+        if not value:
+            return None
+
+        return super().convert(value, param, ctx)
+
+
 @click.group()
 def main():
     pass
@@ -34,7 +45,7 @@ def main():
 @click.option(
     "--manifest-path",
     "manifest_path",
-    type=click.Path(exists=True, path_type=pathlib.Path),
+    type=_Path(exists=True, path_type=pathlib.Path),
     default=None,
 )
 @click.option("--today", type=parse_date, default=None)

From 851d0a6eacbdc0dc1bae069427862f0d2012ee46 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Sun, 30 Nov 2025 16:37:57 +0100
Subject: [PATCH 15/57] misformatted input definition

---
 action.yaml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/action.yaml b/action.yaml
index 8683eb7..a59cb67 100644
--- a/action.yaml
+++ b/action.yaml
@@ -17,7 +17,7 @@ inputs:
       Time machine for testing
     required: false
     type: string
-  manifest-path: >-
+  manifest-path:
     description: >-
       Path to the manifest file of `pixi`. Required for `pixi` environments.
     required: false

From 0144607d51e6d3792a4d05661f0e6f4921498822 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Sun, 30 Nov 2025 16:39:33 +0100
Subject: [PATCH 16/57] stop testing on the unsupported python 3.10

---
 .github/workflows/ci.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 0be3c0f..abd54e2 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -16,7 +16,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.10", "3.11", "3.12", "3.13"]
+        python-version: ["3.11", "3.12", "3.13"]
 
     steps:
       - name: clone the repository

From 741a436f02ef597c80814cf0e7660ee1dcb269cf Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Sun, 30 Nov 2025 16:39:47 +0100
Subject: [PATCH 17/57] install the package itself

---
 .github/workflows/ci.yml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index abd54e2..2af15ba 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -31,6 +31,7 @@ jobs:
       - name: install dependencies
         run: |
           python -m pip install -r requirements.txt
+          python -m pip install .
           python -m pip install pytest
       - name: run tests
         run: |

From f56c537da235ad302512d24703784706eb75823b Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Sun, 30 Nov 2025 22:14:40 +0100
Subject: [PATCH 18/57] use the warning style for unpinned versions

---
 minimum_versions/formatting.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/minimum_versions/formatting.py b/minimum_versions/formatting.py
index a6f47da..ba6fca9 100644
--- a/minimum_versions/formatting.py
+++ b/minimum_versions/formatting.py
@@ -47,7 +47,7 @@ def format_bump_table(specs, policy_versions, releases, warnings, ignored_violat
         ">": Style(color="#ff0000", bold=True),
         "=": Style(color="#008700", bold=True),
         "<": Style(color="#d78700", bold=True),
-        "!": Style(color="#ff0000", bold=True),
+        "!": warning_style,
     }
 
     for spec in specs:

From afd85b45cadac14d6c4ac7d8897f4f15e1dc702c Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Sun, 30 Nov 2025 22:32:37 +0100
Subject: [PATCH 19/57] warn about ignored PyPI dependencies

---
 minimum_versions/environments/pixi.py | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/minimum_versions/environments/pixi.py b/minimum_versions/environments/pixi.py
index b3ec25f..48a00c6 100644
--- a/minimum_versions/environments/pixi.py
+++ b/minimum_versions/environments/pixi.py
@@ -93,6 +93,16 @@ def parse_pixi_environment(name: str, manifest_path: pathlib.Path | None):
 
     specs = []
     warnings = []
+
+    pypi_dependencies = {
+        feature: get_in([feature, "pypi-dependencies"], all_features, default=[])
+        for feature in env["features"]
+    }
+    with_pypi_dependencies = {
+        feature: bool(deps) for feature, deps in pypi_dependencies.items() if deps
+    }
+    for feature in with_pypi_dependencies:
+        warnings.append((f"feature:{feature}", ["Ignored PyPI dependencies."]))
     for name, pin in pins.items():
         spec, warnings_ = parse_spec(name, pin)
 

From 51da18a663b9939c4d44e9f8f1be139aecece4b1 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Tue, 2 Dec 2025 20:47:15 +0100
Subject: [PATCH 20/57] tests for most of the functions in
 `minimum_versions.release`

---
 minimum_versions/tests/test_release.py | 112 +++++++++++++++++++++++++
 1 file changed, 112 insertions(+)
 create mode 100644 minimum_versions/tests/test_release.py

diff --git a/minimum_versions/tests/test_release.py b/minimum_versions/tests/test_release.py
new file mode 100644
index 0000000..875a59e
--- /dev/null
+++ b/minimum_versions/tests/test_release.py
@@ -0,0 +1,112 @@
+import datetime as dt
+from dataclasses import dataclass
+
+import pytest
+from rattler import PackageName, Version
+
+from minimum_versions import release
+
+
+@dataclass
+class FakePackageRecord:
+    name: PackageName
+    version: Version
+    build_number: int
+    timestamp: dt.datetime
+
+
+@pytest.fixture
+def timestamps():
+    yield [
+        dt.datetime(2025, 12, 2, 20, 24, 40),
+        dt.datetime(2025, 12, 2, 20, 25, 40),
+        dt.datetime(2025, 12, 2, 20, 20, 40),
+    ]
+
+
+@pytest.fixture
+def records(timestamps):
+    yield [
+        FakePackageRecord(
+            name=PackageName("test1"),
+            version=Version("1.0.0"),
+            build_number=1,
+            timestamp=timestamps[0],
+        ),
+        FakePackageRecord(
+            name=PackageName("test1"),
+            version=Version("1.0.1"),
+            build_number=0,
+            timestamp=None,
+        ),
+        FakePackageRecord(
+            name=PackageName("test2"),
+            version=Version("1.0.0"),
+            build_number=0,
+            timestamp=timestamps[2],
+        ),
+    ]
+
+
+@pytest.fixture
+def releases(timestamps):
+    yield {
+        "test1": [
+            release.Release(
+                version=Version("1.0.0"), build_number=1, timestamp=timestamps[0]
+            ),
+            release.Release(version=Version("1.0.1"), build_number=0, timestamp=None),
+        ],
+        "test2": [
+            release.Release(
+                version=Version("1.0.0"), build_number=0, timestamp=timestamps[2]
+            )
+        ],
+    }
+
+
+def test_release_from_repodata_record():
+    repo_data = FakePackageRecord(
+        name=PackageName("test"),
+        version=Version("1.0.1"),
+        build_number=0,
+        timestamp=dt.datetime(2025, 12, 2, 20, 24, 40),
+    )
+
+    actual = release.Release.from_repodata_record(repo_data)
+
+    assert actual.version == repo_data.version
+    assert actual.build_number == repo_data.build_number
+    assert actual.timestamp == repo_data.timestamp
+
+
+def test_group_packages(records, releases):
+    actual = release.group_packages(records)
+    expected = releases
+
+    assert actual == expected
+
+
+@pytest.mark.parametrize(
+    ["predicate", "expected"],
+    (
+        (
+            lambda r: r.timestamp is None,
+            {"test1": [release.Release(Version("1.0.1"), 0, None)], "test2": []},
+        ),
+        (
+            lambda r: r.build_number == 1,
+            {
+                "test1": [
+                    release.Release(
+                        Version("1.0.0"), 1, dt.datetime(2025, 12, 2, 20, 24, 40)
+                    )
+                ],
+                "test2": [],
+            },
+        ),
+    ),
+)
+def test_filter_releases(releases, predicate, expected):
+    actual = release.filter_releases(predicate, releases)
+    assert actual == expected

From c53cf3314e3db4dab697562c1e5075456bd7b10e Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Mon, 8 Dec 2025 21:16:49 +0100
Subject: [PATCH 21/57] tests for the environment functions

---
 minimum_versions/tests/test_environments.py | 82 +++++++++++++++++++++
 1 file changed, 82 insertions(+)
 create mode 100644 minimum_versions/tests/test_environments.py

diff --git a/minimum_versions/tests/test_environments.py b/minimum_versions/tests/test_environments.py
new file mode 100644
index 0000000..c83f5fb
--- /dev/null
+++ b/minimum_versions/tests/test_environments.py
@@ -0,0 +1,82 @@
+from dataclasses import dataclass
+
+import pytest
+from rattler import Version
+
+from minimum_versions import environments
+from minimum_versions.environments.spec import Spec
+
+
+@dataclass
+class FakeRecord:
+    version: Version | None
+
+
+@pytest.mark.parametrize("manifest_path", ("a/pixi.toml", "b/pyproject.toml", None))
+@pytest.mark.parametrize(
+    ["specifier", "key"], (("conda:ci/environment.yml", "conda"), ("pixi:env", "pixi"))
+)
+def test_parse_environment(specifier, manifest_path, key, monkeypatch):
+    results = {"conda": object(), "pixi": object()}
+    kinds = {
+        "conda": lambda s, m: results["conda"],
+        "pixi": lambda s, m: results["pixi"],
+    }
+    monkeypatch.setattr(environments, "kinds", kinds)
+
+    actual = environments.parse_environment(specifier, manifest_path)
+    expected = results[key]
+
+    assert actual is expected
+
+
+@pytest.mark.parametrize(
+    ["envs", "ignored_violations", "expected"],
+    (
+        pytest.param(
+            {
+                "env1": [
+                    Spec("a", Version("1.2")),
+                    Spec("c", Version("2024.8")),
+                    Spec("d", Version("0.6")),
+                ]
+            },
+            ["d"],
+            {"env1": False},
+            id="single-violation-ignored",
+        ),
+        pytest.param(
+            {
+                "env1": [Spec("b", Version("3.2")), Spec("c", Version("2025.2"))],
+                "env2": [Spec("b", Version("3.1"))],
+            },
+            [],
+            {"env1": True, "env2": False},
+            id="multiple-split-not ignored",
+        ),
+        pytest.param(
+            {"env1": [Spec("d", None)]},
+            [],
+            {"env1": True},
+            id="single-none-not ignored",
+        ),
+        pytest.param(
+            {"env1": [Spec("d", None)]},
+            ["d"],
+            {"env1": False},
+            id="single-none-ignored",
+        ),
+    ),
+)
+def test_compare_versions(envs, ignored_violations, expected):
+    policy_versions = {
+        "a": FakeRecord(version=Version("1.2")),
+        "b": FakeRecord(version=Version("3.1")),
+        "c": FakeRecord(version=Version("2025.1")),
+        "d": FakeRecord(version=Version("0.5")),
+    }
+
+    actual = environments.spec.compare_versions(
+        envs, policy_versions, ignored_violations
+    )
+    assert actual == expected

From 36019e333aeaaee51877d9a0390689f741b07d21 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Mon, 8 Dec 2025 21:29:58 +0100
Subject: [PATCH 22/57] tests for parsing conda specs

---
 minimum_versions/tests/test_environments.py | 66 +++++++++++++++++++++
 1 file changed, 66 insertions(+)

diff --git a/minimum_versions/tests/test_environments.py b/minimum_versions/tests/test_environments.py
index c83f5fb..b53d744 100644
--- a/minimum_versions/tests/test_environments.py
+++ b/minimum_versions/tests/test_environments.py
@@ -80,3 +80,69 @@ def test_compare_versions(envs, ignored_violations, expected):
         envs, policy_versions, ignored_violations
     )
     assert actual == expected
+
+
+class TestParseCondaEnvironment:
+    @pytest.mark.parametrize(
+        ["spec_text", "expected_spec", "expected_warnings"],
+        (
+            pytest.param(
+                "a=3.2", Spec("a", Version("3.2")), [], id="exact-no_warnings"
+            ),
+            pytest.param(
+                "b>=1.1",
+                Spec("b", Version("1.1")),
+                [
+                    "package must be pinned with an exact version: 'b>=1.1'."
+                    " Using the version as an exact pin instead."
+                ],
+                id="lower_bound",
+            ),
+            pytest.param(
+                "b<=4.1",
+                Spec("b", Version("4.1")),
+                [
+                    "package must be pinned with an exact version: 'b<=4.1'."
+                    " Using the version as an exact pin instead."
+                ],
+                id="upper_equal_bound",
+            ),
+            pytest.param(
+                "b<4.1",
+                Spec("b", Version("4.1")),
+                [
+                    "package must be pinned with an exact version: 'b<=4.1'."
+                    " Using the version as an exact pin instead."
+                ],
+                marks=pytest.mark.xfail(
+                    reason="exclusive upper bounds are not supported"
+                ),
+                id="upper_bound",
+            ),
+            pytest.param(
+                "b>4.1",
+                Spec("b", Version("4.1")),
+                [
+                    "package must be pinned with an exact version: 'b>4.1'."
+                    " Using the version as an exact pin instead."
+                ],
+                marks=pytest.mark.xfail(
+                    reason="exclusive lower bounds are not supported"
+                ),
+                id="lower_bound",
+            ),
+            pytest.param(
+                "c=1.6.2",
+                Spec("c", Version("1.6.2")),
+                ["package should be pinned to a minor version (got 1.6.2)"],
+            ),
+        ),
+    )
+    def test_parse_spec(self, spec_text, expected_spec, expected_warnings):
+        actual_spec, (actual_name, actual_warnings) = environments.conda.parse_spec(
+            spec_text
+        )
+
+        assert actual_spec == expected_spec
+        assert actual_name == expected_spec.name
+        assert actual_warnings == expected_warnings

From a1c08cff99630a6e9ce62d56932dea0ae8943671 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Mon, 8 Dec 2025 21:53:55 +0100
Subject: [PATCH 23/57] also check parsing the entire conda env

---
 minimum_versions/tests/test_environments.py | 39 +++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/minimum_versions/tests/test_environments.py b/minimum_versions/tests/test_environments.py
index b53d744..7e7adfe 100644
--- a/minimum_versions/tests/test_environments.py
+++ b/minimum_versions/tests/test_environments.py
@@ -1,3 +1,5 @@
+import pathlib
+import textwrap
 from dataclasses import dataclass
 
 import pytest
@@ -146,3 +148,40 @@ def test_parse_spec(self, spec_text, expected_spec, expected_warnings):
         assert actual_spec == expected_spec
         assert actual_name == expected_spec.name
         assert actual_warnings == expected_warnings
+
+    def test_parse_environment(self, monkeypatch):
+        data = textwrap.dedent(
+            """\
+            channels:
+            - conda-forge
+            dependencies:
+            - a=1.1
+            - b>=3.2
+            - c=1.6.5
+            """.rstrip()
+        )
+        monkeypatch.setattr(pathlib.Path, "read_text", lambda _: data)
+
+        expected_specs = [
+            Spec("a", Version("1.1")),
+            Spec("b", Version("3.2")),
+            Spec("c", Version("1.6.5")),
+        ]
+        expected_warnings = [
+            ("a", []),
+            (
+                "b",
+                [
+                    "package must be pinned with an exact version: 'b>=3.2'."
+                    " Using the version as an exact pin instead."
+                ],
+            ),
+            ("c", ["package should be pinned to a minor version (got 1.6.5)"]),
+        ]
+
+        actual_specs, actual_warnings = environments.conda.parse_conda_environment(
+            "env1.yaml", None
+        )
+
+        assert actual_specs == expected_specs
+        assert actual_warnings == expected_warnings

From 8f0fa55cec9c53f1cb8676ebca6c8927a94cfde4 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Mon, 8 Dec 2025 22:01:55 +0100
Subject: [PATCH 24/57] rename

---
 minimum_versions/tests/test_environments.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/minimum_versions/tests/test_environments.py b/minimum_versions/tests/test_environments.py
index 7e7adfe..ff8dcf3 100644
--- a/minimum_versions/tests/test_environments.py
+++ b/minimum_versions/tests/test_environments.py
@@ -84,7 +84,7 @@ def test_compare_versions(envs, ignored_violations, expected):
     assert actual == expected
 
 
-class TestParseCondaEnvironment:
+class TestCondaEnvironment:
     @pytest.mark.parametrize(
         ["spec_text", "expected_spec", "expected_warnings"],
         (

From b979674aa5c41549788000646d82a584841b8aa3 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Mon, 8 Dec 2025 22:06:32 +0100
Subject: [PATCH 25/57] check parsing pixi specs

---
 minimum_versions/tests/test_environments.py | 40 +++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/minimum_versions/tests/test_environments.py b/minimum_versions/tests/test_environments.py
index ff8dcf3..f60b4d2 100644
--- a/minimum_versions/tests/test_environments.py
+++ b/minimum_versions/tests/test_environments.py
@@ -185,3 +185,43 @@ def test_parse_environment(self, monkeypatch):
 
         assert actual_specs == expected_specs
         assert actual_warnings == expected_warnings
+
+
+class TestPixiEnvironment:
+    @pytest.mark.parametrize(
+        ["name", "version_text", "expected_spec", "expected_warnings"],
+        (
+            pytest.param(
+                "a", "1.2.*", Spec("a", Version("1.2")), [], id="star_pin–no_warnings"
+            ),
+            pytest.param(
+                "b",
+                ">=3.1",
+                Spec("b", Version("3.1")),
+                [
+                    "package must be pinned with an exact version: '>=3.1'."
+                    " Using the version as an exact pin instead."
+                ],
+                id="lower_pin",
+            ),
+            pytest.param(
+                "c",
+                ">=1.6.0,<1.7.0",
+                Spec("c", Version("1.6")),
+                [
+                    "lower pin '1.6.0' and upper pin '1.7.0' found."
+                    " Using the lower pin for now, please convert to"
+                    " the standard x.y.* syntax."
+                ],
+                id="tight_pin",
+            ),
+        ),
+    )
+    def test_parse_spec(self, name, version_text, expected_spec, expected_warnings):
+        actual_spec, (actual_name, actual_warnings) = environments.pixi.parse_spec(
+            name, version_text
+        )
+
+        assert actual_spec == expected_spec
+        assert actual_name == name
+        assert actual_warnings == expected_warnings

From 878aa35c4c2e1afc2fa524edc388520bee5d6295 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Mon, 8 Dec 2025 22:06:45 +0100
Subject: [PATCH 26/57] fix a bug in the lower pin regex

---
 minimum_versions/environments/pixi.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/minimum_versions/environments/pixi.py b/minimum_versions/environments/pixi.py
index 48a00c6..d520616 100644
--- a/minimum_versions/environments/pixi.py
+++ b/minimum_versions/environments/pixi.py
@@ -7,7 +7,7 @@
 
 from minimum_versions.environments.spec import Spec
 
-_version_re = r"[0-9]+\.[0-9]+(?:\.[0-9]+|\.\*)"
+_version_re = r"[0-9]+\.[0-9]+(?:\.[0-9]+|\.\*)?"
 version_re = re.compile(f"(?P<version>{_version_re})")
 lower_pin_re = re.compile(rf">=(?P<version>{_version_re})$")
 tight_pin_re = re.compile(rf">=(?P<lower>{_version_re}),<(?P<upper>{_version_re})")

From 9cfadc7ebbc3bbbd46e7adb9aa1df8df9b4ec68d Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Mon, 8 Dec 2025 22:10:25 +0100
Subject: [PATCH 27/57] additional spec parsing checks

---
 minimum_versions/tests/test_environments.py | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/minimum_versions/tests/test_environments.py b/minimum_versions/tests/test_environments.py
index f60b4d2..9dcd12c 100644
--- a/minimum_versions/tests/test_environments.py
+++ b/minimum_versions/tests/test_environments.py
@@ -215,6 +215,14 @@ class TestPixiEnvironment:
                 ],
                 id="tight_pin",
             ),
+            pytest.param(
+                "d",
+                "1.9.1",
+                Spec("d", Version("1.9.1")),
+                ["package should be pinned to a minor version (got 1.9.1)"],
+                id="patch_pin",
+            ),
+            pytest.param("e", "*", Spec("e", None), [], id="unpinned"),
         ),
     )
     def test_parse_spec(self, name, version_text, expected_spec, expected_warnings):

From 7f9863b7a7ee42537104e77825acb8d84e905333 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Mon, 8 Dec 2025 22:14:01 +0100
Subject: [PATCH 28/57] check invalid versions raise

---
 minimum_versions/tests/test_environments.py | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/minimum_versions/tests/test_environments.py b/minimum_versions/tests/test_environments.py
index 9dcd12c..1ea2362 100644
--- a/minimum_versions/tests/test_environments.py
+++ b/minimum_versions/tests/test_environments.py
@@ -233,3 +233,8 @@ def test_parse_spec(self, name, version_text, expected_spec, expected_warnings):
         assert actual_spec == expected_spec
         assert actual_name == name
         assert actual_warnings == expected_warnings
+
+    @pytest.mark.parametrize("version_text", ("~1.3", "^2.1", "<1.1"))
+    def test_parse_spec_error(self, version_text):
+        with pytest.raises(ValueError, match="Unknown version format: .*"):
+            environments.pixi.parse_spec("package", version_text)

From c7c1179f490238bfeab76ceca50444676e31dbc3 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Mon, 8 Dec 2025 22:25:26 +0100
Subject: [PATCH 29/57] checks for parse_pixi_environment

---
 minimum_versions/tests/test_environments.py | 34 +++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/minimum_versions/tests/test_environments.py b/minimum_versions/tests/test_environments.py
index 1ea2362..b315a7d 100644
--- a/minimum_versions/tests/test_environments.py
+++ b/minimum_versions/tests/test_environments.py
@@ -1,3 +1,4 @@
+import io
 import pathlib
 import textwrap
 from dataclasses import dataclass
@@ -238,3 +239,36 @@ def test_parse_spec(self, name, version_text, expected_spec, expected_warnings):
     def test_parse_spec_error(self, version_text):
         with pytest.raises(ValueError, match="Unknown version format: .*"):
             environments.pixi.parse_spec("package", version_text)
+
+    def test_parse_pixi_environment(self, monkeypatch):
+        data = textwrap.dedent(
+            """\
+            [dependencies]
+            a = "1.0.*"
+            b = "2.2.*"
+
+            [feature.feature1.dependencies]
+            c = "3.1.*"
+
+            [environments]
+            env1 = { features = ["feature1"] }
+            """.rstrip()
+        )
+        monkeypatch.setattr(
+            pathlib.Path, "open", lambda _, mode: io.BytesIO(data.encode())
+        )
+
+        name = "env1"
+        manifest_path = pathlib.Path("pixi.toml")
+
+        actual_specs, actual_warnings = environments.pixi.parse_pixi_environment(
+            name, manifest_path
+        )
+        expected_specs = [
+            Spec("a", Version("1.0")),
+            Spec("b", Version("2.2")),
+            Spec("c", Version("3.1")),
+        ]
+        expected_warnings = [("a", []), ("b", []), ("c", [])]
+        assert actual_specs == expected_specs
+        assert actual_warnings == expected_warnings

From c2351bf1a0af361607a3010a798f44d97f588829 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Mon, 8 Dec 2025 22:25:44 +0100
Subject: [PATCH 30/57] include the default feature in the features

---
 minimum_versions/environments/pixi.py | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/minimum_versions/environments/pixi.py b/minimum_versions/environments/pixi.py
index d520616..1426842 100644
--- a/minimum_versions/environments/pixi.py
+++ b/minimum_versions/environments/pixi.py
@@ -85,8 +85,15 @@ def parse_pixi_environment(name: str, manifest_path: pathlib.Path | None):
     if env is None:
         raise ValueError(f"Unknown environment: {name}")
 
-    features = [
-        get_in([feature, "dependencies"], all_features) for feature in env["features"]
+    if isinstance(env, list):
+        feature_names = env
+    elif isinstance(env, dict) and list(env) != ["features"]:
+        raise ValueError("Options other than 'features' are not supported.")
+    else:
+        feature_names = env["features"]
+
+    features = [pixi_config.get("dependencies", [])] + [
+        get_in([feature, "dependencies"], all_features) for feature in feature_names
     ]
 
     pins = merge(features)

From abf286ff72cfeb58414433e0c03cd3fd2b54da6f Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Mon, 8 Dec 2025 22:41:15 +0100
Subject: [PATCH 31/57] rename the `environment-paths` input to `environments`

---
 action.yaml | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/action.yaml b/action.yaml
index a59cb67..00ca955 100644
--- a/action.yaml
+++ b/action.yaml
@@ -7,16 +7,18 @@ inputs:
       The path to the policy to follow
     required: true
     type: string
-  environment-paths:
-    description: >-
-      The paths to the environment files
-    required: true
-    type: list
   today:
     description: >-
       Time machine for testing
     required: false
     type: string
+  environments:
+    description: >-
+      The names or paths of the environments. Pixi environment names must be
+      prefixed with `pixi:`. Conda environment paths may be prefixed with
+      `conda:`. If there is no prefix, it is assumed to be a conda env path.
+    required: true
+    type: list
   manifest-path:
     description: >-
       Path to the manifest file of `pixi`. Required for `pixi` environments.
@@ -40,7 +42,7 @@ runs:
         COLUMNS: 120
         FORCE_COLOR: 3
         POLICY_PATH: ${{ inputs.policy }}
-        ENVIRONMENT_PATHS: ${{ inputs.environment-paths }}
+        ENVIRONMENTS: ${{ inputs.environment }}
         TODAY: ${{ inputs.today }}
         MANIFEST_PATH: ${{ inputs.manifest-path }}
       run: |
@@ -48,4 +50,4 @@ runs:
           --today="$TODAY" \
           --policy="$POLICY_PATH" \
           --manifest-path="$MANIFEST_PATH" \
-          $ENVIRONMENT_PATHS
+          $ENVIRONMENTS

From 8473575f34412c9dda64fec2770fb29a70d39e93 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Mon, 8 Dec 2025 22:41:51 +0100
Subject: [PATCH 32/57] describe how to analyze `pixi` environments

---
 README.md | 65 +++++++++++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 61 insertions(+), 4 deletions(-)

diff --git a/README.md b/README.md
index 62b3fba..a11fa60 100644
--- a/README.md
+++ b/README.md
@@ -42,7 +42,11 @@ them to an empty mapping or sequence, respectively:
   ignored_violations: []
 ```
 
-Then add a new step to CI:
+Then add a new step to CI.
+
+### conda
+
+To analyze conda environments, simply pass the path to the environment file (`env.yaml`) to the `environments` key.
 
 ```yaml
 jobs:
@@ -53,7 +57,7 @@ jobs:
     - uses: xarray-contrib/minimum-dependency-versions@version
       with:
         policy: policy.yaml
-        environment-paths: path/to/env.yaml
+        environments: path/to/env.yaml
 ```
 
 To analyze multiple environments at the same time, pass a multi-line string:
@@ -67,8 +71,61 @@ jobs:
 
     - uses: xarray-contrib/minimum-dependency-versions@version
       with:
-        environment-paths: |
+        environments: |
           path/to/env1.yaml
           path/to/env2.yaml
-          path/to/env3.yaml
+          conda:path/to/env3.yaml  # the conda: prefix is optional
+```
+
+### pixi
+
+To analyze pixi environments, specify the environment name prefixed with `pixi:` and point to the manifest file using `manifest-path`:
+
+```yaml
+jobs:
+  my-job:
+    ...
+    steps:
+    ...
+
+    - uses: xarray-contrib/minimum-dependency-versions@version
+      with:
+        environments: pixi:env1
+        manifest-path: /path/to/pixi.toml  # or pyproject.toml
+```
+
+Multiple environments can be analyzed at the same time:
+
+```yaml
+jobs:
+  my-job:
+    ...
+    steps:
+    ...
+
+    - uses: xarray-contrib/minimum-dependency-versions@version
+      with:
+        environments: |
+          pixi:env1
+          pixi:env2
+        manifest-path: /path/to/pixi.toml  # or pyproject.toml
+```
+
+### Mixing environment types
+
+It is even possible to mix environment types (once again, the `conda:` prefix is optional but recommended):
+
+```yaml
+jobs:
+  my-job:
+    ...
+    steps:
+    ...
+
+    - uses: xarray-contrib/minimum-dependency-versions@version
+      with:
+        environments: |
+          pixi:env1
+          conda:path/to/env.yaml
+        manifest-path: path/to/pixi.toml  # or pyproject.toml
 ```

From 2ed43755b19990b5ad0da485ddd3420251e7ab59 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Mon, 8 Dec 2025 22:47:59 +0100
Subject: [PATCH 33/57] rename `env-paths` to `envs`

---
 .github/workflows/ci.yml | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 2af15ba..1ea8acc 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -44,7 +44,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        env-paths:
+        envs:
           - "envs/env1.yaml"
           - "envs/env2.yaml"
           - |
@@ -53,16 +53,16 @@ jobs:
         expected-failure: ["false"]
         policy-file: ["policy.yaml"]
         include:
-          - env-paths: |
+          - envs: |
               envs/failing-env1.yaml
             policy-file: "policy.yaml"
             expected-failure: "true"
-          - env-paths: |
+          - envs: |
               envs/env1.yaml
               envs/failing-env1.yaml
             policy-file: "policy.yaml"
             expected-failure: "true"
-          - env-paths: "envs/env1.yaml"
+          - envs: "envs/env1.yaml"
             policy-file: policy_no_extra_options.yaml
             expected-failure: "false"
 
@@ -75,8 +75,9 @@ jobs:
         continue-on-error: true
         with:
           policy: ${{ matrix.policy-file }}
-          environment-paths: ${{ matrix.env-paths }}
+          environments: ${{ matrix.envs }}
           today: 2024-12-20
+          manifest-path: ${{ matrix.manifest-paths }}
       - name: detect outcome
         if: always()
         shell: bash -l {0}

From 81c9530c00e47068c6270e9b0b2041e393f80820 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Mon, 8 Dec 2025 22:50:47 +0100
Subject: [PATCH 34/57] e2e tests for pixi and mixed envs

---
 .github/workflows/ci.yml | 10 ++++++++++
 envs/pixi.toml           | 14 ++++++++++++++
 2 files changed, 24 insertions(+)
 create mode 100644 envs/pixi.toml

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 1ea8acc..b2bdba1 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -65,6 +65,16 @@ jobs:
           - envs: "envs/env1.yaml"
             policy-file: policy_no_extra_options.yaml
             expected-failure: "false"
+          - envs: pixi:env1
+            manifest-path: envs/pixi.toml
+          - envs: |
+              pixi:env1
+              pixi:env2
+            manifest-path: envs/pixi.toml
+          - envs: |
+              pixi:env1
+              conda:envs/env2.yaml
+            manifest-path: envs/pixi.toml
 
     steps:
       - name: clone the repository
diff --git a/envs/pixi.toml b/envs/pixi.toml
new file mode 100644
index 0000000..06a5ffd
--- /dev/null
+++ b/envs/pixi.toml
@@ -0,0 +1,14 @@
+[dependencies]
+numpy = "1.24"
+pandas = "2.1"
+packaging = "23.1"
+
+[feature.py310.dependencies]
+python = "3.10"
+
+[feature.py311.dependencies]
+python = "3.11"
+
+[environments]
+env1 = { features = ["py310"] }
+env2 = ["py311"]

From cc8ee846e05705779c42c73552ccbc68372ff73b Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Mon, 8 Dec 2025 22:52:24 +0100
Subject: [PATCH 35/57] typo

---
 action.yaml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/action.yaml b/action.yaml
index 00ca955..cf3e5bf 100644
--- a/action.yaml
+++ b/action.yaml
@@ -42,7 +42,7 @@ runs:
         COLUMNS: 120
         FORCE_COLOR: 3
         POLICY_PATH: ${{ inputs.policy }}
-        ENVIRONMENTS: ${{ inputs.environment }}
+        ENVIRONMENTS: ${{ inputs.environments }}
         TODAY: ${{ inputs.today }}
         MANIFEST_PATH: ${{ inputs.manifest-path }}
       run: |

From 3f55bc2805573c8bf62ecd47282524a522a732eb Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Mon, 8 Dec 2025 22:53:40 +0100
Subject: [PATCH 36/57] add policy files for the pixi tests

---
 .github/workflows/ci.yml | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index b2bdba1..c290dc0 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -67,14 +67,17 @@ jobs:
             expected-failure: "false"
           - envs: pixi:env1
             manifest-path: envs/pixi.toml
+            policy-file: "policy.yaml"
           - envs: |
               pixi:env1
               pixi:env2
             manifest-path: envs/pixi.toml
+            policy-file: "policy.yaml"
           - envs: |
               pixi:env1
               conda:envs/env2.yaml
             manifest-path: envs/pixi.toml
+            policy-file: "policy.yaml"
 
     steps:
       - name: clone the repository

From a5ac0082157ef9ef4c9f2c0bf62895a1dea4b097 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Mon, 8 Dec 2025 22:55:39 +0100
Subject: [PATCH 37/57] another typo

---
 .github/workflows/ci.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index c290dc0..ba80b4e 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -90,7 +90,7 @@ jobs:
           policy: ${{ matrix.policy-file }}
           environments: ${{ matrix.envs }}
           today: 2024-12-20
-          manifest-path: ${{ matrix.manifest-paths }}
+          manifest-path: ${{ matrix.manifest-path }}
       - name: detect outcome
         if: always()
         shell: bash -l {0}

From 9d266d93d60b696d4590ef172433e5390b5cef91 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Mon, 8 Dec 2025 22:59:05 +0100
Subject: [PATCH 38/57] quotes and expected failure settings

---
 .github/workflows/ci.yml | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index ba80b4e..75d4920 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -63,21 +63,24 @@ jobs:
             policy-file: "policy.yaml"
             expected-failure: "true"
           - envs: "envs/env1.yaml"
-            policy-file: policy_no_extra_options.yaml
+            policy-file: "policy_no_extra_options.yaml"
             expected-failure: "false"
-          - envs: pixi:env1
-            manifest-path: envs/pixi.toml
+          - envs: "pixi:env1"
+            manifest-path: "envs/pixi.toml"
             policy-file: "policy.yaml"
+            expected-failure: "false"
           - envs: |
               pixi:env1
               pixi:env2
-            manifest-path: envs/pixi.toml
+            manifest-path: "envs/pixi.toml"
             policy-file: "policy.yaml"
+            expected-failure: "false"
           - envs: |
               pixi:env1
               conda:envs/env2.yaml
-            manifest-path: envs/pixi.toml
+            manifest-path: "envs/pixi.toml"
             policy-file: "policy.yaml"
+            expected-failure: "false"
 
     steps:
       - name: clone the repository

From 0d5add7efbd41aaff03f2b26a33f144ec58894ff Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Mon, 8 Dec 2025 22:59:16 +0100
Subject: [PATCH 39/57] add a failing pixi env

---
 .github/workflows/ci.yml | 4 ++++
 envs/pixi.toml           | 6 +++++-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 75d4920..42a5162 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -81,6 +81,10 @@ jobs:
             manifest-path: "envs/pixi.toml"
             policy-file: "policy.yaml"
             expected-failure: "false"
+          - envs: "pixi:failing-env"
+            manifest-path: "envs/pixi.toml"
+            policy-file: "policy.yaml"
+            expected-failure: "true"
 
     steps:
       - name: clone the repository
diff --git a/envs/pixi.toml b/envs/pixi.toml
index 06a5ffd..bcef0d0 100644
--- a/envs/pixi.toml
+++ b/envs/pixi.toml
@@ -1,5 +1,4 @@
 [dependencies]
-numpy = "1.24"
 pandas = "2.1"
 packaging = "23.1"
 
@@ -9,6 +8,11 @@ python = "3.10"
 [feature.py311.dependencies]
 python = "3.11"
 
+[feature.failing.dependencies]
+numpy = "2.1"
+
+
 [environments]
 env1 = { features = ["py310"] }
 env2 = ["py311"]
+failing-env = { features = ["failing"] }

From 35ac1e9526ebb20dcdd9e9ac594578ef3d89f488 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Mon, 8 Dec 2025 23:03:46 +0100
Subject: [PATCH 40/57] also check the default pypi-dependencies

---
 minimum_versions/environments/pixi.py | 21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

diff --git a/minimum_versions/environments/pixi.py b/minimum_versions/environments/pixi.py
index 1426842..e2ba832 100644
--- a/minimum_versions/environments/pixi.py
+++ b/minimum_versions/environments/pixi.py
@@ -86,14 +86,19 @@ def parse_pixi_environment(name: str, manifest_path: pathlib.Path | None):
         raise ValueError(f"Unknown environment: {name}")
 
     if isinstance(env, list):
-        feature_names = env
+        feature_names = ["default"] + env
     elif isinstance(env, dict) and list(env) != ["features"]:
         raise ValueError("Options other than 'features' are not supported.")
     else:
-        feature_names = env["features"]
+        feature_names = ["default"] + env["features"]
 
-    features = [pixi_config.get("dependencies", [])] + [
-        get_in([feature, "dependencies"], all_features) for feature in feature_names
+    features = [
+        (
+            get_in([feature, "dependencies"], all_features)
+            if feature != "default"
+            else pixi_config.get("dependencies", [])
+        )
+        for feature in feature_names
     ]
 
     pins = merge(features)
@@ -102,8 +107,12 @@ def parse_pixi_environment(name: str, manifest_path: pathlib.Path | None):
     warnings = []
 
     pypi_dependencies = {
-        feature: get_in([feature, "pypi-dependencies"], all_features, default=[])
-        for feature in env["features"]
+        feature: (
+            get_in([feature, "pypi-dependencies"], all_features)
+            if feature != "default"
+            else pixi_config.get("pypi-dependencies", [])
+        )
+        for feature in feature_names
     }
     with_pypi_dependencies = {
         feature: bool(deps) for feature, deps in pypi_dependencies.items() if deps

From b5844765da598b3d50efbbd31bfcfce03004dfe2 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Mon, 8 Dec 2025 23:05:48 +0100
Subject: [PATCH 41/57] back to `python=3.9`

---
 envs/pixi.toml | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/envs/pixi.toml b/envs/pixi.toml
index bcef0d0..365e095 100644
--- a/envs/pixi.toml
+++ b/envs/pixi.toml
@@ -2,17 +2,16 @@
 pandas = "2.1"
 packaging = "23.1"
 
+[feature.py39.dependencies]
+python = "3.9"
+
 [feature.py310.dependencies]
 python = "3.10"
 
-[feature.py311.dependencies]
-python = "3.11"
-
 [feature.failing.dependencies]
 numpy = "2.1"
 
-
 [environments]
 env1 = { features = ["py310"] }
-env2 = ["py311"]
+env2 = ["py39"]
 failing-env = { features = ["failing"] }

From 2d1976e7a2f46c88ccd268f6bfd52afd5b7fc11d Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Tue, 9 Dec 2025 19:33:05 +0100
Subject: [PATCH 42/57] support the `no-default-feature` option

---
 minimum_versions/environments/pixi.py       | 15 +++--
 minimum_versions/tests/test_environments.py | 64 +++++++++++++++------
 2 files changed, 57 insertions(+), 22 deletions(-)

diff --git a/minimum_versions/environments/pixi.py b/minimum_versions/environments/pixi.py
index e2ba832..a0b0e01 100644
--- a/minimum_versions/environments/pixi.py
+++ b/minimum_versions/environments/pixi.py
@@ -86,11 +86,18 @@ def parse_pixi_environment(name: str, manifest_path: pathlib.Path | None):
         raise ValueError(f"Unknown environment: {name}")
 
     if isinstance(env, list):
-        feature_names = ["default"] + env
-    elif isinstance(env, dict) and list(env) != ["features"]:
-        raise ValueError("Options other than 'features' are not supported.")
+        feature_names = env
+    elif isinstance(env, dict) and env.keys() - {"features", "no-default-feature"}:
+        raise ValueError(
+            "Options other than 'features' and 'no-default-feature'"
+            f" are not supported. Got {env}."
+        )
+    elif isinstance(env, dict):
+        feature_names = env["features"]
+        if not env.get("no-default-feature", False):
+            feature_names.insert(0, "default")
     else:
-        feature_names = ["default"] + env["features"]
+        raise ValueError("unexpected environment type")
 
     features = [
         (
diff --git a/minimum_versions/tests/test_environments.py b/minimum_versions/tests/test_environments.py
index b315a7d..4db5c34 100644
--- a/minimum_versions/tests/test_environments.py
+++ b/minimum_versions/tests/test_environments.py
@@ -240,20 +240,54 @@ def test_parse_spec_error(self, version_text):
         with pytest.raises(ValueError, match="Unknown version format: .*"):
             environments.pixi.parse_spec("package", version_text)
 
-    def test_parse_pixi_environment(self, monkeypatch):
-        data = textwrap.dedent(
-            """\
-            [dependencies]
-            a = "1.0.*"
-            b = "2.2.*"
+    @pytest.mark.parametrize(
+        ["data", "expected_specs", "expected_warnings"],
+        (
+            pytest.param(
+                textwrap.dedent(
+                    """\
+                    [dependencies]
+                    a = "1.0.*"
+                    b = "2.2.*"
 
-            [feature.feature1.dependencies]
-            c = "3.1.*"
+                    [feature.feature1.dependencies]
+                    c = "3.1.*"
 
-            [environments]
-            env1 = { features = ["feature1"] }
-            """.rstrip()
-        )
+                    [environments]
+                    env1 = { features = ["feature1"] }
+                    """.rstrip()
+                ),
+                [
+                    Spec("a", Version("1.0")),
+                    Spec("b", Version("2.2")),
+                    Spec("c", Version("3.1")),
+                ],
+                [("a", []), ("b", []), ("c", [])],
+                id="default-feature",
+            ),
+            pytest.param(
+                textwrap.dedent(
+                    """\
+                    [dependencies]
+                    a = "1.0.*"
+                    b = "2.2.*"
+
+                    [feature.feature1.dependencies]
+                    c = "3.1.*"
+
+                    [environments]
+                    env1 = { features = ["feature1"], no-default-feature = true }
+                    """.rstrip()
+                ),
+                [Spec("c", Version("3.1"))],
+                [("c", [])],
+                id="no-default-feature",
+            ),
+        ),
+    )
+    def test_parse_pixi_environment(
+        self, monkeypatch, data, expected_specs, expected_warnings
+    ):
         monkeypatch.setattr(
             pathlib.Path, "open", lambda _, mode: io.BytesIO(data.encode())
         )
@@ -264,11 +298,5 @@ def test_parse_pixi_environment(self, monkeypatch):
         actual_specs, actual_warnings = environments.pixi.parse_pixi_environment(
             name, manifest_path
         )
-        expected_specs = [
-            Spec("a", Version("1.0")),
-            Spec("b", Version("2.2")),
-            Spec("c", Version("3.1")),
-        ]
-        expected_warnings = [("a", []), ("b", []), ("c", [])]
         assert actual_specs == expected_specs
         assert actual_warnings == expected_warnings

From 3017270385b739502f385471ab49678722b58838 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Tue, 9 Dec 2025 19:44:38 +0100
Subject: [PATCH 43/57] support analyzing missing features

---
 minimum_versions/environments/pixi.py       |  4 +---
 minimum_versions/tests/test_environments.py | 14 ++++++++++++++
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/minimum_versions/environments/pixi.py b/minimum_versions/environments/pixi.py
index a0b0e01..46b73a1 100644
--- a/minimum_versions/environments/pixi.py
+++ b/minimum_versions/environments/pixi.py
@@ -77,9 +77,7 @@ def parse_pixi_environment(name: str, manifest_path: pathlib.Path | None):
     if environment_definitions is None:
         raise ValueError("Can't find environments in the pixi config.")
 
-    all_features = pixi_config.get("feature")
-    if all_features is None:
-        raise ValueError("No features found in the pixi config.")
+    all_features = pixi_config.get("feature", {})
 
     env = environment_definitions.get(name)
     if env is None:
diff --git a/minimum_versions/tests/test_environments.py b/minimum_versions/tests/test_environments.py
index 4db5c34..38dc664 100644
--- a/minimum_versions/tests/test_environments.py
+++ b/minimum_versions/tests/test_environments.py
@@ -283,6 +283,20 @@ def test_parse_spec_error(self, version_text):
                 [("c", [])],
                 id="no-default-feature",
             ),
+            pytest.param(
+                textwrap.dedent(
+                    """\
+                    [dependencies]
+                    a = "1.0.*"
+
+                    [environments]
+                    env1 = { features = [] }
+                    """.rstrip()
+                ),
+                [Spec("a", Version("1.0"))],
+                [("a", [])],
+                id="missing-features",
+            ),
         ),
     )
     def test_parse_pixi_environment(

From 285aee0767e3dc83d36341bd37664620c2ef9c6a Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Tue, 9 Dec 2025 19:46:23 +0100
Subject: [PATCH 44/57] change the error text for unknown version specs

---
 minimum_versions/environments/pixi.py       | 2 +-
 minimum_versions/tests/test_environments.py | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/minimum_versions/environments/pixi.py b/minimum_versions/environments/pixi.py
index 46b73a1..4296b2d 100644
--- a/minimum_versions/environments/pixi.py
+++ b/minimum_versions/environments/pixi.py
@@ -42,7 +42,7 @@ def parse_spec(name, version_text):
 
         raw_version = lower_pin
     else:
-        raise ValueError(f"Unknown version format: {version_text}")
+        raise ValueError(f"Unsupported version spec: {version_text}")
 
     if raw_version is not None:
         version = Version(raw_version.removesuffix(".*"))
diff --git a/minimum_versions/tests/test_environments.py b/minimum_versions/tests/test_environments.py
index 38dc664..4549b08 100644
--- a/minimum_versions/tests/test_environments.py
+++ b/minimum_versions/tests/test_environments.py
@@ -237,7 +237,7 @@ def test_parse_spec(self, name, version_text, expected_spec, expected_warnings):
 
     @pytest.mark.parametrize("version_text", ("~1.3", "^2.1", "<1.1"))
     def test_parse_spec_error(self, version_text):
-        with pytest.raises(ValueError, match="Unknown version format: .*"):
+        with pytest.raises(ValueError, match="Unsupported version spec: .*"):
             environments.pixi.parse_spec("package", version_text)
 
     @pytest.mark.parametrize(

From fdfa6b61dbe474ba40d6fd5329179e298932dab9 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Tue, 9 Dec 2025 19:53:22 +0100
Subject: [PATCH 45/57] add a note containing the package name

---
 minimum_versions/environments/pixi.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/minimum_versions/environments/pixi.py b/minimum_versions/environments/pixi.py
index 4296b2d..23d7bd6 100644
--- a/minimum_versions/environments/pixi.py
+++ b/minimum_versions/environments/pixi.py
@@ -125,7 +125,11 @@ def parse_pixi_environment(name: str, manifest_path: pathlib.Path | None):
     for feature in with_pypi_dependencies:
         warnings.append((f"feature:{feature}", ["Ignored PyPI dependencies."]))
     for name, pin in pins.items():
-        spec, warnings_ = parse_spec(name, pin)
+        try:
+            spec, warnings_ = parse_spec(name, pin)
+        except ValueError as e:
+            e.add_note(f"package name: {name}")
+            raise
 
         specs.append(spec)
         warnings.append(warnings_)

From f0fd56db4fcecefe26464858b21435234d7d27f8 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Tue, 9 Dec 2025 19:54:51 +0100
Subject: [PATCH 46/57] add more information

---
 minimum_versions/environments/pixi.py | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/minimum_versions/environments/pixi.py b/minimum_versions/environments/pixi.py
index 23d7bd6..4dccb27 100644
--- a/minimum_versions/environments/pixi.py
+++ b/minimum_versions/environments/pixi.py
@@ -124,11 +124,11 @@ def parse_pixi_environment(name: str, manifest_path: pathlib.Path | None):
     }
     for feature in with_pypi_dependencies:
         warnings.append((f"feature:{feature}", ["Ignored PyPI dependencies."]))
-    for name, pin in pins.items():
+    for package_name, pin in pins.items():
         try:
-            spec, warnings_ = parse_spec(name, pin)
+            spec, warnings_ = parse_spec(package_name, pin)
         except ValueError as e:
-            e.add_note(f"package name: {name}")
+            e.add_note(f"environment {name}: {package_name}{pin}")
             raise
 
         specs.append(spec)

From c95acf76683afa1780b21234d69cf63e02c10b57 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Tue, 9 Dec 2025 19:55:06 +0100
Subject: [PATCH 47/57] support dict pins

---
 minimum_versions/environments/pixi.py | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/minimum_versions/environments/pixi.py b/minimum_versions/environments/pixi.py
index 4dccb27..ad3a953 100644
--- a/minimum_versions/environments/pixi.py
+++ b/minimum_versions/environments/pixi.py
@@ -13,12 +13,15 @@
 tight_pin_re = re.compile(rf">=(?P<lower>{_version_re}),<(?P<upper>{_version_re})")
 
 
-def parse_spec(name, version_text):
+def parse_spec(name, version_text: str | dict):
     # "*" => None
     # "x.y.*" => "x.y"
     # ">=x.y.0,<x.(y + 1).0" => "x.y" (+ warning)
     # ">=x.y.*" => "x.y" (+ warning)
 
+    if isinstance(version_text, dict):
+        version_text = version_text.get("version", "*")
+
     warnings = []
     if version_text == "*":
         raw_version = None

From 56aab763eb47a695527bcb4bed97d5fcca371f8a Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Tue, 9 Dec 2025 20:07:24 +0100
Subject: [PATCH 48/57] configure coverage

---
 pyproject.toml | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/pyproject.toml b/pyproject.toml
index 4a3f92c..0e241db 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -72,3 +72,11 @@ fixable = ["I", "TID252"]
 [tool.ruff.lint.flake8-tidy-imports]
 # Disallow all relative imports.
 ban-relative-imports = "all"
+
+[tool.coverage.run]
+source = ["minimum_versions"]
+branch = true
+
+[tool.coverage.report]
+show_missing = true
+exclude_lines = ["pragma: no cover", "if TYPE_CHECKING"]

From 113d767986be786362de9ae335e1adf08c1fafef Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Tue, 9 Dec 2025 20:08:11 +0100
Subject: [PATCH 49/57] check the format detection

---
 minimum_versions/environments/pixi.py       |  8 +++----
 minimum_versions/tests/test_environments.py | 24 ++++++++++++++++++---
 2 files changed, 25 insertions(+), 7 deletions(-)

diff --git a/minimum_versions/environments/pixi.py b/minimum_versions/environments/pixi.py
index ad3a953..c533f3e 100644
--- a/minimum_versions/environments/pixi.py
+++ b/minimum_versions/environments/pixi.py
@@ -67,14 +67,14 @@ def parse_pixi_environment(name: str, manifest_path: pathlib.Path | None):
     with manifest_path.open(mode="rb") as f:
         data = tomllib.load(f)
 
-    if manifest_path.name == "pixi.toml":
-        pixi_config = data
-    else:
-        pixi_config = get_in(["pixi", "tool"], data, None)
+    if manifest_path.name == "pyproject.toml":
+        pixi_config = get_in(["tool", "pixi"], data, None)
         if pixi_config is None:
             raise ValueError(
                 f"The 'tool.pixi' section is missing from {manifest_path}."
             )
+    else:
+        pixi_config = data
 
     environment_definitions = pixi_config.get("environments")
     if environment_definitions is None:
diff --git a/minimum_versions/tests/test_environments.py b/minimum_versions/tests/test_environments.py
index 4549b08..bd37117 100644
--- a/minimum_versions/tests/test_environments.py
+++ b/minimum_versions/tests/test_environments.py
@@ -241,7 +241,7 @@ def test_parse_spec_error(self, version_text):
             environments.pixi.parse_spec("package", version_text)
 
     @pytest.mark.parametrize(
-        ["data", "expected_specs", "expected_warnings"],
+        ["data", "path", "expected_specs", "expected_warnings"],
         (
             pytest.param(
                 textwrap.dedent(
@@ -257,6 +257,7 @@ def test_parse_spec_error(self, version_text):
                     env1 = { features = ["feature1"] }
                     """.rstrip()
                 ),
+                "pixi.toml",
                 [
                     Spec("a", Version("1.0")),
                     Spec("b", Version("2.2")),
@@ -279,6 +280,7 @@ def test_parse_spec_error(self, version_text):
                     env1 = { features = ["feature1"], no-default-feature = true }
                     """.rstrip()
                 ),
+                "pixi.toml",
                 [Spec("c", Version("3.1"))],
                 [("c", [])],
                 id="no-default-feature",
@@ -293,21 +295,37 @@ def test_parse_spec_error(self, version_text):
                     env1 = { features = [] }
                     """.rstrip()
                 ),
+                "pixi.toml",
                 [Spec("a", Version("1.0"))],
                 [("a", [])],
                 id="missing-features",
             ),
+            pytest.param(
+                textwrap.dedent(
+                    """\
+                    [tool.pixi.feature.feature1.dependencies]
+                    c = "3.1.*"
+
+                    [tool.pixi.environments]
+                    env1 = { features = ["feature1"], no-default-feature = true }
+                    """.rstrip()
+                ),
+                "pyproject.toml",
+                [Spec("c", Version("3.1"))],
+                [("c", [])],
+                id="pyproject",
+            ),
         ),
     )
     def test_parse_pixi_environment(
-        self, monkeypatch, data, expected_specs, expected_warnings
+        self, monkeypatch, path, data, expected_specs, expected_warnings
     ):
         monkeypatch.setattr(
             pathlib.Path, "open", lambda _, mode: io.BytesIO(data.encode())
         )
 
         name = "env1"
-        manifest_path = pathlib.Path("pixi.toml")
+        manifest_path = pathlib.Path(path)
 
         actual_specs, actual_warnings = environments.pixi.parse_pixi_environment(
             name, manifest_path

From 4dcc7dcd236aeb34450647c55e56ac93833cb135 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Tue, 9 Dec 2025 20:09:13 +0100
Subject: [PATCH 50/57] raise on unknown features

---
 minimum_versions/environments/pixi.py | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/minimum_versions/environments/pixi.py b/minimum_versions/environments/pixi.py
index c533f3e..59fe6f1 100644
--- a/minimum_versions/environments/pixi.py
+++ b/minimum_versions/environments/pixi.py
@@ -100,6 +100,12 @@ def parse_pixi_environment(name: str, manifest_path: pathlib.Path | None):
     else:
         raise ValueError("unexpected environment type")
 
+    unknown_features = [
+        name for name in feature_names if name != "default" and name not in all_features
+    ]
+    if unknown_features:
+        raise ValueError(f"unknown features: {', '.join(unknown_features)}")
+
     features = [
         (
             get_in([feature, "dependencies"], all_features)

From 81715497315fd6850c334f1e49c30db3f1336354 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Tue, 9 Dec 2025 20:09:42 +0100
Subject: [PATCH 51/57] support no features

---
 minimum_versions/environments/pixi.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/minimum_versions/environments/pixi.py b/minimum_versions/environments/pixi.py
index 59fe6f1..31ad8fd 100644
--- a/minimum_versions/environments/pixi.py
+++ b/minimum_versions/environments/pixi.py
@@ -108,7 +108,7 @@ def parse_pixi_environment(name: str, manifest_path: pathlib.Path | None):
 
     features = [
         (
-            get_in([feature, "dependencies"], all_features)
+            get_in([feature, "dependencies"], all_features, {})
             if feature != "default"
             else pixi_config.get("dependencies", [])
         )

From 2555235114b2aae574e4dccf60a6eb3285d49318 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Tue, 9 Dec 2025 20:10:06 +0100
Subject: [PATCH 52/57] check that `<=` is also detected

---
 minimum_versions/tests/test_environments.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/minimum_versions/tests/test_environments.py b/minimum_versions/tests/test_environments.py
index bd37117..dd93b5c 100644
--- a/minimum_versions/tests/test_environments.py
+++ b/minimum_versions/tests/test_environments.py
@@ -235,7 +235,7 @@ def test_parse_spec(self, name, version_text, expected_spec, expected_warnings):
         assert actual_name == name
         assert actual_warnings == expected_warnings
 
-    @pytest.mark.parametrize("version_text", ("~1.3", "^2.1", "<1.1"))
+    @pytest.mark.parametrize("version_text", ("~1.3", "^2.1", "<1.1", "<=2025.01"))
     def test_parse_spec_error(self, version_text):
         with pytest.raises(ValueError, match="Unsupported version spec: .*"):
             environments.pixi.parse_spec("package", version_text)

From 99672dda38dea13dd5f51b0bdd14d2d7a3ab1c00 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Tue, 9 Dec 2025 20:10:38 +0100
Subject: [PATCH 53/57] check pypi dependencies

---
 minimum_versions/tests/test_environments.py | 36 +++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/minimum_versions/tests/test_environments.py b/minimum_versions/tests/test_environments.py
index dd93b5c..c9b311b 100644
--- a/minimum_versions/tests/test_environments.py
+++ b/minimum_versions/tests/test_environments.py
@@ -300,6 +300,42 @@ def test_parse_spec_error(self, version_text):
                 [("a", [])],
                 id="missing-features",
             ),
+            pytest.param(
+                textwrap.dedent(
+                    """\
+                    [dependencies]
+                    a = "1.0.*"
+
+                    [pypi-dependencies]
+                    b = "3.2.*"
+
+                    [environments]
+                    env1 = { features = [] }
+                    """.rstrip()
+                ),
+                "pixi.toml",
+                [Spec("a", Version("1.0"))],
+                [("feature:default", ["Ignored PyPI dependencies."]), ("a", [])],
+                id="pypi_dependencies-default",
+            ),
+            pytest.param(
+                textwrap.dedent(
+                    """\
+                    [dependencies]
+                    a = "1.0.*"
+
+                    [feature.feat1.pypi-dependencies]
+                    b = "3.2.*"
+
+                    [environments]
+                    env1 = { features = ["feat1"] }
+                    """.rstrip()
+                ),
+                "pixi.toml",
+                [Spec("a", Version("1.0"))],
+                [("feature:feat1", ["Ignored PyPI dependencies."]), ("a", [])],
+                id="pypi_dependencies-feat1",
+            ),
             pytest.param(
                 textwrap.dedent(
                     """\

From 7bad70de5462710af38eb2cd44d70de09e524d36 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Tue, 9 Dec 2025 20:12:12 +0100
Subject: [PATCH 54/57] support local packages

---
 minimum_versions/tests/test_environments.py | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/minimum_versions/tests/test_environments.py b/minimum_versions/tests/test_environments.py
index c9b311b..723bdc4 100644
--- a/minimum_versions/tests/test_environments.py
+++ b/minimum_versions/tests/test_environments.py
@@ -224,6 +224,7 @@ class TestPixiEnvironment:
                 id="patch_pin",
             ),
             pytest.param("e", "*", Spec("e", None), [], id="unpinned"),
+            pytest.param("f", {"path": "."}, Spec("f", None), [], id="source_package"),
         ),
     )
     def test_parse_spec(self, name, version_text, expected_spec, expected_warnings):
@@ -351,6 +352,24 @@ def test_parse_spec_error(self, version_text):
                 [("c", [])],
                 id="pyproject",
             ),
+            pytest.param(
+                textwrap.dedent(
+                    """\
+                    [dependencies]
+                    a = { path = "." }
+
+                    [feature.feature1.dependencies]
+                    c = "3.1.*"
+
+                    [environments]
+                    env1 = { features = ["feature1"] }
+                    """.rstrip()
+                ),
+                "pixi.toml",
+                [Spec("c", Version("3.1"))],
+                [("c", [])],
+                id="local_package",
+            ),
         ),
     )
     def test_parse_pixi_environment(

From 798e579bfcb4e3057d98a62371ca59f9e941eafc Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Tue, 9 Dec 2025 20:23:39 +0100
Subject: [PATCH 55/57] skip the local package, if any

---
 minimum_versions/environments/pixi.py | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/minimum_versions/environments/pixi.py b/minimum_versions/environments/pixi.py
index 31ad8fd..60e634a 100644
--- a/minimum_versions/environments/pixi.py
+++ b/minimum_versions/environments/pixi.py
@@ -115,7 +115,13 @@ def parse_pixi_environment(name: str, manifest_path: pathlib.Path | None):
         for feature in feature_names
     ]
 
-    pins = merge(features)
+    local_package_name = get_in(["package", "name"], pixi_config, None)
+    pins = {
+        name: pin
+        for name, pin in merge(features).items()
+        # skip the local package, if any
+        if name != local_package_name
+    }
 
     specs = []
     warnings = []

From 5e76d15a5f374711439cfde35face2d3a2c91834 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Tue, 9 Dec 2025 20:25:54 +0100
Subject: [PATCH 56/57] properly check that local packages are skipped

---
 minimum_versions/tests/test_environments.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/minimum_versions/tests/test_environments.py b/minimum_versions/tests/test_environments.py
index 723bdc4..1592d31 100644
--- a/minimum_versions/tests/test_environments.py
+++ b/minimum_versions/tests/test_environments.py
@@ -355,6 +355,9 @@ def test_parse_spec_error(self, version_text):
             pytest.param(
                 textwrap.dedent(
                     """\
+                    [package]
+                    name = "a"
+
                     [dependencies]
                     a = { path = "." }
 

From 7420881fc813c3eec2cfbf11fed8e6b91991fd48 Mon Sep 17 00:00:00 2001
From: Justus Magin <keewis@posteo.de>
Date: Wed, 10 Dec 2025 21:13:36 +0100
Subject: [PATCH 57/57] add information about the environments

---
 README.md | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index a11fa60..6c1a61f 100644
--- a/README.md
+++ b/README.md
@@ -48,6 +48,8 @@ Then add a new step to CI.
 
 To analyze conda environments, simply pass the path to the environment file (`env.yaml`) to the `environments` key.
 
+The conda environment file _must_ specify exactly the `conda-forge` channel.
+
 ```yaml
 jobs:
   my-job:
@@ -79,7 +81,9 @@ jobs:
 
 ### pixi
 
-To analyze pixi environments, specify the environment name prefixed with `pixi:` and point to the manifest file using `manifest-path`:
+To analyze pixi environments, specify the environment name prefixed with `pixi:` and point to the manifest file using `manifest-path`.
+
+Any environment must pin the dependencies, which must be exact pins (i.e. `x.y.*` or `>=x.y.0,<x.(y + 1).0`, with the former being strongly encouraged). Lower pins are interpreted as exact pins, while all other forms of pinning are not allowed.
 
 ```yaml
 jobs: