Parse mypy result with regex

Author: tomv564

pyls_mypy/plugin.py

@@ -1,38 +1,45 @@
 # Copyright 2017 Mikael Knutsson
+import re
 from mypy import api as mypy_api
 from pyls import hookimpl
 
+line_pattern = r"(.*):(\d+):(\d+): (\w+): (.*)"
 
-@hookimpl
-def pyls_lint(document):
-    args = ('--ignore-missing-imports',
-            '--incremental',
-            '--show-column-numbers',
-            '--command', document.source)
 
-    report, errors, _ = mypy_api.run(args)
-    diagnostics = []
-    for line in report.splitlines():
-        split = line.split(':', 4)
-        if len(split) == 5:
-            _, lineno, offset, severity, msg = split
-        else:
-            _, lineno, severity, msg = split
-            offset = 0
+def parse_line(line):
+    result = re.match(line_pattern, line)
+    if result:
+        _, lineno, offset, severity, msg = result.groups()
         lineno = int(lineno)
         offset = int(offset)
         errno = 2
-        if severity.strip() == 'error':
+        if severity == 'error':
             errno = 1
-        diagnostics.append({
+        return {
             'source': 'mypy',
             'range': {
                 'start': {'line': lineno - 1, 'character': offset},
                 # There may be a better solution, but mypy does not provide end
                 'end': {'line': lineno - 1, 'character': offset + 1}
             },
-            'message': msg.strip(),
+            'message': msg,
             'severity': errno
-        })
+        }
+
+
+@hookimpl
+def pyls_lint(document):
+    args = ('--ignore-missing-imports',
+            '--incremental',
+            '--show-column-numbers',
+            '--command', document.source)
+
+    report, errors, _ = mypy_api.run(args)
+
+    diagnostics = []
+    for line in report.splitlines():
+        diag = parse_line(line)
+        if diag:
+            diagnostics.append(diag)
 
     return diagnostics

test/test_plugin.py

@@ -5,6 +5,9 @@
 DOC_TYPE_ERR = """{}.append(3)
 """
 
+TEST_LINE = 'main.py:279:8: error: "Request" has no attribute "id"'
+
+
 def test_plugin():
     doc = Document(DOC_URI, DOC_TYPE_ERR)
     diags = plugin.pyls_lint(doc)
@@ -14,3 +17,10 @@ def test_plugin():
     assert diag['message'] == 'Dict[<nothing>, <nothing>] has no attribute "append"'
     assert diag['range']['start'] == {'line': 0, 'character': 0}
     assert diag['range']['end'] == {'line': 0, 'character': 1}
+
+
+def test_parse_line():
+    diag = plugin.parse_line(TEST_LINE)
+    assert diag['message'] == '"Request" has no attribute "id"'
+    assert diag['range']['start'] == {'line': 278, 'character': 8}
+    assert diag['range']['end'] == {'line': 278, 'character': 9}