Fix a crash in LenientFormatStringUtils

Handle `Preconditions.checkNotNull`, which isn't a format method.

PiperOrigin-RevId: 834207706

Author: cushon

core/src/main/java/com/google/errorprone/bugpatterns/formatstring/LenientFormatStringUtils.java

@@ -24,6 +24,7 @@
 import com.google.errorprone.VisitorState;
 import com.google.errorprone.matchers.Matcher;
 import com.sun.source.tree.ExpressionTree;
+import com.sun.source.tree.MethodInvocationTree;
 
 /** Utilities relating to lenient format strings. */
 public final class LenientFormatStringUtils {
@@ -35,7 +36,11 @@ public final class LenientFormatStringUtils {
   public static int getLenientFormatStringPosition(ExpressionTree tree, VisitorState state) {
     for (LenientFormatMethod method : LENIENT_FORMATTING_METHODS) {
       if (method.matcher().matches(tree, state)) {
-        return method.formatStringPosition;
+        if (tree instanceof MethodInvocationTree methodInvocation
+            && method.formatStringPosition < methodInvocation.getArguments().size()) {
+          // e.g. Preconditions.checkNotNull(String) isn't a format method
+          return method.formatStringPosition;
+        }
       }
     }
     return -1;

core/src/test/java/com/google/errorprone/bugpatterns/formatstring/InlineFormatStringTest.java

@@ -266,4 +266,23 @@ void f() {
             """)
         .doTest();
   }
+
+  @Test
+  public void nonFormatMethod() {
+    compilationHelper
+        .addSourceLines(
+            "Test.java",
+            """
+            import com.google.common.base.Preconditions;
+
+            class Test {
+              void f(Object obj) {
+                String format = "hello %s";
+                Preconditions.checkNotNull(format);
+                Preconditions.checkNotNull(obj, format);
+              }
+            }
+            """)
+        .doTest();
+  }
 }