fix: warn about more source file problems

Author: nedbat

CHANGES.rst

@@ -29,6 +29,11 @@ Unreleased
 - Fix: Complex conditionals over excluded lines could have incorrectly reported
   a missing branch (`issue 1271`_). This is now fixed.
 
+- Fix: More exceptions are now handled when trying to parse source files for
+  reporting.  Problems that used to terminate coverage.py can now be handled
+  with ``[report] ignore_errors``.  This helps with plugins failing to read
+  files (`django_coverage_plugin issue 78`_).
+
 - Fix: Removed another vestige of jQuery from the source tarball
   (`issue 840`_).
 
@@ -37,6 +42,7 @@ Unreleased
   I'd rather not "fix" unsupported interfaces, it's actually nicer with a
   default value.
 
+.. _django_coverage_plugin issue 78: https://github.com/nedbat/django_coverage_plugin/issues/78
 .. _issue 1147: https://github.com/nedbat/coveragepy/issues/1147
 .. _issue 1271: https://github.com/nedbat/coveragepy/issues/1271
 .. _issue 1273: https://github.com/nedbat/coveragepy/issues/1273

coverage/python.py

@@ -57,9 +57,7 @@ def get_python_source(filename):
             break
     else:
         # Couldn't find source.
-        exc_msg = f"No source for code: '{filename}'.\n"
-        exc_msg += "Aborting report output, consider using -i."
-        raise NoSource(exc_msg)
+        raise NoSource(f"No source for code: '{filename}'.")
 
     # Replace \f because of http://bugs.python.org/issue19035
     source = source.replace(b'\f', b' ')

coverage/report.py

@@ -5,7 +5,7 @@
 
 import sys
 
-from coverage.exceptions import CoverageException, NoSource, NotPython
+from coverage.exceptions import CoverageException, NotPython
 from coverage.files import prep_patterns, FnmatchMatcher
 from coverage.misc import ensure_dir_for_file, file_be_gone
 
@@ -70,9 +70,6 @@ def get_analysis_to_report(coverage, morfs):
     for fr in sorted(file_reporters):
         try:
             analysis = coverage._analyze(fr)
-        except NoSource:
-            if not config.ignore_errors:
-                raise
         except NotPython:
             # Only report errors for .py files, and only if we didn't
             # explicitly suppress those errors.
@@ -84,5 +81,11 @@ def get_analysis_to_report(coverage, morfs):
                     coverage._warn(msg, slug="couldnt-parse")
                 else:
                     raise
+        except Exception as exc:
+            if config.ignore_errors:
+                msg = f"Couldn't parse '{fr.filename}': {exc}".rstrip()
+                coverage._warn(msg, slug="couldnt-parse")
+            else:
+                raise
         else:
             yield (fr, analysis)

tests/test_xml.py

@@ -135,7 +135,12 @@ def test_no_source(self):
         cov = coverage.Coverage()
         self.start_import_stop(cov, "innocuous")
         os.remove("innocuous.py")
-        cov.xml_report(ignore_errors=True)
+        with pytest.warns(Warning) as warns:
+            cov.xml_report(ignore_errors=True)
+        assert_coverage_warnings(
+            warns,
+            re.compile(r"Couldn't parse '.*innocuous.py'. \(couldnt-parse\)"),
+            )
         self.assert_exists("coverage.xml")
 
     def test_filename_format_showing_everything(self):