Better msg when gitpython fails

readthedocs/projects/exceptions.py

@@ -38,7 +38,11 @@ class RepositoryError(BuildEnvironmentError):
         'Private repositories are not supported.',
     )
 
-    INVALID_SUBMODULES = _('One or more submodule URLs are not valid: {}.',)
+    INVALID_SUBMODULES = _('One or more submodule URLs are not valid: {}.')
+    INVALID_SUBMODULES_PATH = _(
+        'One or more submodule paths are not valid. '
+        'Check that all your submodules in .gitmodules are used.'
+    )
 
     DUPLICATED_RESERVED_VERSIONS = _(
         'You can not have two versions with the name latest or stable.',

readthedocs/rtd_tests/tests/test_backend.py

@@ -3,6 +3,7 @@
 import os
 from os.path import exists
 from tempfile import mkdtemp
+import textwrap
 
 import django_dynamic_fixture as fixture
 from django.contrib.auth.models import User
@@ -189,6 +190,23 @@ def test_check_invalid_submodule_urls(self):
             RepositoryError.INVALID_SUBMODULES.format(['invalid']),
         )
 
+    def test_invalid_submodule_path(self):
+        repo_path = self.project.repo
+        gitmodules_path = os.path.join(repo_path, '.gitmodules')
+
+        with open(gitmodules_path, 'w+') as f:
+            content = textwrap.dedent("""
+                [submodule "not-valid-path"]
+                    path = not-valid-path
+                    url = https://github.com/readthedocs/readthedocs.org
+            """)
+            f.write(content)
+
+        repo = self.project.vcs_repo()
+        repo.working_dir = repo_path
+        with self.assertRaises(RepositoryError, msg=RepositoryError.INVALID_SUBMODULES_PATH):
+            repo.update_submodules(self.dummy_conf)
+
     @patch('readthedocs.projects.models.Project.checkout_path')
     def test_fetch_clean_tags_and_branches(self, checkout_path):
         upstream_repo = self.project.repo

readthedocs/vcs_support/backends/git.py

@@ -80,8 +80,7 @@ def are_submodules_available(self, config):
             return False
 
         # Keep compatibility with previous projects
-        repo = git.Repo(self.working_dir)
-        return bool(repo.submodules)
+        return bool(self.submodules)
 
     def validate_submodules(self, config):
         """
@@ -104,8 +103,7 @@ def validate_submodules(self, config):
         Returns `False` if at least one submodule is invalid.
         Returns the list of invalid submodules.
         """
-        repo = git.Repo(self.working_dir)
-        submodules = {sub.path: sub for sub in repo.submodules}
+        submodules = {sub.path: sub for sub in self.submodules}
 
         for sub_path in config.submodules.exclude:
             path = sub_path.rstrip('/')
@@ -222,6 +220,16 @@ def commit(self):
             return stdout.strip()
         return None
 
+    @property
+    def submodules(self):
+        try:
+            repo = git.Repo(self.working_dir)
+            return list(repo.submodules)
+        except InvalidGitRepositoryError:
+            raise RepositoryError(
+                RepositoryError.INVALID_SUBMODULES_PATH,
+            )
+
     def checkout(self, identifier=None):
         """Checkout to identifier or latest."""
         super().checkout()