Add presubmit check for useless forward declarations.
Borrowed from Chromium.
Change-Id: I421ef1cc20f28e03b00ed91a765a64922394c76b
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/82110
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
diff --git a/PRESUBMIT.py b/PRESUBMIT.py
index 89c19b5..3eea4fe 100644
--- a/PRESUBMIT.py
+++ b/PRESUBMIT.py
@@ -293,6 +293,7 @@
tests_added.append(path)
return results
+
def _CheckPNGFormat(input_api, output_api):
"""Checks that .png files have a format that will be considered valid by our
test runners. If a file ends with .png, then it must be of the form
@@ -309,6 +310,54 @@
'PNG file %s does not have the correct format' % f.LocalPath()))
return results
+
+def _CheckUselessForwardDeclarations(input_api, output_api):
+ """Checks that added or removed lines in non third party affected
+ header files do not lead to new useless class or struct forward
+ declaration.
+ """
+ results = []
+ class_pattern = input_api.re.compile(r'^class\s+(\w+);$',
+ input_api.re.MULTILINE)
+ struct_pattern = input_api.re.compile(r'^struct\s+(\w+);$',
+ input_api.re.MULTILINE)
+ for f in input_api.AffectedFiles(include_deletes=False):
+ if f.LocalPath().startswith('third_party'):
+ continue
+
+ if not f.LocalPath().endswith('.h'):
+ continue
+
+ contents = input_api.ReadFile(f)
+ fwd_decls = input_api.re.findall(class_pattern, contents)
+ fwd_decls.extend(input_api.re.findall(struct_pattern, contents))
+
+ useless_fwd_decls = []
+ for decl in fwd_decls:
+ count = sum(
+ 1
+ for _ in input_api.re.finditer(r'\b%s\b' %
+ input_api.re.escape(decl), contents))
+ if count == 1:
+ useless_fwd_decls.append(decl)
+
+ if not useless_fwd_decls:
+ continue
+
+ for line in f.GenerateScmDiff().splitlines():
+ if (line.startswith('-') and not line.startswith('--') or
+ line.startswith('+') and not line.startswith('++')):
+ for decl in useless_fwd_decls:
+ if input_api.re.search(r'\b%s\b' % decl, line[1:]):
+ results.append(
+ output_api.PresubmitPromptWarning(
+ '%s: %s forward declaration is no longer needed' %
+ (f.LocalPath(), decl)))
+ useless_fwd_decls.remove(decl)
+
+ return results
+
+
def CheckChangeOnUpload(input_api, output_api):
results = []
results.extend(_CheckUnwantedDependencies(input_api, output_api))
@@ -320,6 +369,7 @@
results.extend(_CheckIncludeOrder(input_api, output_api))
results.extend(_CheckTestDuplicates(input_api, output_api))
results.extend(_CheckPNGFormat(input_api, output_api))
+ results.extend(_CheckUselessForwardDeclarations(input_api, output_api))
author = input_api.change.author_email
if author and author not in _KNOWN_ROBOTS:
