Add presubmit check for long paths

Bug: 612667
Change-Id: I6bd52794bf6122813770338a93509d295bf4a7cb
Reviewed-on: https://chromium-review.googlesource.com/1060458Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Commit-Queue: Stephen Martinis <martiniss@chromium.org>
Cr-Commit-Position: refs/heads/master@{#565452}

PRESUBMIT.py

@@ -585,6 +585,12 @@ _IPC_ENUM_TRAITS_DEPRECATED = (
     'See http://www.chromium.org/Home/chromium-security/education/'
     'security-tips-for-ipc')
 
+_LONG_PATH_ERROR = (
+    'Some files included in this CL have file names that are too long (> 200'
+    ' characters). If committed, these files will cause issues on Windows. See'
+    ' https://crbug.com/612667 for more details.'
+)
+
 _JAVA_MULTIPLE_DEFINITION_EXCLUDED_PATHS = [
     r".*[\\\/]BuildHooksAndroidImpl\.java",
     r".*[\\\/]ClassRegisterImpl\.java",
@@ -2827,6 +2833,7 @@ def _CommonChecks(input_api, output_api):
   results.extend(_CheckNoDeprecatedJs(input_api, output_api))
   results.extend(_CheckParseErrors(input_api, output_api))
   results.extend(_CheckForIPCRules(input_api, output_api))
+  results.extend(_CheckForLongPathnames(input_api, output_api))
   results.extend(_CheckForIncludeGuards(input_api, output_api))
   results.extend(_CheckForWindowsLineEndings(input_api, output_api))
   results.extend(_CheckSingletonInHeaders(input_api, output_api))
@@ -3036,6 +3043,24 @@ def _CheckForIPCRules(input_api, output_api):
     return []
 
 
+def _CheckForLongPathnames(input_api, output_api):
+  """Check to make sure no files being submitted have long paths.
+  This causes issues on Windows.
+  """
+  problems = []
+  for f in input_api.AffectedSourceFiles(None):
+    local_path = f.LocalPath()
+    # Windows has a path limit of 260 characters. Limit path length to 200 so
+    # that we have some extra for the prefix on dev machines and the bots.
+    if len(local_path) > 200:
+      problems.append(local_path)
+
+  if problems:
+    return [output_api.PresubmitError(_LONG_PATH_ERROR, problems)]
+  else:
+    return []
+
+
 def _CheckForIncludeGuards(input_api, output_api):
   """Check that header files have proper guards against multiple inclusion.
   If a file should not have such guards (and it probably should) then it