DevTools: check BUILD.gn file as part of PRESUBMIT

third_party/WebKit/Source/devtools/PRESUBMIT.py

 # Copyright (C) 2014 Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 # copyright notice, this list of conditions and the following disclaimer
@@ skipping 26 matching lines @@
 def _CheckNodeAndNPMModules(input_api, output_api):
     node_script_path = input_api.os_path.join(input_api.PresubmitLocalPath(), "scripts", "install_node_deps.py")
     process = input_api.subprocess.Popen(
         [input_api.python_executable, node_script_path], stdout=input_api.subprocess.PIPE, stderr=input_api.subprocess.STDOUT)
     out, _ = process.communicate()
     if process.returncode != 0:
         return [output_api.PresubmitError(out)]
     return [output_api.PresubmitNotifyResult(out)]
 
 
+def _CheckBuildGN(input_api, output_api):
+    original_sys_path = sys.path
+    try:
+        sys.path = sys.path + [input_api.os_path.join(input_api.PresubmitLocalPath(), "scripts")]
+        import install_node_deps
+    finally:
+        sys.path = original_sys_path
+
+    node_path, _ = install_node_deps.resolve_node_paths()
+
+    script_path = input_api.os_path.join(input_api.PresubmitLocalPath(), "scripts", "check_gn.js")
+    process = input_api.subprocess.Popen(
+        [node_path, script_path], stdout=input_api.subprocess.PIPE, stderr=input_api.subprocess.STDOUT)
+    out, _ = process.communicate()
+
+    if process.returncode != 0:
+        return [output_api.PresubmitError(out)]
+    return [output_api.PresubmitNotifyResult(out)]
+
+
 def _CheckFormat(input_api, output_api):
 
     def popen(args):
         return input_api.subprocess.Popen(args=args, stdout=input_api.subprocess.PIPE, stderr=input_api.subprocess.STDOUT)
 
     affected_files = _getAffectedJSFiles(input_api)
     if len(affected_files) == 0:
         return []
     original_sys_path = sys.path
     try:
@@ skipping 121 matching lines @@
             if "/deep/" in line:
                 results.append(output_api.PresubmitError(("%s:%d uses /deep/ selector") % (f.LocalPath(), line_number)))
             if "::shadow" in line:
                 results.append(output_api.PresubmitError(("%s:%d uses ::shadow selector") % (f.LocalPath(), line_number)))
     return results
 
 
 def CheckChangeOnUpload(input_api, output_api):
     results = []
     results.extend(_CheckNodeAndNPMModules(input_api, output_api))
+    results.extend(_CheckBuildGN(input_api, output_api))
     results.extend(_CheckFormat(input_api, output_api))
     results.extend(_CheckDevtoolsStyle(input_api, output_api))
     results.extend(_CompileDevtoolsFrontend(input_api, output_api))
     results.extend(_CheckConvertSVGToPNGHashes(input_api, output_api))
     results.extend(_CheckOptimizePNGHashes(input_api, output_api))
     results.extend(_CheckCSSViolations(input_api, output_api))
     return results
 
 
 def CheckChangeOnCommit(input_api, output_api):
@@ skipping 13 matching lines @@
 def _getAffectedJSFiles(input_api):
     local_paths = [f.AbsoluteLocalPath() for f in input_api.AffectedFiles() if f.Action() != "D"]
     devtools_root = input_api.PresubmitLocalPath()
     devtools_front_end = input_api.os_path.join(devtools_root, "front_end")
     devtools_scripts = input_api.os_path.join(devtools_root, "scripts")
     affected_js_files = [
         file_name for file_name in local_paths
         if (devtools_front_end in file_name or devtools_scripts in file_name) and file_name.endswith(".js")
     ]
     return [input_api.os_path.relpath(file_name, devtools_root) for file_name in affected_js_files]