Strip comments and whitespace from javascript resources

third_party/closure_compiler/compile2.py

 #!/usr/bin/python
 # Copyright 2015 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
+from argparse import Action
 
 """Runs Closure compiler on JavaScript files to check for errors and produce
 minified output."""
 
 import argparse
 import os
 import re
 import subprocess
 import sys
 import tempfile
@@ skipping 168 matching lines @@
 
     Return:
       The filepath of the newly created, written, and closed temporary file.
     """
     with tempfile.NamedTemporaryFile(mode="wt", delete=False) as tmp_file:
       self._temp_files.append(tmp_file.name)
       tmp_file.write(contents)
     return tmp_file.name
 
   def check(self, sources, out_file=None, closure_args=None,
-            custom_sources=True):
+            custom_sources=True, enable_chrome_pass=True):
     """Closure compile |sources| while checking for errors.
 
     Args:
       sources: Files to check. sources[0] is the typically the target file.
           sources[1:] are externs and dependencies in topological order. Order
           is not guaranteed if custom_sources is True.
       out_file: A file where the compiled output is written to.
       closure_args: Arguments passed directly to the Closure compiler.
       custom_sources: Whether |sources| was customized by the target (e.g. not
           in GYP dependency order).
@@ skipping 13 matching lines @@
 
     externs = filter(is_extern, externs_and_deps)
     deps = filter(lambda f: not is_extern(f), externs_and_deps)
 
     assert externs or deps or self._target
 
     self._log_debug("Externs: %s" % externs)
     self._log_debug("Dependencies: %s" % deps)
     self._log_debug("Target: %s" % self._target)
 
-    js_args = deps + [self._target] if self._target else []
+    js_args = deps + ([self._target] if self._target else [])
 
     if not custom_sources:
       # TODO(dbeam): compiler.jar automatically detects "@externs" in a --js arg
       # and moves these files to a different AST tree. However, because we use
       # one big funky <include> meta-file, it thinks all the code is one big
       # externs. Just use --js when <include> dies.
 
       cwd, tmp_dir = os.getcwd(), tempfile.gettempdir()
       rel_path = lambda f: os.path.join(os.path.relpath(cwd, tmp_dir), f)
       contents = ['<include src="%s">' % rel_path(f) for f in js_args]
@@ skipping 20 matching lines @@
       args += ["--js_output_file=%s" % out_file]
       args += ["--create_source_map=%s" % (self._MAP_FILE_FORMAT % out_file)]
 
     args_file_content = " %s" % " ".join(args)
     self._log_debug("Args: %s" % args_file_content.strip())
 
     args_file = self._create_temp_file(args_file_content)
     self._log_debug("Args file: %s" % args_file)
 
     runner_args = ["--compiler-args-file=%s" % args_file]
+    if enable_chrome_pass:
+      runner_args += ["--enable_chrome_pass"]
+
     _, stderr = self._run_jar(self._runner_jar, runner_args)
 
     errors = stderr.strip().split("\n\n")
     maybe_summary = errors.pop()
 
-    if re.search(".*error.*warning.*typed", maybe_summary):
+    summary = re.search("(?P<error_count>\d+).*error.*warning", maybe_summary)
+    if summary:
       self._log_debug("Summary: %s" % maybe_summary)
     else:
       # Not a summary. Running the jar failed. Bail.
       self._log_error(stderr)
       self._nuke_temp_files()
       sys.exit(1)
 
-    if errors and out_file:
+    if summary.group('error_count') != "0" and out_file:
       if os.path.exists(out_file):
         os.remove(out_file)
       if os.path.exists(self._MAP_FILE_FORMAT % out_file):
         os.remove(self._MAP_FILE_FORMAT % out_file)
 
     if not custom_sources:
       filtered_errors = self._filter_errors(errors)
       errors = map(self._clean_up_error, filtered_errors)
       output = self._format_errors(errors)
 
@@ skipping 11 matching lines @@
   parser = argparse.ArgumentParser(
       description="Typecheck JavaScript using Closure compiler")
   parser.add_argument("sources", nargs=argparse.ONE_OR_MORE,
                       help="Path to a source file to typecheck")
   parser.add_argument("--custom_sources", action="store_true",
                       help="Whether this rules has custom sources.")
   parser.add_argument("-o", "--out_file",
                       help="A file where the compiled output is written to")
   parser.add_argument("-c", "--closure_args", nargs=argparse.ZERO_OR_MORE,
                       help="Arguments passed directly to the Closure compiler")
+  parser.add_argument("--disable_chrome_pass", action="store_true",
+                      help="Disables the extra Chrome specific processing")
   parser.add_argument("-v", "--verbose", action="store_true",
                       help="Show more information as this script runs")
   opts = parser.parse_args()
 
   checker = Checker(verbose=opts.verbose)
 
-  found_errors, stderr = checker.check(opts.sources, out_file=opts.out_file,
-                                       closure_args=opts.closure_args,
-                                       custom_sources=opts.custom_sources)
+  found_errors, stderr = checker.check(
+      opts.sources,
+      out_file=opts.out_file,
+      closure_args=opts.closure_args,
+      custom_sources=opts.custom_sources,
+      enable_chrome_pass=not opts.disable_chrome_pass)
 
   if found_errors:
     if opts.custom_sources:
       print stderr
     sys.exit(1)