Make javac.py output colorful

build/android/gyp/javac.py

 #!/usr/bin/env python
 #
 # Copyright 2013 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.
 
 import fnmatch
 import optparse
 import os
+import re
 import sys
 
 from util import build_utils
 from util import md5_check
 
+sys.path.append(build_utils.COLORAMA_ROOT)
+import colorama
+
+
+def ColorJavacOutput(output):
+  # Disable line-too-long.
+  # pylint: disable=C0301
+  fileline_prefix = '(?P<fileline>(?P<file>[-.\w/\\]+.java):(?P<line>[0-9]+):)'
+  # ../base/android/java/src/org/chromium/base/library_loader/ProcessInitException.java:10: warning: [serial] serializable class org.chromium.base.library_loader.ProcessInitException has no definition of serialVersionUID

[Ted C, 2014/05/19 23:56:52]

personally, I would probably drop the example lines, but if you want to keep
them, then I would add a comment line above them to make it easier to mentally
parse (i.e. Example warning output line:)

+  warning_re = re.compile(
+      fileline_prefix + '(?P<full_message> warning: (?P<message>.*))$')
+  # ../base/android/java/src/org/chromium/base/ActivityState.java:44: non-static method foo() cannot be referenced from a static context
+  error_re = re.compile(
+      fileline_prefix + '(?P<full_message> (?P<message>.*))$')
+  # public class ProcessInitException extends Exception {
+  #        ^
+  marker_re = re.compile(r'\s*(?P<marker>\^)\s*$')
+  # pylint: enable=C0301
+
+  warning_color = ['full_message', colorama.Fore.YELLOW + colorama.Style.DIM]
+  error_color = ['full_message', colorama.Fore.MAGENTA + colorama.Style.BRIGHT]
+  marker_color = ['marker',  colorama.Fore.BLUE + colorama.Style.BRIGHT]
+
+  def Colorize(line, regex, color):
+    match = regex.match(line)
+    start = match.start(color[0])
+    end = match.end(color[0])
+    return (line[:start]
+            + color[1] + line[start:end]
+            + colorama.Fore.RESET + colorama.Style.RESET_ALL
+            + line[end:])
+
+  def ApplyColor(line):
+    if warning_re.match(line):
+      line = Colorize(line, warning_re, warning_color)
+    elif error_re.match(line):
+      line = Colorize(line, error_re, error_color)
+    elif marker_re.match(line):
+      line = Colorize(line, marker_re, marker_color)
+    return line
+
+  return '\n'.join(map(ApplyColor, output.split('\n')))
+
 
 def DoJavac(options, args):
   output_dir = options.output_dir
 
   src_gendirs = build_utils.ParseGypList(options.src_gendirs)
   java_files = args + build_utils.FindInDirectories(src_gendirs, '*.java')
   if options.javac_includes:
     javac_includes = build_utils.ParseGypList(options.javac_includes)
     filtered_java_files = []
     for f in java_files:
@@ skipping 32 matching lines @@
 
   javac_cmd = ['javac'] + javac_args + java_files
 
   def Compile():
     # Delete the classes directory. This ensures that all .class files in the
     # output are actually from the input .java files. For example, if a .java
     # file is deleted or an inner class is removed, the classes directory should
     # not contain the corresponding old .class file after running this action.
     build_utils.DeleteDirectory(output_dir)
     build_utils.MakeDirectory(output_dir)
-    build_utils.CheckOutput(javac_cmd, print_stdout=options.chromium_code)
+    build_utils.CheckOutput(
+        javac_cmd,
+        print_stdout=options.chromium_code,
+        stderr_filter=ColorJavacOutput)
+
 
   record_path = '%s/javac.md5.stamp' % options.output_dir
   md5_check.CallAndRecordIfStale(
       Compile,
       record_path=record_path,
       input_paths=java_files + jar_inputs,
       input_strings=javac_cmd)
 
 
 def main():
+  colorama.init()
+
   parser = optparse.OptionParser()
   parser.add_option('--src-gendirs',
       help='Directories containing generated java files.')
   parser.add_option('--javac-includes',
       help='A list of file patterns. If provided, only java files that match' +
         'one of the patterns will be compiled.')
   parser.add_option('--classpath', help='Classpath for javac.')
   parser.add_option('--output-dir', help='Directory for javac output.')
   parser.add_option('--stamp', help='Path to touch on success.')
   parser.add_option('--chromium-code', type='int', help='Whether code being '
                     'compiled should be built with stricter warnings for '
                     'chromium code.')
 
   options, args = parser.parse_args()
 
   DoJavac(options, args)
 
   if options.stamp:
     build_utils.Touch(options.stamp)
 
 
 if __name__ == '__main__':
   sys.exit(main())