third_party/closure_compiler/checker.py

   1 #!/usr/bin/python
   2 # Copyright 2014 The Chromium Authors. All rights reserved.
   3 # Use of this source code is governed by a BSD-style license that can be
   4 # found in the LICENSE file.
   5
   6 """Runs Closure compiler on a JavaScript file to check for errors."""
   7
   8 import argparse
   9 import os
  10 import re
  11 import subprocess
  12 import sys
  13 import tempfile
  14
  15 import build.inputs
  16 import processor
  17 import error_filter
  18
  19
  20 class Checker(object):
  21   """Runs the Closure compiler on a given source file and returns the
  22   success/errors."""
  23
  24   _COMMON_CLOSURE_ARGS = [
  25     "--accept_const_keyword",
  26     "--jscomp_error=accessControls",
  27     "--jscomp_error=ambiguousFunctionDecl",
  28     "--jscomp_error=checkStructDictInheritance",
  29     "--jscomp_error=checkTypes",
  30     "--jscomp_error=checkVars",
  31     "--jscomp_error=constantProperty",
  32     "--jscomp_error=deprecated",
  33     "--jscomp_error=externsValidation",
  34     "--jscomp_error=globalThis",
  35     "--jscomp_error=invalidCasts",
  36     "--jscomp_error=missingProperties",
  37     "--jscomp_error=missingReturn",
  38     "--jscomp_error=nonStandardJsDocs",
  39     "--jscomp_error=suspiciousCode",
  40     "--jscomp_error=undefinedNames",
  41     "--jscomp_error=undefinedVars",
  42     "--jscomp_error=unknownDefines",
  43     "--jscomp_error=uselessCode",
  44     "--jscomp_error=visibility",
  45     "--language_in=ECMASCRIPT5_STRICT",
  46     "--summary_detail_level=3",
  47   ]
  48
  49   # These are the extra flags used when compiling in 'strict' mode.
  50   # Flags that are normally disabled are turned on for strict mode.
  51   _STRICT_CLOSURE_ARGS = [
  52     "--jscomp_error=reportUnknownTypes",
  53     "--jscomp_error=duplicate",
  54     "--jscomp_error=misplacedTypeAnnotation",
  55   ]
  56
  57   _DISABLED_CLOSURE_ARGS = [
  58     # TODO(dbeam): happens when the same file is <include>d multiple times.
  59     "--jscomp_off=duplicate",
  60     # TODO(fukino): happens when cr.defineProperty() has a type annotation.
  61     # Avoiding parse-time warnings needs 2 pass compiling. crbug.com/421562.
  62     "--jscomp_off=misplacedTypeAnnotation",
  63   ]
  64
  65   _JAR_COMMAND = [
  66     "java",
  67     "-jar",
  68     "-Xms1024m",
  69     "-client",
  70     "-XX:+TieredCompilation"
  71   ]
  72
  73   _found_java = False
  74
  75   def __init__(self, verbose=False, strict=False):
  76     current_dir = os.path.join(os.path.dirname(__file__))
  77     self._runner_jar = os.path.join(current_dir, "runner", "runner.jar")
  78     self._temp_files = []
  79     self._verbose = verbose
  80     self._strict = strict
  81     self._error_filter = error_filter.PromiseErrorFilter()
  82
  83   def _clean_up(self):
  84     if not self._temp_files:
  85       return
  86
  87     self._debug("Deleting temporary files: %s" % ", ".join(self._temp_files))
  88     for f in self._temp_files:
  89       os.remove(f)
  90     self._temp_files = []
  91
  92   def _debug(self, msg, error=False):
  93     if self._verbose:
  94       print "(INFO) %s" % msg
  95
  96   def _error(self, msg):
  97     print >> sys.stderr, "(ERROR) %s" % msg
  98     self._clean_up()
  99
 100   def _common_args(self):
 101     """Returns an array of the common closure compiler args."""
 102     if self._strict:
 103       return self._COMMON_CLOSURE_ARGS + self._STRICT_CLOSURE_ARGS
 104     return self._COMMON_CLOSURE_ARGS + self._DISABLED_CLOSURE_ARGS
 105
 106   def _run_command(self, cmd):
 107     """Runs a shell command.
 108
 109     Args:
 110         cmd: A list of tokens to be joined into a shell command.
 111
 112     Return:
 113         True if the exit code was 0, else False.
 114     """
 115     cmd_str = " ".join(cmd)
 116     self._debug("Running command: %s" % cmd_str)
 117
 118     devnull = open(os.devnull, "w")
 119     return subprocess.Popen(
 120         cmd_str, stdout=devnull, stderr=subprocess.PIPE, shell=True)
 121
 122   def _check_java_path(self):
 123     """Checks that `java` is on the system path."""
 124     if not self._found_java:
 125       proc = self._run_command(["which", "java"])
 126       proc.communicate()
 127       if proc.returncode == 0:
 128         self._found_java = True
 129       else:
 130         self._error("Cannot find java (`which java` => %s)" % proc.returncode)
 131
 132     return self._found_java
 133
 134   def _run_jar(self, jar, args=None):
 135     args = args or []
 136     self._check_java_path()
 137     return self._run_command(self._JAR_COMMAND + [jar] + args)
 138
 139   def _fix_line_number(self, match):
 140     """Changes a line number from /tmp/file:300 to /orig/file:100.
 141
 142     Args:
 143         match: A re.MatchObject from matching against a line number regex.
 144
 145     Returns:
 146         The fixed up /file and :line number.
 147     """
 148     real_file = self._processor.get_file_from_line(match.group(1))
 149     return "%s:%d" % (os.path.abspath(real_file.file), real_file.line_number)
 150
 151   def _fix_up_error(self, error):
 152     """Filter out irrelevant errors or fix line numbers.
 153
 154     Args:
 155         error: A Closure compiler error (2 line string with error and source).
 156
 157     Return:
 158         The fixed up error string (blank if it should be ignored).
 159     """
 160     if " first declared in " in error:
 161       # Ignore "Variable x first declared in /same/file".
 162       return ""
 163
 164     expanded_file = self._expanded_file
 165     fixed = re.sub("%s:(\d+)" % expanded_file, self._fix_line_number, error)
 166     return fixed.replace(expanded_file, os.path.abspath(self._file_arg))
 167
 168   def _format_errors(self, errors):
 169     """Formats Closure compiler errors to easily spot compiler output."""
 170     errors = filter(None, errors)
 171     contents = "\n## ".join("\n\n".join(errors).splitlines())
 172     return "## %s" % contents if contents else ""
 173
 174   def _create_temp_file(self, contents):
 175     with tempfile.NamedTemporaryFile(mode="wt", delete=False) as tmp_file:
 176       self._temp_files.append(tmp_file.name)
 177       tmp_file.write(contents)
 178     return tmp_file.name
 179
 180   def run_js_check(self, sources, externs=None):
 181     if not self._check_java_path():
 182       return 1, ""
 183
 184     args = ["--js=%s" % s for s in sources]
 185     if externs:
 186       args += ["--externs=%s" % e for e in externs]
 187     args_file_content = " %s" % " ".join(self._common_args() + args)
 188     self._debug("Args: %s" % args_file_content.strip())
 189
 190     args_file = self._create_temp_file(args_file_content)
 191     self._debug("Args file: %s" % args_file)
 192
 193     runner_args = ["--compiler-args-file=%s" % args_file]
 194     runner_cmd = self._run_jar(self._runner_jar, args=runner_args)
 195     _, stderr = runner_cmd.communicate()
 196
 197     errors = stderr.strip().split("\n\n")
 198     self._debug("Summary: %s" % errors.pop())
 199
 200     self._clean_up()
 201
 202     return errors, stderr
 203
 204   def check(self, source_file, depends=None, externs=None):
 205     """Closure compile a file and check for errors.
 206
 207     Args:
 208         source_file: A file to check.
 209         depends: Other files that would be included with a <script> earlier in
 210             the page.
 211         externs: @extern files that inform the compiler about custom globals.
 212
 213     Returns:
 214         (has_errors, output) A boolean indicating if there were errors and the
 215             Closure compiler output (as a string).
 216     """
 217     depends = depends or []
 218     externs = externs or set()
 219
 220     if not self._check_java_path():
 221       return 1, ""
 222
 223     self._debug("FILE: %s" % source_file)
 224
 225     if source_file.endswith("_externs.js"):
 226       self._debug("Skipping externs: %s" % source_file)
 227       return
 228
 229     self._file_arg = source_file
 230
 231     tmp_dir = tempfile.gettempdir()
 232     rel_path = lambda f: os.path.join(os.path.relpath(os.getcwd(), tmp_dir), f)
 233
 234     includes = [rel_path(f) for f in depends + [source_file]]
 235     contents = ['<include src="%s">' % i for i in includes]
 236     meta_file = self._create_temp_file("\n".join(contents))
 237     self._debug("Meta file: %s" % meta_file)
 238
 239     self._processor = processor.Processor(meta_file)
 240     self._expanded_file = self._create_temp_file(self._processor.contents)
 241     self._debug("Expanded file: %s" % self._expanded_file)
 242
 243     errors, stderr = self.run_js_check([self._expanded_file], externs)
 244
 245     # Filter out false-positive promise chain errors.
 246     # See https://github.com/google/closure-compiler/issues/715 for details.
 247     errors = self._error_filter.filter(errors);
 248
 249     output = self._format_errors(map(self._fix_up_error, errors))
 250     if errors:
 251       prefix = "\n" if output else ""
 252       self._error("Error in: %s%s%s" % (source_file, prefix, output))
 253     elif output:
 254       self._debug("Output: %s" % output)
 255
 256     return bool(errors), output
 257
 258   def check_multiple(self, sources):
 259     """Closure compile a set of files and check for errors.
 260
 261     Args:
 262         sources: An array of files to check.
 263
 264     Returns:
 265         (has_errors, output) A boolean indicating if there were errors and the
 266             Closure compiler output (as a string).
 267     """
 268
 269     errors, stderr = self.run_js_check(sources)
 270     return bool(errors), stderr
 271
 272 if __name__ == "__main__":
 273   parser = argparse.ArgumentParser(
 274       description="Typecheck JavaScript using Closure compiler")
 275   parser.add_argument("sources", nargs=argparse.ONE_OR_MORE,
 276                       help="Path to a source file to typecheck")
 277   single_file_group = parser.add_mutually_exclusive_group()
 278   single_file_group.add_argument("--single-file", dest="single_file",
 279                                  action="store_true",
 280                                  help="Process each source file individually")
 281   single_file_group.add_argument("--no-single-file", dest="single_file",
 282                                  action="store_false",
 283                                  help="Process all source files as a group")
 284   parser.add_argument("-d", "--depends", nargs=argparse.ZERO_OR_MORE)
 285   parser.add_argument("-e", "--externs", nargs=argparse.ZERO_OR_MORE)
 286   parser.add_argument("-o", "--out_file", help="A place to output results")
 287   parser.add_argument("-v", "--verbose", action="store_true",
 288                       help="Show more information as this script runs")
 289   parser.add_argument("--strict", action="store_true",
 290                       help="Enable strict type checking")
 291   parser.add_argument("--success-stamp",
 292                       help="Timestamp file to update upon success")
 293
 294   parser.set_defaults(single_file=True, strict=False)
 295   opts = parser.parse_args()
 296
 297   depends = opts.depends or []
 298   externs = opts.externs or set()
 299
 300   checker = Checker(verbose=opts.verbose, strict=opts.strict)
 301   if opts.single_file:
 302     for source in opts.sources:
 303       depends, externs = build.inputs.resolve_recursive_dependencies(
 304           source,
 305           depends,
 306           externs)
 307       has_errors, _ = checker.check(source, depends=depends, externs=externs)
 308       if has_errors:
 309         sys.exit(1)
 310
 311       if opts.out_file:
 312         out_dir = os.path.dirname(opts.out_file)
 313         if not os.path.exists(out_dir):
 314           os.makedirs(out_dir)
 315         # TODO(dbeam): write compiled file to |opts.out_file|.
 316         open(opts.out_file, "w").write("")
 317   else:
 318     has_errors, errors = checker.check_multiple(opts.sources)
 319     if has_errors:
 320       print errors
 321       sys.exit(1)
 322
 323   if opts.success_stamp:
 324     with open(opts.success_stamp, 'w'):
 325       os.utime(opts.success_stamp, None)