Lay groudwork to Closure compile JavaScript

third_party/closure_compiler/checker.py

Index: third_party/closure_compiler/checker.py
diff --git a/third_party/closure_compiler/checker.py b/third_party/closure_compiler/checker.py
new file mode 100644
index 0000000000000000000000000000000000000000..ef35ff407c6b44fc15cbd1114a2228c3ddc78d91
--- /dev/null
+++ b/third_party/closure_compiler/checker.py
@@ -0,0 +1,198 @@
+# Copyright 2014 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 os
+import re
+import subprocess
+import sys
+import tempfile
+
+
+
+class LineNumber(object):
+  def __init__(self, file, line_number):
+    self.file = file
+    self.line_number = line_number
+
+
+class LineCount(object):
+  def __init__(self, file, line_count):
+    self.file = file
+    self.line_count = line_count
+
+
+class Checker(object):
+  _common_closure_args = [
+    "--accept_const_keyword",
+    "--language_in=ECMASCRIPT5",
+    "--summary_detail_level=3",
+    "--warning_level=VERBOSE",
+    "--jscomp_error=accessControls",
+    "--jscomp_error=ambiguousFunctionDecl",
+    "--jscomp_error=checkEventfulObjectDisposal",

[arv (Not doing code reviews), 2014/07/16 18:33:02]

We do not depend on dispose pattern. It is a bad pattern after all...

[Dan Beam, 2014/07/19 02:28:39]

Done.

+    "--jscomp_error=checkStructDictInheritance",
+    "--jscomp_error=checkTypes",
+    "--jscomp_error=checkVars",
+    "--jscomp_error=constantProperty",
+    "--jscomp_error=deprecated",
+    "--jscomp_error=duplicateMessage",

[arv (Not doing code reviews), 2014/07/16 18:33:02]

We do not use the MSG system

[Dan Beam, 2014/07/19 02:28:39]

Done.

+    "--jscomp_error=es3",

[arv (Not doing code reviews), 2014/07/16 18:33:02]

?

[Dan Beam, 2014/07/19 02:28:39]

Done.

+    "--jscomp_error=externsValidation",
+    "--jscomp_error=globalThis",
+    "--jscomp_error=invalidCasts",
+    "--jscomp_error=misplacedTypeAnnotation",
+    "--jscomp_error=missingProperties",
+    "--jscomp_error=missingReturn",
+    "--jscomp_error=nonStandardJsDocs",
+    "--jscomp_error=suspiciousCode",
+    "--jscomp_error=undefinedNames",
+    "--jscomp_error=undefinedVars",
+    "--jscomp_error=unknownDefines",
+    "--jscomp_error=uselessCode",
+    "--jscomp_error=visibility",
+  ]
+
+  _found_java = False
+
+  _jar_command = [
+    "java",
+    "-jar",
+    "-Xms1024m",
+    "-server",
+    "-XX:+TieredCompilation"
+  ]
+
+  def __init__(self, verbose=False):
+    self._current_dir = os.path.dirname(__file__)
+    self._compiler_jar = os.path.join(self._current_dir, "lib", "compiler.jar")
+    self._runner_jar = os.path.join(self._current_dir, "runner", "runner.jar")
+    self._temp_files = []
+    self._verbose = verbose
+
+  def _clean_up(self):
+    if not self._temp_files:
+      return
+
+    self._debug("Deleting temporary files: " + ", ".join(self._temp_files))
+    for f in self._temp_files:
+      os.remove(f)
+    self._temp_files = []
+
+  def _debug(self, msg, error=False):
+    if self._verbose:
+      print "(INFO) " + msg
+
+  def _fatal(self, msg):
+    print >> sys.stderr, "(FATAL) " + msg
+    self._clean_up()
+    sys.exit(1)
+
+  def _run_command(self, cmd):
+    cmd_str = " ".join(cmd)
+    self._debug("Running command: " + cmd_str)
+
+    devnull = open(os.devnull, "w")
+    return subprocess.Popen(
+        cmd_str, stdout=devnull, stderr=subprocess.PIPE, shell=True)
+
+  def _check_java_path(self):
+    if self._found_java:
+      return
+
+    proc = self._run_command(["which", "java"])
+    proc.communicate()
+    if proc.returncode == 0:
+      self._found_java = True
+    else:
+      self._fatal("Cannot find java (`which java` => %s)" % proc.returncode)
+
+  def _run_jar(self, jar, args=[]):
+    self._check_java_path()
+    return self._run_command(self._jar_command + [jar] + args)
+
+  def _real_line_number_from_temp_line(self, line_number):
+    line_number = int(line_number)
+
+    total = 0
+    for d in self._dep_lines:
+      if line_number <= total + d.line_count:
+        return LineNumber(d.file, line_number - total)
+      total += d.line_count
+
+    assert line_number <= total + self._line_info.line_count
+    return LineNumber(self._line_info.file, line_number - total)
+
+  def _fix_line_number(self, match):
+    real_file = self._real_line_number_from_temp_line(match.group(1))
+    return "%s:%d" % (real_file.file, real_file.line_number)
+
+  def _fix_up_error(self, error):
+    if " first declared in " in error:
+      # Ignore "Variable x first declared in /same/file".
+      return ""
+
+    file = self._line_info.file
+    line_number = re.search(":(\d+)", error).group(1)
+    if file != self._real_line_number_from_temp_line(line_number).file:
+      # Ignore errors in dependent files.
+      return ""
+   
+    source_file = self._temp_files[0]
+    lines_fixed = re.sub("%s:(\d+)" % source_file, self._fix_line_number, error)
+    return lines_fixed.replace(source_file, file)
+
+  def _external_script_output(self, output):
+    contents = (os.linesep + "## ").join("\n".join(output).splitlines())
+    return "## " + contents if contents else ""
+
+  def check(self, file, depends=[], externs=[]):
+    self._debug("FILE: " + file)
+
+    if file.endswith("_externs.js"):
+      self._debug("Skipping externs")
+      return
+
+    temp_file = tempfile.NamedTemporaryFile(mode='wt', delete=False)
+    self._temp_files.append(temp_file.name)
+
+    self._dep_lines = []
+
+    for d in depends:
+      dep_contents = open(d, "r").read()
+      self._dep_lines.append(LineCount(d, len(dep_contents.splitlines())))
+      temp_file.write(dep_contents)
+
+    file_contents = open(file, "r").read()
+    self._line_info = LineCount(file, len(file_contents.splitlines()))
+    temp_file.write(file_contents)
+
+    temp_file.close()
+
+    args = ["--js=" + temp_file.name] + ["--externs=" + e for e in externs]
+    args_file_content = " " + " ".join(self._common_closure_args + args)
+    self._debug("Args: " + args_file_content.strip())
+
+    args_file = tempfile.NamedTemporaryFile(mode='wt', delete=False)
+    self._temp_files.append(args_file.name)
+
+    self._debug("Args file: " + args_file.name)
+    args_file.write(args_file_content)
+    args_file.close()
+
+    runner_args = ["--compiler-args-file=" + args_file.name]
+    runner_cmd = self._run_jar(self._runner_jar, args=runner_args)
+    (_, stderr) = runner_cmd.communicate()
+
+    errors = stderr.strip().split("\n\n")
+    self._debug("Summary: " + errors.pop())
+
+    output = self._external_script_output(map(self._fix_up_error, errors))
+    if runner_cmd.returncode:
+      self._fatal("Error in: " + file + (os.linesep + output if output else ""))
+    elif output:
+      self._debug("Output: " + output)
+   
+    self._clean_up()
+
+    return runner_cmd.returncode == 0