Add presubmit check and automatic update script for ExtensionPermission enum.

tools/strict_enum_value_checker/strict_enum_value_checker.py

Index: tools/strict_enum_value_checker/strict_enum_value_checker.py
diff --git a/extensions/browser/PRESUBMIT.py b/tools/strict_enum_value_checker/strict_enum_value_checker.py
similarity index 77%
copy from extensions/browser/PRESUBMIT.py
copy to tools/strict_enum_value_checker/strict_enum_value_checker.py
index 29a709b5c807ff63d08b90bba2efb5c61c888067..65c4a9ecbf1181e894f8d1821d4875fe0348e616 100644
--- a/extensions/browser/PRESUBMIT.py
+++ b/tools/strict_enum_value_checker/strict_enum_value_checker.py
@@ -2,42 +2,25 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-"""Chromium presubmit script for src/extensions/browser.
-
-See http://dev.chromium.org/developers/how-tos/depottools/presubmit-scripts
-for more details on the presubmit API built into gcl.
-"""
-
-def GetPreferredTryMasters(project, change):
-  return {
-    'tryserver.chromium': {
-      'linux_chromium_chromeos_rel': set(['defaulttests']),
-    }
-  }
-
-class HistogramValueChecker(object):
-  """Verify that changes to "extension_function_histogram_value.h" are valid.
-
-  See comments at the top of the "extension_function_histogram_value.h" file
-  for what are considered valid changes. There are situations where this script
-  gives false positive warnings, i.e. it warns even though the edit is
-  legitimate. Since the script warns using prompt warnings, the user can always
-  choose to continue. The main point is to attract the attention to all
-  (potentially or not) invalid edits.
+class StrictEnumValueChecker(object):
+  """Verify that changes to enums are valid.
+
+  This class is used to check enums where reordering or deletion is not allowed,
+  and additions must be at the end of the enum, just prior to some "boundary"
+  entry. See comments at the top of the "extension_function_histogram_value.h"
+  file in chrome/browser/extensions for an example what are considered valid
+  changes. There are situations where this class gives false positive warnings,
+  i.e. it warns even though the edit is legitimate. Since the class warns using
+  prompt warnings, the user can always choose to continue. The main point is to
+  attract the attention to all (potentially or not) invalid edits.
 
   """
-
-  # The name of the file we want to check against
-  LOCAL_PATH = "extensions/browser/extension_function_histogram_value.h"
-
-  # The markers we look for in the above source file as delimiters of the enum
-  # definition.
-  ENUM_START_MARKER = "enum HistogramValue {"
-  ENUM_END_MARKER = "  // Last entry:"
-
-  def __init__(self, input_api, output_api):
+  def __init__(self, input_api, output_api, start_marker, end_marker, path):
     self.input_api = input_api
     self.output_api = output_api
+    self.start_marker = start_marker
+    self.end_marker = end_marker
+    self.path = path
     self.results = []
 
   class EnumRange(object):
@@ -62,11 +45,11 @@ class HistogramValueChecker(object):
 
   def ComputeEnumRangeInContents(self, contents):
     """Returns an |EnumRange| object representing the line extent of the
-    HistogramValue enum members in |contents|. The line numbers are 1-based,
+    enum members in |contents|. The line numbers are 1-based,
     compatible with line numbers returned by AffectedFile.ChangeContents().
     |contents| is a list of strings reprenting the lines of a text file.
 
-    If either ENUM_START_MARKER or ENUM_END_MARKER cannot be found in
+    If either start_marker or end_marker cannot be found in
     |contents|, returns None and emits detailed warnings about the problem.
 
     """
@@ -74,43 +57,43 @@ class HistogramValueChecker(object):
     last_enum_line = 0
     line_num = 1  # Line numbers are 1-based
     for line in contents:
-      if line.startswith(self.ENUM_START_MARKER):
+      if line.startswith(self.start_marker):
         first_enum_line = line_num + 1
-      elif line.startswith(self.ENUM_END_MARKER):
+      elif line.startswith(self.end_marker):
         last_enum_line = line_num
       line_num += 1
 
     if first_enum_line == 0:
       self.EmitWarning("The presubmit script could not find the start of the "
                        "enum definition (\"%s\"). Did the enum definition "
-                       "change?" % self.ENUM_START_MARKER)
+                       "change?" % self.start_marker)
       return None
 
     if last_enum_line == 0:
       self.EmitWarning("The presubmit script could not find the end of the "
                        "enum definition (\"%s\"). Did the enum definition "
-                       "change?" % self.ENUM_END_MARKER)
+                       "change?" % self.end_marker)
       return None
 
     if first_enum_line >= last_enum_line:
       self.EmitWarning("The presubmit script located the start of the enum "
                        "definition (\"%s\" at line %d) *after* its end "
                        "(\"%s\" at line %d). Something is not quite right."
-                       % (self.ENUM_START_MARKER, first_enum_line,
-                          self.ENUM_END_MARKER, last_enum_line))
+                       % (self.start_marker, first_enum_line,
+                          self.end_marker, last_enum_line))
       return None
 
-    self.LogInfo("Line extent of |HistogramValue| enum definition: "
+    self.LogInfo("Line extent of (\"%s\") enum definition: "
                  "first_line=%d, last_line=%d."
-                 % (first_enum_line, last_enum_line))
+                 % (self.start_marker, first_enum_line, last_enum_line))
     return self.EnumRange(first_enum_line, last_enum_line)
 
   def ComputeEnumRangeInNewFile(self, affected_file):
     return self.ComputeEnumRangeInContents(affected_file.NewContents())
 
-  def GetLongMessage(self):
+  def GetLongMessage(self, local_path):
     return str("The file \"%s\" contains the definition of the "
-               "|HistogramValue| enum which should be edited in specific ways "
+               "(\"%s\") enum which should be edited in specific ways "
                "only - *** read the comments at the top of the header file ***"
                ". There are changes to the file that may be incorrect and "
                "warrant manual confirmation after review. Note that this "
@@ -118,7 +101,7 @@ class HistogramValueChecker(object):
                "types of invalid changes, especially when the diffs are "
                "complex. For example, an invalid deletion may be reported "
                "whereas the change contains a valid rename."
-               % self.LOCAL_PATH)
+               % local_path, self.start_marker)
 
   def EmitWarning(self, message, line_number=None, line_text=None):
     """Emits a presubmit prompt warning containing the short message
@@ -127,12 +110,12 @@ class HistogramValueChecker(object):
 
     """
     if line_number is not None and line_text is not None:
-      item = "%s(%d): %s" % (self.LOCAL_PATH, line_number, line_text)
+      item = "%s(%d): %s" % (self.path, line_number, line_text)
     elif line_number is not None:
-      item = "%s(%d)" % (self.LOCAL_PATH, line_number)
+      item = "%s(%d)" % (self.path, line_number)
     else:
-      item = self.LOCAL_PATH
-    long_message = self.GetLongMessage()
+      item = self.path
+    long_message = self.GetLongMessage(self.path)
     self.LogInfo(message)
     self.results.append(
       self.output_api.PresubmitPromptWarning(message, [item], long_message))
@@ -182,7 +165,7 @@ class HistogramValueChecker(object):
       self.EmitWarning("The file seems to be deleted in the changelist. If "
                        "your intent is to really delete the file, the code in "
                        "PRESUBMIT.py should be updated to remove the "
-                       "|HistogramValueChecker| class.");
+                       "|StrictEnumValueChecker| class.");
       return False
     return True
 
@@ -206,7 +189,7 @@ class HistogramValueChecker(object):
       # Parse the unified diff chunk optional section heading, which looks like
       # @@ -l,s +l,s @@ optional section heading
       m = self.input_api.re.match(
-        r'^@@ \-([0-9]+)\,([0-9]+) \+([0-9]+)\,([0-9]+) @@', line)
+        r"^@@ \-([0-9]+)\,([0-9]+) \+([0-9]+)\,([0-9]+) @@", line)
       if m:
         old_line_num = int(m.group(1))
         old_size = int(m.group(2))
@@ -217,9 +200,9 @@ class HistogramValueChecker(object):
         # new file
         deleting_lines = old_size > new_size
         continue
-      if not line.startswith('-'):
+      if not line.startswith("-"):
         line_num += 1
-      if deleting_lines and line.startswith('-') and not line.startswith('--'):
+      if deleting_lines and line.startswith("-") and not line.startswith("--"):
         results.append(line_num)
     return results
 
@@ -272,10 +255,10 @@ class HistogramValueChecker(object):
         self.EmitWarning("The change starting at line %d and ending at line "
                          "%d is *not* located *exactly* at the end of the "
                          "enum definition. Unless you are renaming an "
-                         "existing entry, this is not a valid changes, as new "
+                         "existing entry, this is not a valid change, as new "
                          "entries should *always* be added at the end of the "
-                         "enum definition, right before the 'ENUM_BOUNDARY' "
-                         "entry." % (line_start, line_end),
+                         "enum definition, right before the \"%s\" "
+                         "entry." % (line_start, line_end, self.end_marker),
                          line_start,
                          line_text)
         is_ok = False
@@ -296,13 +279,6 @@ class HistogramValueChecker(object):
 
   def Run(self):
     for file in self.input_api.AffectedFiles(include_deletes=True):
-      if file.LocalPath() == self.LOCAL_PATH:
+      if file.LocalPath() == self.path:
         self.ProcessHistogramValueFile(file)
     return self.results
-
-def CheckChangeOnUpload(input_api, output_api):
-  results = []
-  results += HistogramValueChecker(input_api, output_api).Run()
-  results += input_api.canned_checks.CheckPatchFormatted(input_api, output_api)
-  return results
-