Change ServiceManager::SetLoaderForUrl() to SetLoaderForScheme()
[chromium-blink-merge.git] / media / PRESUBMIT.py
blob279115ccb2fd596e6f50efb053fa1653cc442cce
1 # Copyright 2013 The Chromium Authors. All rights reserved.
2 # Use of this source code is governed by a BSD-style license that can be
3 # found in the LICENSE file.
5 """Top-level presubmit script for Chromium media component.
7 See http://dev.chromium.org/developers/how-tos/depottools/presubmit-scripts
8 for more details about the presubmit API built into gcl.
9 """
11 def _FilterFile(affected_file):
12 """Return true if the file could contain code requiring a presubmit check."""
13 return affected_file.LocalPath().endswith(
14 ('.h', '.cc', '.cpp', '.cxx', '.mm'))
17 def _CheckForUseOfWrongClock(input_api, output_api):
18 """Make sure new lines of media code don't use a clock susceptible to skew."""
20 # Regular expression that should detect any explicit references to the
21 # base::Time type (or base::Clock/DefaultClock), whether in using decls,
22 # typedefs, or to call static methods.
23 base_time_type_pattern = r'(^|\W)base::(Time|Clock|DefaultClock)(\W|$)'
25 # Regular expression that should detect references to the base::Time class
26 # members, such as a call to base::Time::Now.
27 base_time_member_pattern = r'(^|\W)(Time|Clock|DefaultClock)::'
29 # Regular expression to detect "using base::Time" declarations. We want to
30 # prevent these from triggerring a warning. For example, it's perfectly
31 # reasonable for code to be written like this:
33 # using base::Time;
34 # ...
35 # int64 foo_us = foo_s * Time::kMicrosecondsPerSecond;
36 using_base_time_decl_pattern = r'^\s*using\s+(::)?base::Time\s*;'
38 # Regular expression to detect references to the kXXX constants in the
39 # base::Time class. We want to prevent these from triggerring a warning.
40 base_time_konstant_pattern = r'(^|\W)Time::k\w+'
42 problem_re = input_api.re.compile(
43 r'(' + base_time_type_pattern + r')|(' + base_time_member_pattern + r')')
44 exception_re = input_api.re.compile(
45 r'(' + using_base_time_decl_pattern + r')|(' +
46 base_time_konstant_pattern + r')')
47 problems = []
48 for f in input_api.AffectedSourceFiles(_FilterFile):
49 for line_number, line in f.ChangedContents():
50 if problem_re.search(line):
51 if not exception_re.search(line):
52 problems.append(
53 ' %s:%d\n %s' % (f.LocalPath(), line_number, line.strip()))
55 if problems:
56 return [output_api.PresubmitPromptOrNotify(
57 'You added one or more references to the base::Time class and/or one\n'
58 'of its member functions (or base::Clock/DefaultClock). In media\n'
59 'code, it is rarely correct to use a clock susceptible to time skew!\n'
60 'Instead, could you use base::TimeTicks to track the passage of\n'
61 'real-world time?\n\n' +
62 '\n'.join(problems))]
63 else:
64 return []
67 def _CheckForMessageLoopProxy(input_api, output_api):
68 """Make sure media code only uses MessageLoopProxy for accessing the current
69 loop."""
71 message_loop_proxy_re = input_api.re.compile(
72 r'\bMessageLoopProxy(?!::current\(\))')
74 problems = []
75 for f in input_api.AffectedSourceFiles(_FilterFile):
76 for line_number, line in f.ChangedContents():
77 if message_loop_proxy_re.search(line):
78 problems.append('%s:%d' % (f.LocalPath(), line_number))
80 if problems:
81 return [output_api.PresubmitError(
82 'MessageLoopProxy should only be used for accessing the current loop.\n'
83 'Use the TaskRunner interfaces instead as they are more explicit about\n'
84 'the run-time characteristics. In most cases, SingleThreadTaskRunner\n'
85 'is a drop-in replacement for MessageLoopProxy.', problems)]
87 return []
90 def _CheckForHistogramOffByOne(input_api, output_api):
91 """Make sure histogram enum maxes are used properly"""
93 # A general-purpose chunk of regex to match whitespace and/or comments
94 # that may be interspersed with the code we're interested in:
95 comment = r'/\*.*?\*/|//[^\n]*'
96 whitespace = r'(?:[\n\t ]|(?:' + comment + r'))*'
98 # The name is assumed to be a literal string.
99 histogram_name = r'"[^"]*"'
101 # This can be an arbitrary expression, so just ensure it isn't a ; to prevent
102 # matching past the end of this statement.
103 histogram_value = r'[^;]*'
105 # In parens so we can retrieve it for further checks.
106 histogram_max = r'([^;,]*)'
108 # This should match a uma histogram enumeration macro expression.
109 uma_macro_re = input_api.re.compile(
110 r'\bUMA_HISTOGRAM_ENUMERATION\(' + whitespace + histogram_name + r',' +
111 whitespace + histogram_value + r',' + whitespace + histogram_max +
112 whitespace + r'\)' + whitespace + r';(?:' + whitespace +
113 r'\/\/ (PRESUBMIT_IGNORE_UMA_MAX))?')
115 uma_max_re = input_api.re.compile(r'.*(?:Max|MAX).* \+ 1')
117 problems = []
119 for f in input_api.AffectedSourceFiles(_FilterFile):
120 contents = input_api.ReadFile(f)
122 # We want to match across lines, but still report a line number, so we keep
123 # track of the line we're on as we search through the file.
124 line_number = 1
126 # We search the entire file, then check if any violations are in the changed
127 # areas, this is inefficient, but simple. A UMA_HISTOGRAM_ENUMERATION call
128 # will often span multiple lines, so finding a match looking just at the
129 # deltas line-by-line won't catch problems.
130 match = uma_macro_re.search(contents)
131 while match:
132 line_number += contents.count('\n', 0, match.start())
133 max_arg = match.group(1) # The third argument.
135 if (not uma_max_re.match(max_arg) and match.group(2) !=
136 'PRESUBMIT_IGNORE_UMA_MAX'):
137 uma_range = range(match.start(), match.end() + 1)
138 # Check if any part of the match is in the changed lines:
139 for num, line in f.ChangedContents():
140 if line_number <= num <= line_number + match.group().count('\n'):
141 problems.append('%s:%d' % (f, line_number))
142 break
144 # Strip off the file contents up to the end of the match and update the
145 # line number.
146 contents = contents[match.end():]
147 line_number += match.group().count('\n')
148 match = uma_macro_re.search(contents)
150 if problems:
151 return [output_api.PresubmitError(
152 'UMA_HISTOGRAM_ENUMERATION reports in src/media/ are expected to adhere\n'
153 'to the following guidelines:\n'
154 ' - The max value (3rd argument) should be an enum value equal to the\n'
155 ' last valid value, e.g. FOO_MAX = LAST_VALID_FOO.\n'
156 ' - 1 must be added to that max value.\n'
157 'Contact rileya@chromium.org if you have questions.' , problems)]
159 return []
162 def _CheckChange(input_api, output_api):
163 results = []
164 results.extend(_CheckForUseOfWrongClock(input_api, output_api))
165 results.extend(_CheckForMessageLoopProxy(input_api, output_api))
166 results.extend(_CheckForHistogramOffByOne(input_api, output_api))
167 return results
170 def CheckChangeOnUpload(input_api, output_api):
171 return _CheckChange(input_api, output_api)
174 def CheckChangeOnCommit(input_api, output_api):
175 return _CheckChange(input_api, output_api)