# Copyright 2012 The Chromium Authors
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
"""Presubmit script for Chromium browser resources.
See http://dev.chromium.org/developers/how-tos/depottools/presubmit-scripts
for more details about the presubmit API built into depot_tools, and see
https://chromium.googlesource.com/chromium/src/+/main/styleguide/web/web.md
for the rules we're checking against here.
"""
import os
import struct
class InvalidPNGException(Exception):
pass
class ResourceScaleFactors(object):
"""Verifier of image dimensions for Chromium resources.
This class verifies the image dimensions of resources in the various
resource subdirectories.
Attributes:
paths: An array of tuples giving the folders to check and their
relevant scale factors. For example:
[(100, 'default_100_percent'), (200, 'default_200_percent')]
"""
def __init__(self, input_api, output_api, paths):
""" Initializes ResourceScaleFactors with paths."""
self.input_api = input_api
self.output_api = output_api
self.paths = paths
def RunChecks(self):
"""Verifies the scale factors of resources being added or modified.
Returns:
An array of presubmit errors if any images were detected not
having the correct dimensions.
"""
def ImageSize(filename):
with open(filename, 'rb', buffering=0) as f:
data = f.read(24)
if data[:8] != b'\x89PNG\r\n\x1A\n' or data[12:16] != b'IHDR':
raise InvalidPNGException
return struct.unpack('>ii', data[16:24])
# Returns a list of valid scaled image sizes. The valid sizes are the
# floor and ceiling of (base_size * scale_percent / 100). This is equivalent
# to requiring that the actual scaled size is less than one pixel away from
# the exact scaled size.
def ValidSizes(base_size, scale_percent):
return sorted(set([(base_size * scale_percent) / 100,
(base_size * scale_percent + 99) / 100]))
repository_path = self.input_api.os_path.relpath(
self.input_api.PresubmitLocalPath(),
self.input_api.change.RepositoryRoot())
results = []
# Check for affected files in any of the paths specified.
affected_files = self.input_api.AffectedFiles(include_deletes=False)
files = []
for f in affected_files:
for path_spec in self.paths:
path_root = self.input_api.os_path.join(
repository_path, path_spec[1])
if (f.LocalPath().endswith('.png') and
f.LocalPath().startswith(path_root)):
# Only save the relative path from the resource directory.
relative_path = self.input_api.os_path.relpath(f.LocalPath(),
path_root)
if relative_path not in files:
files.append(relative_path)
corrupt_png_error = ('Corrupt PNG in file %s. Note that binaries are not '
'correctly uploaded to the code review tool and must be directly '
'submitted using the dcommit command.')
for f in files:
base_image = self.input_api.os_path.join(self.paths[0][1], f)
if not os.path.exists(base_image):
results.append(self.output_api.PresubmitError(
'Base image %s does not exist' % self.input_api.os_path.join(
repository_path, base_image)))
continue
try:
base_dimensions = ImageSize(base_image)
except InvalidPNGException:
results.append(self.output_api.PresubmitError(corrupt_png_error %
self.input_api.os_path.join(repository_path, base_image)))
continue
# Find all scaled versions of the base image and verify their sizes.
for i in range(1, len(self.paths)):
image_path = self.input_api.os_path.join(self.paths[i][1], f)
if not os.path.exists(image_path):
continue
# Ensure that each image for a particular scale factor is the
# correct scale of the base image.
try:
scaled_dimensions = ImageSize(image_path)
except InvalidPNGException:
results.append(self.output_api.PresubmitError(corrupt_png_error %
self.input_api.os_path.join(repository_path, image_path)))
continue
for dimension_name, base_size, scaled_size in zip(
('width', 'height'), base_dimensions, scaled_dimensions):
valid_sizes = ValidSizes(base_size, self.paths[i][0])
if scaled_size not in valid_sizes:
results.append(self.output_api.PresubmitError(
'Image %s has %s %d, expected to be %s' % (
self.input_api.os_path.join(repository_path, image_path),
dimension_name,
scaled_size,
' or '.join(map(str, valid_sizes)))))
return results