Archive svndiff script.

tools/svndiff.py

-#!/usr/bin/python
-'''
-Copyright 2012 Google Inc.
-
-Use of this source code is governed by a BSD-style license that can be
-found in the LICENSE file.
-'''
-
-'''
-Generates a visual diff of all pending changes in the local SVN (or git!)
-checkout.
-
-Launch with --help to see more information.
-
-TODO(epoger): Now that this tool supports either git or svn, rename it.
-TODO(epoger): Fix indentation in this file (2-space indents, not 4-space).
-'''
-
-# common Python modules
-import optparse
-import os
-import posixpath
-import re
-import shutil
-import subprocess
-import sys
-import tempfile
-import urllib2
-
-# Imports from within Skia
-#
-# We need to add the 'gm' directory, so that we can import gm_json.py within
-# that directory.  That script allows us to parse the actual-results.json file
-# written out by the GM tool.
-# Make sure that the 'gm' dir is in the PYTHONPATH, but add it at the *end*
-# so any dirs that are already in the PYTHONPATH will be preferred.
-#
-# This assumes that the 'gm' directory has been checked out as a sibling of
-# the 'tools' directory containing this script, which will be the case if
-# 'trunk' was checked out as a single unit.
-GM_DIRECTORY = os.path.realpath(
-    os.path.join(os.path.dirname(os.path.dirname(__file__)), 'gm'))
-if GM_DIRECTORY not in sys.path:
-    sys.path.append(GM_DIRECTORY)
-import gm_json
-import jsondiff
-import svn
-
-CHECKOUT_ROOT = os.path.realpath(
-    os.path.join(os.path.dirname(__file__), os.pardir))
-sys.path.append(CHECKOUT_ROOT)
-from common.py.utils import git_utils
-
-USAGE_STRING = 'Usage: %s [options]'
-HELP_STRING = '''
-
-Generates a visual diff of all pending changes in the local SVN/git checkout.
-
-This includes a list of all files that have been added, deleted, or modified
-(as far as SVN/git knows about).  For any image modifications, pixel diffs will
-be generated.
-
-'''
-
-IMAGE_FILENAME_RE = re.compile(gm_json.IMAGE_FILENAME_PATTERN)
-
-TRUNK_PATH = os.path.join(os.path.dirname(__file__), os.pardir)
-
-OPTION_DEST_DIR = '--dest-dir'
-OPTION_PATH_TO_SKDIFF = '--path-to-skdiff'
-OPTION_SOURCE_DIR = '--source-dir'
-
-def RunCommand(command):
-    """Run a command, raising an exception if it fails.
-
-    @param command the command as a single string
-    """
-    print 'running command [%s]...' % command
-    retval = os.system(command)
-    if retval is not 0:
-        raise Exception('command [%s] failed' % command)
-
-def FindPathToSkDiff(user_set_path=None):
-    """Return path to an existing skdiff binary, or raise an exception if we
-    cannot find one.
-
-    @param user_set_path if None, the user did not specify a path, so look in
-           some likely places; otherwise, only check at this path
-    """
-    if user_set_path is not None:
-        if os.path.isfile(user_set_path):
-            return user_set_path
-        raise Exception('unable to find skdiff at user-set path %s' %
-                        user_set_path)
-    trunk_path = os.path.join(os.path.dirname(__file__), os.pardir)
-
-    extension = ''
-    if os.name is 'nt':
-        extension = '.exe'
-        
-    possible_paths = [os.path.join(trunk_path, 'out', 'Release',
-                                    'skdiff' + extension),
-                      os.path.join(trunk_path, 'out', 'Debug',
-                                   'skdiff' + extension)]
-    for try_path in possible_paths:
-        if os.path.isfile(try_path):
-            return try_path
-    raise Exception('cannot find skdiff in paths %s; maybe you need to '
-                    'specify the %s option or build skdiff?' % (
-                        possible_paths, OPTION_PATH_TO_SKDIFF))
-
-def _DownloadUrlToFile(source_url, dest_path):
-    """Download source_url, and save its contents to dest_path.
-    Raises an exception if there were any problems."""
-    try:
-        reader = urllib2.urlopen(source_url)
-        writer = open(dest_path, 'wb')
-        writer.write(reader.read())
-        writer.close()
-    except BaseException as e:
-        raise Exception(
-            '%s: unable to download source_url %s to dest_path %s' % (
-                e, source_url, dest_path))
-
-def _CreateGSUrl(imagename, hash_type, hash_digest):
-    """Return the HTTP URL we can use to download this particular version of
-    the actually-generated GM image with this imagename.
-
-    imagename: name of the test image, e.g. 'perlinnoise_msaa4.png'
-    hash_type: string indicating the hash type used to generate hash_digest,
-               e.g. gm_json.JSONKEY_HASHTYPE_BITMAP_64BITMD5
-    hash_digest: the hash digest of the image to retrieve
-    """
-    return gm_json.CreateGmActualUrl(
-        test_name=IMAGE_FILENAME_RE.match(imagename).group(1),
-        hash_type=hash_type,
-        hash_digest=hash_digest)
-
-def _CallJsonDiff(old_json_path, new_json_path,
-                  old_flattened_dir, new_flattened_dir,
-                  filename_prefix):
-    """Using jsondiff.py, write the images that differ between two GM
-    expectations summary files (old and new) into old_flattened_dir and
-    new_flattened_dir.
-
-    filename_prefix: prefix to prepend to filenames of all images we write
-        into the flattened directories
-    """
-    json_differ = jsondiff.GMDiffer()
-    diff_dict = json_differ.GenerateDiffDict(oldfile=old_json_path,
-                                             newfile=new_json_path)
-    print 'Downloading %d before-and-after image pairs...' % len(diff_dict)
-    for (imagename, results) in diff_dict.iteritems():
-        # TODO(epoger): Currently, this assumes that all images have been
-        # checksummed using gm_json.JSONKEY_HASHTYPE_BITMAP_64BITMD5
-
-        old_checksum = results['old']
-        if old_checksum:
-            old_image_url = _CreateGSUrl(
-                imagename=imagename,
-                hash_type=gm_json.JSONKEY_HASHTYPE_BITMAP_64BITMD5,
-                hash_digest=old_checksum)
-            _DownloadUrlToFile(
-                source_url=old_image_url,
-                dest_path=os.path.join(old_flattened_dir,
-                                       filename_prefix + imagename))
-
-        new_checksum = results['new']
-        if new_checksum:
-            new_image_url = _CreateGSUrl(
-                imagename=imagename,
-                hash_type=gm_json.JSONKEY_HASHTYPE_BITMAP_64BITMD5,
-                hash_digest=new_checksum)
-            _DownloadUrlToFile(
-                source_url=new_image_url,
-                dest_path=os.path.join(new_flattened_dir,
-                                       filename_prefix + imagename))
-
-def _RunCommand(args):
-    """Run a command (from self._directory) and return stdout as a single
-    string.
-
-    @param args a list of arguments
-    """
-    proc = subprocess.Popen(args,
-                            stdout=subprocess.PIPE,
-                            stderr=subprocess.PIPE)
-    (stdout, stderr) = proc.communicate()
-    if proc.returncode is not 0:
-        raise Exception('command "%s" failed: %s' % (args, stderr))
-    return stdout
-
-
-def _GitExportBaseVersionOfFile(file_within_repo, dest_path):
-    """Retrieves a copy of the base version of a file within the repository.
-
-    @param file_within_repo path to the file within the repo whose base
-           version you wish to obtain
-    @param dest_path destination to which to write the base content
-
-    TODO(epoger): Move this into a git utility package?
-    """
-    # TODO(epoger): Replace use of "git show" command with lower-level git
-    # commands?  senorblanco points out that "git show" is a "porcelain"
-    # command, intended for human use, as opposed to the "plumbing" commands
-    # generally more suitable for scripting.  (See
-    # http://git-scm.com/book/en/Git-Internals-Plumbing-and-Porcelain )
-    #
-    # For now, though, "git show" is the most straightforward implementation
-    # I could come up with.  I tried using "git cat-file", but I had trouble
-    # getting it to work as desired.
-    # Note that git expects / rather than \ as a path separator even on
-    # windows.
-    args = ['git', 'show', posixpath.join('HEAD:.', file_within_repo)]
-    with open(dest_path, 'wb') as outfile:
-        proc = subprocess.Popen(args, stdout=outfile)
-        proc.communicate()
-        if proc.returncode is not 0:
-            raise Exception('command "%s" failed' % args)
-
-def SvnDiff(path_to_skdiff, dest_dir, source_dir):
-    """Generates a visual diff of all pending changes in source_dir.
-
-    @param path_to_skdiff
-    @param dest_dir existing directory within which to write results
-    @param source_dir
-    """
-    # Validate parameters, filling in default values if necessary and possible.
-    path_to_skdiff = os.path.abspath(FindPathToSkDiff(path_to_skdiff))
-    if not dest_dir:
-        dest_dir = tempfile.mkdtemp()
-    dest_dir = os.path.abspath(dest_dir)
-
-    os.chdir(source_dir)
-    svn_repo = svn.Svn('.')
-    using_svn = True
-    try:
-      svn_repo.GetInfo()
-    except:
-      using_svn = False
-
-    # Prepare temporary directories.
-    modified_flattened_dir = os.path.join(dest_dir, 'modified_flattened')
-    original_flattened_dir = os.path.join(dest_dir, 'original_flattened')
-    diff_dir = os.path.join(dest_dir, 'diffs')
-    for dir in [modified_flattened_dir, original_flattened_dir, diff_dir] :
-        shutil.rmtree(dir, ignore_errors=True)
-        os.mkdir(dir)
-
-    # Get a list of all locally modified (including added/deleted) files,
-    # descending subdirectories.
-    if using_svn:
-        modified_file_paths = svn_repo.GetFilesWithStatus(
-            svn.STATUS_ADDED | svn.STATUS_DELETED | svn.STATUS_MODIFIED)
-    else:
-        modified_file_paths = git_utils.GetModifiedFiles()
-
-    # For each modified file:
-    # 1. copy its current contents into modified_flattened_dir
-    # 2. copy its original contents into original_flattened_dir
-    for modified_file_path in modified_file_paths:
-        if modified_file_path.endswith('.json'):
-            # Special handling for JSON files, in the hopes that they
-            # contain GM result summaries.
-            original_file = tempfile.NamedTemporaryFile(delete = False)
-            original_file.close()
-            if using_svn:
-                svn_repo.ExportBaseVersionOfFile(
-                    modified_file_path, original_file.name)
-            else:
-                _GitExportBaseVersionOfFile(
-                    modified_file_path, original_file.name)
-            modified_dir = os.path.dirname(modified_file_path)
-            platform_prefix = (re.sub(re.escape(os.sep), '__',
-                                      os.path.splitdrive(modified_dir)[1])
-                              + '__')
-            _CallJsonDiff(old_json_path=original_file.name,
-                          new_json_path=modified_file_path,
-                          old_flattened_dir=original_flattened_dir,
-                          new_flattened_dir=modified_flattened_dir,
-                          filename_prefix=platform_prefix)
-            os.remove(original_file.name)
-        else:
-            dest_filename = re.sub(re.escape(os.sep), '__', modified_file_path)
-            # If the file had STATUS_DELETED, it won't exist anymore...
-            if os.path.isfile(modified_file_path):
-                shutil.copyfile(modified_file_path,
-                                os.path.join(modified_flattened_dir,
-                                             dest_filename))
-            if using_svn:
-                svn_repo.ExportBaseVersionOfFile(
-                    modified_file_path,
-                    os.path.join(original_flattened_dir, dest_filename))
-            else:
-                _GitExportBaseVersionOfFile(
-                    modified_file_path,
-                    os.path.join(original_flattened_dir, dest_filename))
-
-    # Run skdiff: compare original_flattened_dir against modified_flattened_dir
-    RunCommand('%s %s %s %s' % (path_to_skdiff, original_flattened_dir,
-                                modified_flattened_dir, diff_dir))
-    print '\nskdiff results are ready in file://%s/index.html' % diff_dir
-
-def RaiseUsageException():
-    raise Exception('%s\nRun with --help for more detail.' % (
-        USAGE_STRING % __file__))
-
-def Main(options, args):
-    """Allow other scripts to call this script with fake command-line args.
-    """
-    num_args = len(args)
-    if num_args != 0:
-        RaiseUsageException()
-    SvnDiff(path_to_skdiff=options.path_to_skdiff, dest_dir=options.dest_dir,
-            source_dir=options.source_dir)
-
-if __name__ == '__main__':
-    parser = optparse.OptionParser(USAGE_STRING % '%prog' + HELP_STRING)
-    parser.add_option(OPTION_DEST_DIR,
-                      action='store', type='string', default=None,
-                      help='existing directory within which to write results; '
-                      'if not set, will create a temporary directory which '
-                      'will remain in place after this script completes')
-    parser.add_option(OPTION_PATH_TO_SKDIFF,
-                      action='store', type='string', default=None,
-                      help='path to already-built skdiff tool; if not set, '
-                      'will search for it in typical directories near this '
-                      'script')
-    parser.add_option(OPTION_SOURCE_DIR,
-                      action='store', type='string',
-                      default=os.path.join('expectations', 'gm'),
-                      help='root directory within which to compare all ' +
-                      'files; defaults to "%default"')
-    (options, args) = parser.parse_args()
-    Main(options, args)