Create compare-baselines tool to compare locally generated and checked-in GMs.

Review URL: https://codereview.appspot.com/5616056

git-svn-id: http://skia.googlecode.com/svn/trunk@3128 2bbb7eff-a529-9590-31e7-b0007b416f81

tools/compare-baselines.py

@@ -0,0 +1,136 @@
+'''
+Compares the gm results within the local checkout against those already
+committed to the Skia repository. Relies on skdiff to do the low-level
+comparison.
+
+Sample usage to compare locally generated gm results against the
+checked-in ones:
+
+cd .../trunk
+make tools      # or otherwise get a runnable skdiff
+python tools/compare-baselines.py gm
+# validate that the new images look right
+
+Launch with --help to see more options.
+
+
+Copyright 2012 Google Inc.
+
+Use of this source code is governed by a BSD-style license that can be
+found in the LICENSE file.
+'''
+
+# common Python modules
+import fnmatch
+import optparse
+import os
+import shutil
+import tempfile
+
+# modules declared within this same directory
+import svn
+
+# Base URL of SVN repository where we store the checked-in gm results.
+SVN_GM_URL = 'http://skia.googlecode.com/svn/trunk/gm'
+
+USAGE_STRING = 'usage: %s [options] <gm basedir>'
+OPTION_PATH_TO_SKDIFF = '--path-to-skdiff'
+
+def CopyAllFilesAddingPrefix(source_dir, dest_dir, prefix):
+    """Copy all files from source_dir into dest_dir, adding prefix to the name
+    of each one as we copy it.
+    prefixes.
+
+    @param source_dir
+    @param dest_dir where to save the copied files
+    @param prefix prefix to add to each filename when we make the copy
+    """
+    all_filenames = os.listdir(source_dir)
+    for filename in all_filenames:
+        source_path = os.path.join(source_dir, filename)
+        if os.path.isdir(source_path):
+            print 'skipping %s because it is a directory, not a file' % filename
+            continue
+        dest_path = os.path.join(dest_dir, '%s%s' % (prefix, filename))
+        shutil.copyfile(source_path, dest_path)
+
+def Flatten(source_dir, dest_dir, subdirectory_pattern):
+    """Copy all files from matching subdirectories under source_dir into
+    dest_dir, flattened into a single directory using subdirectory names as
+    prefixes.
+
+    @param source_dir
+    @param dest_dir where to save the copied files
+    @param subdirectory_pattern only copy files from subdirectories that match
+           this Unix-style filename pattern (e.g., 'base-*')
+    """
+    all_filenames = os.listdir(source_dir)
+    matching_filenames = fnmatch.filter(all_filenames, subdirectory_pattern)
+    for filename in matching_filenames:
+        source_path = os.path.join(source_dir, filename)
+        if not os.path.isdir(source_path):
+            print 'skipping %s because it is a file, not a directory' % filename
+            continue
+        print 'flattening directory %s' % source_path
+        CopyAllFilesAddingPrefix(source_dir=source_path, dest_dir=dest_dir,
+                                 prefix='%s_' % filename)
+
+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 Main(options, args):
+    """Compare the gm results within the local checkout against those already
+    committed to the Skia repository.
+
+    @param options
+    @param args
+    """
+    num_args = len(args)
+    if num_args != 1:
+        RaiseUsageException()
+    gm_basedir = args[0].rstrip(os.sep)
+
+    tempdir_base = tempfile.mkdtemp()
+
+    # Download all checked-in baseline images to a temp directory
+    checkedin_dir = os.path.join(tempdir_base, 'checkedin')
+    os.mkdir(checkedin_dir)
+    svn.Svn(checkedin_dir).Checkout(SVN_GM_URL, '.')
+
+    # Flatten those checked-in baseline images into checkedin_flattened_dir
+    checkedin_flattened_dir = os.path.join(tempdir_base, 'checkedin_flattened')
+    os.mkdir(checkedin_flattened_dir)
+    Flatten(source_dir=checkedin_dir, dest_dir=checkedin_flattened_dir,
+            subdirectory_pattern='base-*')
+
+    # Flatten the local baseline images into local_flattened_dir
+    local_flattened_dir = os.path.join(tempdir_base, 'local_flattened')
+    os.mkdir(local_flattened_dir)
+    Flatten(source_dir=gm_basedir, dest_dir=local_flattened_dir,
+            subdirectory_pattern='base-*')
+
+    # Run skdiff to compare checkedin_flattened_dir against local_flattened_dir
+    diff_dir = os.path.join(tempdir_base, 'diffs')
+    os.mkdir(diff_dir)
+    RunCommand('%s %s %s %s' % (options.path_to_skdiff, checkedin_flattened_dir,
+                                local_flattened_dir, diff_dir))
+    print '\nskdiff results are ready in file://%s/index.html' % diff_dir
+
+def RaiseUsageException():
+    raise Exception(USAGE_STRING %  __file__)
+
+if __name__ == '__main__':
+    parser = optparse.OptionParser(USAGE_STRING % '%prog')
+    parser.add_option(OPTION_PATH_TO_SKDIFF,
+                      action='store', type='string',
+                      default=os.path.join('out', 'Debug', 'skdiff'),
+                      help='path to already-built skdiff tool')
+    (options, args) = parser.parse_args()
+    Main(options, args)

tools/download-baselines.py

@@ -9,8 +9,9 @@ cd .../trunk
 svn update
 # make sure there are no files awaiting svn commit
 python tools/download-baselines.py gm/base-macmini-lion-fixed  # or other gm/ subdir
+# validate that the new images look right (maybe using compare-baselines.py)
 # upload CL for review
-# validate that the new images look right
+# validate that the new images look right in the review tool
 # commit CL
 
 Launch with --help to see more options.