pdf comparison tool

tools/pdf-comparison.sh

Index: tools/pdf-comparison.sh
diff --git a/tools/pdf-comparison.sh b/tools/pdf-comparison.sh
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+#!/bin/sh
+
+# Copyright 2016 Google Inc.
+#
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# This tool compares the PDF output of Skia's DM tool of two commits.
+
+CONTROL_COMMIT="$1"
+EXPERIMENT_COMMIT="$2"
+
+SOURCE="${3:-gm}" # could be 'skp'
+
+if ! [ "$1" ] || ! [ "$2" ]; then
+    echo "usage:" >&2
+    echo "  $0 CONTROL_COMMIT EXPERIMENT_COMMIT [SOURCE]" >&2
+    exit 1
+fi
+
+BAD=''
+for CMD in 'python' 'ninja' 'pdfium_test' 'timeout' 'skdiff'; do
+    if ! command -v "$CMD" > /dev/null ; then
+        echo "could not find $CMD command in PATH." >&2
+        BAD=1
+    fi
+done
+if [ "$BAD" ]; then exit 1; fi
+
+cd "$(dirname "$0")/.."
+if [ "$(git diff --shortstat)" ]; then
+    echo "please stash your changes" >&2
+    exit 1
+fi
+
+DIR=$(mktemp -d "${TMPDIR:-/tmp}/skpdf.XXXXXXXXXX")
+EXP="${DIR}/exp"
+CON="${DIR}/con"
+
+set -e
+
+git checkout "$EXPERIMENT_COMMIT"
+python bin/sync-and-gyp && ninja -C out/Release dm
+out/Release/dm --src "$SOURCE" --config pdf -w "$EXP"
+
+git checkout "$CONTROL_COMMIT"
+python bin/sync-and-gyp && ninja -C out/Release dm
+out/Release/dm --src "$SOURCE" --config pdf -w "$CON"
+
+set +e
+
+EXP_DIR="${EXP}/pdf/${SOURCE}"
+CON_DIR="${CON}/pdf/${SOURCE}"
+
+DIFFS=''
+# remove byte-identical PDFs
+for con in "$CON_DIR"/*pdf; do
+    exp="$EXP_DIR/$(basename "$con")"
+    if diff "$con" "$exp" > /dev/null; then
+        rm "$con" "$exp" # no difference
+    else
+        echo "PDF differs: $(basename "$con")"
+        DIFFS=1
+    fi
+done
+if [ -z "$DIFFS" ]; then
+    echo 'All PDFs are byte-identical!'
+    rm -r "$DIR"
+    exit 0;
+fi
+
+# rasterize the remaining PDFs
+for pdf in "$CON_DIR"/*pdf "$EXP_DIR"/*pdf ; do
+    # timeout is from GNU coreutils
+    if timeout 10 pdfium_test --png "$pdf"; then
+        rm "$pdf"
+    else
+        echo "pdfium_test '$pdf' failed."
+    fi
+done
+
+DIFFS=''
+# remove byte-identical PNGs:
+for con in "$CON_DIR"/*.png; do
+    exp="$EXP_DIR/$(basename "$con")"
+    if diff "$con" "$exp"; then
+        rm "$exp" "$con"
+    else
+        echo "PNG differs: $(basename "$con")"
+        DIFFS=1
+    fi
+done
+if [ -z "$DIFFS" ]; then
+    echo 'All PNGs are byte-identical!'
+    rm -r "$DIR"
+    exit 0;
+fi
+
+# run remaining PNG files through skdiff:
+DIFF_DIR="${DIR}/skdiffout"
+skdiff "$CON_DIR" "$EXP_DIR"  "$DIFF_DIR"
+echo "'$DIFF_DIR/index.html'"
+
+if [ $(uname) = 'Darwin' ] ; then
+    open "$DIFF_DIR/index.html"  # look at diffs
+elif [ $(uname) = 'Linux' ] ; then
+    xdg-open "$DIFF_DIR/index.html"  # look at diffs
+fi