pixelmatch

A single executable pixelmatch for Swift Package Manager. Works greate with swift-snapshot-testing.

Installation

Swift Package Manager

dependencies: [
  // ...
  .package(url: "https://github.com/ramble-inc/pixelmatch", from: "5.2.1"),
],

cURL

curl -sS -o pixelmatch -L https://github.com/ramble-inc/pixelmatch/releases/download/5.2.1/pixelmatch

Usage

Same as pixelmatch

pixelmatch image1.png image2.png output.png 0.1

Sample script to generate diff images for swift-snapshot-testing.

#!/bin/sh

GREEN='\033[0;32m'
BLUE='\033[0;34m'
RED='\033[0;31m'
RESET='\033[0m'
SNAPSHOT_ROOT=MyAppSnapshotTests
SNAPSHOT_DIR=$SNAPSHOT_ROOT/__Snapshots__
SNAPSHOT_FAILURE_DIR=$SNAPSHOT_ROOT/__Snapshots_Failure__
SNAPSHOT_DIFF_DIR=$SNAPSHOT_ROOT/__Snapshots_Diff__
THRESHOLD=0.1

if [ ! -d $SNAPSHOT_FAILURE_DIR ]; then
  echo "$SNAPSHOT_FAILURE_DIR does not exist. Skip generating diff images."
  exit 0
fi

rm -rf $SNAPSHOT_DIFF_DIR

for dir in $(ls -d $SNAPSHOT_DIR/*/); do
  TEST_CASE=$(basename $dir)
  mkdir -p $SNAPSHOT_DIFF_DIR/$TEST_CASE

  for file in $(ls $SNAPSHOT_DIR/$TEST_CASE/*.png); do
    IMAGE=$(basename $file)
    echo "${BLUE}$TEST_CASE/$IMAGE${RESET}"

    swift run pixelmatch \
      $SNAPSHOT_DIR/$TEST_CASE/$IMAGE \
      $SNAPSHOT_FAILURE_DIR/$TEST_CASE/$IMAGE \
      $SNAPSHOT_DIFF_DIR/$TEST_CASE/$IMAGE \
      $THRESHOLD

    echo
  done
done

echo "${GREEN}✔${RESET} done"

Disclaimer

The executable is about 70MB because pixelmatch is packaged into a single executable with pkg.