misc(i18n): add assertion script

.travis.yml

@@ -41,6 +41,7 @@ script:
   - yarn test-extension
   - yarn test-viewer
   - yarn test-lantern
+  - yarn i18n:checks
   # _JAVA_OPTIONS is breaking parsing of compiler output. See #3338.
   - unset _JAVA_OPTIONS
   # FIXME(paulirish): re-enable after a roll of LH->CDT

lighthouse-core/scripts/i18n/assert-strings-collected.sh

@@ -0,0 +1,50 @@
+#!/usr/bin/env bash
+
+##
+# @license Copyright 2018 Google Inc. All Rights Reserved.
+# Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
+# Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.
+##
+
+pwd="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
+lhroot_path="$pwd/../../.."
+lh_tmp_path="$lhroot_path/.tmp"
+mkdir -p "$lh_tmp_path"
+
+purple='\033[1;35m'
+red='\033[1;31m'
+green='\033[1;32m'
+colorText() {
+  printf "\\n$2$1%b\\n" '\033[0m'
+}
+
+collectedstringsPath="$lhroot_path/lighthouse-core/lib/locales/en-US.json";
+currentstringsPath="$lh_tmp_path/current_strings.json";
+freshstringsPath="$lh_tmp_path/fresh_strings.json";
+
+# always run this before exiting
+function teardown { rm -f "$currentstringsPath" "$freshstringsPath"; }
+trap teardown EXIT
+
+cp $collectedstringsPath $currentstringsPath
+
+colorText "Collecting strings..." "$purple"
+set -x
+node "$lhroot_path/lighthouse-core/scripts/i18n/collect-strings.js"
+set +x
+
+cp $collectedstringsPath $freshstringsPath
+
+colorText "Diff'ing golden strings against the fresh strings" "$purple"
+git --no-pager diff --color=always --no-index "$currentstringsPath" "$freshstringsPath"
+
+# Use the return value from last command
+retVal=$?
+
+if [ $retVal -eq 0 ]; then
+  colorText "✅  PASS. All strings have been collected." "$green"
+else
+  colorText "❌  FAIL. Strings have changed." "$red"
+  echo "Commit the changes to `lighthouse-core/lib/locales/` update the strings."
+fi
+exit $retVal

lighthouse-core/scripts/i18n/collect-strings.js

@@ -91,7 +91,7 @@ function writeStringsToLocaleFormat(locale, strings) {
     output[key] = {message};
   }
 
-  fs.writeFileSync(fullPath, JSON.stringify(output, null, 2));
+  fs.writeFileSync(fullPath, JSON.stringify(output, null, 2) + '\n');
 }
 
 const strings = collectAllStringsInDir(path.join(LH_ROOT, 'lighthouse-core'));

package.json

@@ -62,6 +62,8 @@
     "plots-smoke": "bash plots/test/smoke.sh",
     "changelog": "conventional-changelog --config ./build/changelog-generator/index.js --infile changelog.md --same-file",
     "type-check": "tsc -p . && cd ./lighthouse-viewer && yarn type-check",
+    "i18n:checks": "./lighthouse-core/scripts/i18n/assert-strings-collected.sh",
+    "i18n:collect-strings": "node lighthouse-core/scripts/i18n/collect-strings.js",
     "update:sample-artifacts": "node lighthouse-core/scripts/update-report-fixtures.js -G",
     "update:sample-json": "node ./lighthouse-cli -A=./lighthouse-core/test/results/artifacts --throttling-method=devtools --output=json --output-path=./lighthouse-core/test/results/sample_v2.json && node lighthouse-core/scripts/cleanup-LHR-for-diff.js ./lighthouse-core/test/results/sample_v2.json --only-remove-timing",
     "diff:sample-json": "bash lighthouse-core/scripts/assert-golden-lhr-unchanged.sh",