ignore files listed in the prettierignore file

3 files changed, 40 insertions, 8 deletions

diff --git a/package.json b/package.json
index c81020f631e..56fd2575e91 100644
--- a/package.json
+++ b/package.json
@@ -107,6 +107,7 @@
     "eslint-plugin-jasmine": "^2.1.0",
     "eslint-plugin-promise": "^3.5.0",
     "eslint-plugin-vue": "^4.0.1",
+    "ignore": "^3.3.7",
     "istanbul": "^0.4.5",
     "jasmine-core": "^2.9.0",
     "jasmine-jquery": "^2.1.1",
diff --git a/scripts/frontend/prettier.js b/scripts/frontend/prettier.js
index 2708340b48e..5b185b8a70a 100644
--- a/scripts/frontend/prettier.js
+++ b/scripts/frontend/prettier.js
@@ -1,6 +1,9 @@
+/* eslint import/no-commonjs: "off", import/no-extraneous-dependencies: "off", no-console: "off" */
 const glob = require('glob');
 const prettier = require('prettier');
 const fs = require('fs');
+const path = require('path');
+const prettierIgnore = require('ignore')();
 
 const getStagedFiles = require('./frontend_script_utils').getStagedFiles;
 
@@ -10,18 +13,33 @@ const allFiles = mode === 'check-all' || mode === 'save-all';
 
 const config = {
   patterns: ['**/*.js', '**/*.vue', '**/*.scss'],
-  ignore: ['**/node_modules/**', '**/vendor/**', '**/public/**'],
   parsers: {
     js: 'babylon',
     vue: 'vue',
     scss: 'css',
   },
 };
+
+/*
+ * Unfortunately the prettier API does not expose support for .prettierignore files, they however
+ * use the ignore package, so we do the same. We simply cannot use the glob package, because
+ * gitignore style is not compatible with globs ignore style.
+ */
+prettierIgnore.add(
+  fs
+    .readFileSync(path.join(__dirname, '../../', '.prettierignore'))
+    .toString()
+    .trim()
+    .split(/\r?\n/),
+);
+
 const availableExtensions = Object.keys(config.parsers);
 
 console.log(`Loading ${allFiles ? 'All' : 'Staged'} Files ...`);
 
-const stagedFiles = allFiles ? null : getStagedFiles(availableExtensions.map(ext => `*.${ext}`));
+const stagedFiles = allFiles
+  ? null
+  : getStagedFiles(availableExtensions.map(ext => `*.${ext}`));
 
 if (stagedFiles) {
   if (!stagedFiles.length || (stagedFiles.length === 1 && !stagedFiles[0])) {
@@ -35,15 +53,28 @@ let didWarn = false;
 let didError = false;
 
 let files;
+
+// Read
 if (allFiles) {
-  const ignore = config.ignore;
   const patterns = config.patterns;
-  const globPattern = patterns.length > 1 ? `{${patterns.join(',')}}` : `${patterns.join(',')}`;
-  files = glob.sync(globPattern, { ignore }).filter(f => allFiles || stagedFiles.includes(f));
+  /*
+   * The ignore patterns below are just to reduce search time on the system, as it includes the
+   * folders with the most ignored assets, the actual prettierignore will be used later on
+   */
+  const ignore = ['**/node_modules/**', '**/vendor/**', '**/public/**'];
+  const globPattern =
+    patterns.length > 1 ? `{${patterns.join(',')}}` : `${patterns.join(',')}`;
+  files = glob
+    .sync(globPattern, { ignore })
+    .filter(f => allFiles || stagedFiles.includes(f));
 } else {
-  files = stagedFiles.filter(f => availableExtensions.includes(f.split('.').pop()));
+  files = stagedFiles.filter(f =>
+    availableExtensions.includes(f.split('.').pop()),
+  );
 }
 
+files = prettierIgnore.filter(files);
+
 if (!files.length) {
   console.log('No Files found to process with Prettier');
   return;
@@ -73,7 +104,7 @@ prettier
         } else if (!prettier.check(input, options)) {
           if (!didWarn) {
             console.log(
-              '\n===============================\nGitLab uses Prettier to format all JavaScript code.\nPlease format each file listed below or run "yarn prettier-staged-save"\n===============================\n'
+              '\n===============================\nGitLab uses Prettier to format all JavaScript code.\nPlease format each file listed below or run "yarn prettier-staged-save"\n===============================\n',
             );
             didWarn = true;
           }
diff --git a/yarn.lock b/yarn.lock
index 36683a2a480..af7bda5d562 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -4232,7 +4232,7 @@ ignore@^3.2.0:
   version "3.3.3"
   resolved "https://registry.yarnpkg.com/ignore/-/ignore-3.3.3.tgz#432352e57accd87ab3110e82d3fea0e47812156d"
 
-ignore@^3.3.5:
+ignore@^3.3.5, ignore@^3.3.7:
   version "3.3.7"
   resolved "https://registry.yarnpkg.com/ignore/-/ignore-3.3.7.tgz#612289bfb3c220e186a58118618d5be8c1bab021"