From 15201d86aa3b5246242293f0fd4bd9346073aad0 Mon Sep 17 00:00:00 2001
From: Luke Barnard <lukeb@openmarket.com>
Date: Mon, 15 May 2017 10:16:47 +0100
Subject: [PATCH] Prevent reskindex -w from running when file names have not
 changed

---
 scripts/reskindex.js | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/scripts/reskindex.js b/scripts/reskindex.js
index 1db22f9e10e..9516614fa55 100755
--- a/scripts/reskindex.js
+++ b/scripts/reskindex.js
@@ -8,8 +8,15 @@ var chokidar = require('chokidar');
 var componentIndex = path.join('src', 'component-index.js');
 var componentsDir = path.join('src', 'components');
 var componentGlob = '**/*.js';
+var prevFiles = [];
 
 function reskindex() {
+    var files = glob.sync(componentGlob, {cwd: componentsDir}).sort();
+    if (!filesHaveChanged(files, prevFiles)) {
+        return;
+    }
+    prevFiles = files;
+
     var header = args.h || args.header;
     var packageJson = JSON.parse(fs.readFileSync('./package.json'));
 
@@ -37,7 +44,6 @@ function reskindex() {
         strm.write("module.exports.components = {};\n");
     }
 
-    var files = glob.sync(componentGlob, {cwd: componentsDir}).sort();
     for (var i = 0; i < files.length; ++i) {
         var file = files[i].replace('.js', '');
 
@@ -54,6 +60,20 @@ function reskindex() {
     console.log('Reskindex: completed');
 }
 
+// Expects both arrays of file names to be sorted
+function filesHaveChanged(files, prevFiles) {
+    if (files.length !== prevFiles.length) {
+        return true;
+    }
+    // Check for name changes
+    for (var i = 0; i < files.length; i++) {
+        if (prevFiles[i] !== files[i]) {
+            return true;
+        }
+    }
+    return false;
+}
+
 // -w indicates watch mode where any FS events will trigger reskindex
 if (!args.w) {
     reskindex();