Added git pre commit hook for checking the contents of icons.json

.githooks/pre-commit

@@ -0,0 +1,4 @@
+#!/bin/sh
+
+yarn checkIcons
+exit $?

icons.json

@@ -4882,4 +4882,4 @@
       "icon": "cloud-sun"
     }
   }
-}
+}

package.json

@@ -39,7 +39,8 @@
     "addtags": "babel-node ./scripts/addMissingKeysToTags.js --presets @babel/env",
     "tags2icons": "babel-node ./scripts/migrateTagsToIcons.js --presets @babel/env",
     "icons2tags": "babel-node ./scripts/migrateIconsToTags.js --presets @babel/env",
-    "generate:changelog": "babel-node ./scripts/generateChangelog.js --presets @babel/env"
+    "generate:changelog": "babel-node ./scripts/generateChangelog.js --presets @babel/env",
+    "checkIcons": "babel-node ./scripts/checkIconsAndCategories.js --presets @babel/env"
   },
   "devDependencies": {
     "@ampproject/rollup-plugin-closure-compiler": "^0.25.2",

scripts/checkIconsAndCategories.js

@@ -0,0 +1,49 @@
+import path from 'path';
+import icons from '../icons.json';
+import {readSvgDirectory} from './helpers';
+
+const ICONS_DIR = path.resolve(__dirname, '../icons');
+
+console.log(`Read all icons`);
+
+const svgFiles = readSvgDirectory(ICONS_DIR);
+
+const iconNames = svgFiles.map(icon => icon.split('.')[0]);
+
+let error = false;
+
+iconNames.forEach(iconName => {
+  if (typeof icons.icons[iconName] === 'undefined') {
+    console.error(`'${iconName}.svg' is not present in 'icons.json'.`);
+    error = true;
+  }
+});
+
+Object.keys(icons.icons).forEach(iconName => {
+  const icon = icons.icons[iconName];
+  if (iconNames.indexOf(iconName) === -1) {
+    console.error(`'${iconName}.svg' does not exist.`);
+    error = true;
+  }
+  icon.categories.forEach(categoryName => {
+    if (typeof icons.categories[categoryName] === 'undefined') {
+      console.error(`Icon '${iconName}' refers to the non-existing category '${categoryName}'.`);
+      error = true;
+    }
+  });
+});
+
+Object.keys(icons.categories).forEach(categoryName => {
+  const category = icons.categories[categoryName];
+  if (!category.icon) {
+    console.error(`Category '${categoryName}' does not use an icon '${category.icon}'.`);
+    error = true;
+  } else if (typeof icons.icons[category.icon] === 'undefined') {
+    console.error(`Category '${categoryName}' uses the non-existing icon '${category.icon}'.`);
+    error = true;
+  }
+});
+
+if (error) {
+  throw new Error('At least one error in icons.json prevents from committing changes.');
+}