Merge pull request #166 from AtomLinter/arcanemagus/updates

Fix a few issues and make several enhancements to the code:
* Defer package dependency checking
* Guard against invalid `TextEditor`s, and ones without a path.
* Refactor to a default export
* Move dependency loading to a function

Author: Arcanemagus

lib/index.js

@@ -2,79 +2,126 @@
 
 // eslint-disable-next-line import/extensions, import/no-extraneous-dependencies
 import { CompositeDisposable } from 'atom';
-import { readFile as fsReadFile } from 'fs';
-import { dirname } from 'path';
 
-const lazyReq = require('lazy-req')(require);
-
-const { findAsync, generateRange } = lazyReq('atom-linter')('findAsync', 'generateRange');
-const stripJSONComments = lazyReq('strip-json-comments');
-const tinyPromisify = lazyReq('tiny-promisify');
-
-const grammarScopes = [];
-
-let subscriptions;
-
-export function activate() {
-  require('atom-package-deps').install('linter-htmlhint');
-
-  subscriptions = new CompositeDisposable();
-  subscriptions.add(atom.config.observe('linter-htmlhint.enabledScopes', (scopes) => {
-    // Remove any old scopes
-    grammarScopes.splice(0, grammarScopes.length);
-    // Add the current scopes
-    Array.prototype.push.apply(grammarScopes, scopes);
-  }));
-}
-
-export function deactivate() {
-  subscriptions.dispose();
-}
+// Dependencies
+let dirname;
+let HTMLHint;
+let findAsync;
+let fsReadFile;
+let generateRange;
+let tinyPromisify;
+let stripJSONComments;
 
 const getConfig = async (filePath) => {
-  const readFile = tinyPromisify()(fsReadFile);
+  const readFile = tinyPromisify(fsReadFile);
   const configPath = await findAsync(dirname(filePath), '.htmlhintrc');
   let conf = null;
   if (configPath !== null) {
     conf = await readFile(configPath, 'utf8');
   }
   if (conf) {
-    return JSON.parse(stripJSONComments()(conf));
+    return JSON.parse(stripJSONComments(conf));
   }
   return null;
 };
 
-export function provideLinter() {
-  return {
-    name: 'htmlhint',
-    grammarScopes,
-    scope: 'file',
-    lintOnFly: true,
-    lint: async (editor) => {
-      const { HTMLHint } = require('htmlhint');
-
-      const fileText = editor.getText();
-      const filePath = editor.getPath();
+const loadDeps = () => {
+  if (loadDeps.loaded) {
+    return;
+  }
+  if (!dirname) {
+    ({ dirname } = require('path'));
+  }
+  if (!HTMLHint) {
+    ({ HTMLHint } = require('htmlhint'));
+  }
+  if (!findAsync || !generateRange) {
+    ({ findAsync, generateRange } = require('atom-linter'));
+  }
+  if (!fsReadFile) {
+    ({ readFile: fsReadFile } = require('fs'));
+  }
+  if (!tinyPromisify) {
+    tinyPromisify = require('tiny-promisify');
+  }
+  if (!stripJSONComments) {
+    stripJSONComments = require('strip-json-comments');
+  }
+  loadDeps.loaded = true;
+};
 
-      if (!fileText) {
-        return [];
+export default {
+  activate() {
+    this.idleCallbacks = new Set();
+    let depsCallbackID;
+    const installLinterHtmlhintDeps = () => {
+      this.idleCallbacks.delete(depsCallbackID);
+      if (!atom.inSpecMode()) {
+        require('atom-package-deps').install('linter-htmlhint');
       }
-
-      const ruleset = await getConfig(filePath);
-
-      const messages = HTMLHint.verify(fileText, ruleset || undefined);
-
-      if (editor.getText() !== fileText) {
-        // Editor contents have changed, tell Linter not to update
-        return null;
+      loadDeps();
+    };
+    depsCallbackID = window.requestIdleCallback(installLinterHtmlhintDeps);
+    this.idleCallbacks.add(depsCallbackID);
+
+    this.grammarScopes = [];
+
+    this.subscriptions = new CompositeDisposable();
+    this.subscriptions.add(atom.config.observe('linter-htmlhint.enabledScopes', (scopes) => {
+      // Remove any old scopes
+      this.grammarScopes.splice(0, this.grammarScopes.length);
+      // Add the current scopes
+      Array.prototype.push.apply(this.grammarScopes, scopes);
+    }));
+  },
+
+  deactivate() {
+    this.idleCallbacks.forEach(callbackID => window.cancelIdleCallback(callbackID));
+    this.idleCallbacks.clear();
+    this.subscriptions.dispose();
+  },
+
+  provideLinter() {
+    return {
+      name: 'htmlhint',
+      grammarScopes: this.grammarScopes,
+      scope: 'file',
+      lintOnFly: true,
+      lint: async (editor) => {
+        if (!atom.workspace.isTextEditor(editor)) {
+          return null;
+        }
+
+        const filePath = editor.getPath();
+        if (!filePath) {
+          // Invalid path
+          return null;
+        }
+
+        const fileText = editor.getText();
+        if (!fileText) {
+          return [];
+        }
+
+        // Ensure that all dependencies are loaded
+        loadDeps();
+
+        const ruleset = await getConfig(filePath);
+
+        const messages = HTMLHint.verify(fileText, ruleset || undefined);
+
+        if (editor.getText() !== fileText) {
+          // Editor contents have changed, tell Linter not to update
+          return null;
+        }
+
+        return messages.map(message => ({
+          range: generateRange(editor, message.line - 1, message.col - 1),
+          type: message.type,
+          text: message.message,
+          filePath
+        }));
       }
-
-      return messages.map(message => ({
-        range: generateRange(editor, message.line - 1, message.col - 1),
-        type: message.type,
-        text: message.message,
-        filePath
-      }));
-    }
-  };
-}
+    };
+  }
+};

package.json

@@ -43,9 +43,8 @@
   "homepage": "https://github.com/AtomLinter/linter-htmlhint#readme",
   "dependencies": {
     "atom-linter": "^10.0.0",
-    "atom-package-deps": "^4.0.1",
+    "atom-package-deps": "^4.6.0",
     "htmlhint": "0.9.13",
-    "lazy-req": "^2.0.0",
     "strip-json-comments": "^2.0.1",
     "tiny-promisify": "^1.0.0"
   },
@@ -76,6 +75,7 @@
       "atom": true
     },
     "env": {
+      "browser": true,
       "node": true
     }
   },