Defer package dependency checking

Move the checking of package dependencies to an idle callback. Also
opportunisticly loads the dependencies in the callback so they are ready
for the first lint call.

Fixes #59.

Author: Arcanemagus

lib/index.js

@@ -52,7 +52,17 @@ const loadDeps = () => {
 
 export default {
   activate() {
-    require('atom-package-deps').install('linter-htmlhint');
+    this.idleCallbacks = new Set();
+    let depsCallbackID;
+    const installLinterHtmlhintDeps = () => {
+      this.idleCallbacks.delete(depsCallbackID);
+      if (!atom.inSpecMode()) {
+        require('atom-package-deps').install('linter-htmlhint');
+      }
+      loadDeps();
+    };
+    depsCallbackID = window.requestIdleCallback(installLinterHtmlhintDeps);
+    this.idleCallbacks.add(depsCallbackID);
 
     this.grammarScopes = [];
 
@@ -66,6 +76,8 @@ export default {
   },
 
   deactivate() {
+    this.idleCallbacks.forEach(callbackID => window.cancelIdleCallback(callbackID));
+    this.idleCallbacks.clear();
     this.subscriptions.dispose();
   },
 

package.json

@@ -43,7 +43,7 @@
   "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",
     "strip-json-comments": "^2.0.1",
     "tiny-promisify": "^1.0.0"
@@ -75,6 +75,7 @@
       "atom": true
     },
     "env": {
+      "browser": true,
       "node": true
     }
   },