Build: Require extensions for ES6 imports, prevent import cycles

mgol · web-flow · commit 44ac8c852917 · 2019-11-25T20:16:53.000+01:00
jQuery source is now authored in ECMAScript modules. Native browser support for them requires full file names including extensions. Rollup works even if import paths don't specify extensions, though, so one import slipped through without such an extension, breaking native browser import of src/jquery.js. A new ESLint rule using eslint-plugin-import prevents us from regressing on that front. Also, eslint-plugin-import's no-cycle rule is used to avoid import cycles. Closes gh-4544 Ref gh-4541 Ref 0753201
diff --git a/package.json b/package.json
@@ -30,6 +30,7 @@
     "commitplease": "3.2.0",
     "core-js-bundle": "3.0.0",
     "eslint-config-jquery": "2.0.0",
+    "eslint-plugin-import": "2.18.2",
     "grunt": "1.0.4",
     "grunt-babel": "8.0.0",
     "grunt-cli": "1.3.2",
diff --git a/src/.eslintrc.json b/src/.eslintrc.json
@@ -8,6 +8,13 @@
 		"sourceType": "module"
 	},
 
+	"plugins": [ "import" ],
+
+	"rules": {
+		"import/extensions": [ "error", "always" ],
+		"import/no-cycle": "error"
+	},
+
 	"overrides": [
 		{
 			"files": "wrapper.js",
