run ESLint

Several bugs were found (and fixed):
src/client/index.js:71
the following if() was equivalent to if (false in obj)

src/client/dom/element.js:207
the following if() was equivalent to if (!element || false in element)

src/client/rewrite/html.js:179
an undefined iterate() was referenced

Author: David Reed

.eslintignore

@@ -0,0 +1 @@
+dist

.eslintrc

@@ -0,0 +1,12 @@
+{
+    "env": {
+        "browser": true,
+        "worker": true,
+        "serviceworker": true,
+        "es6": true,
+        "node": true
+    },
+    "globals": { "globalThis": true, "importScripts": true },
+    "parserOptions": { "sourceType": "module", "ecmaVersion": "latest" },
+    "extends": ["eslint:recommended"]
+}

.prettierignore

@@ -0,0 +1 @@
+dist

package-lock.json

@@ -32,7 +32,7 @@
     "devDependencies": {
         "copy-webpack-plugin": "^11.0.0",
         "cross-env": "^7.0.3",
-        "eslint": "^8.8.0",
+        "eslint": "^8.28.0",
         "prettier": "^2.7.1",
         "terser-webpack-plugin": "^5.3.6",
         "webpack": "^5.74.0",

package.json

@@ -193,21 +193,6 @@ class DocumentHook extends EventEmitter {
             },
         });
     }
-    overrideReferrer() {
-        this.ctx.overrideDescriptor(this.docProto, 'referrer', {
-            get: (target, that) => {
-                const event = new HookEvent(
-                    { value: target.call(that) },
-                    target,
-                    that
-                );
-                this.emit('referrer', event);
-
-                if (event.intercepted) return event.returnValue;
-                return event.data.value;
-            },
-        });
-    }
     overrideCookie() {
         this.ctx.overrideDescriptor(this.docProto, 'cookie', {
             get: (target, that) => {

src/client/dom/document.js

@@ -204,7 +204,7 @@ class ElementApi extends EventEmitter {
         );
     }
     hookProperty(element, prop, handler) {
-        if (!element || !prop in element) return false;
+        if (!element || !(prop in element)) return false;
 
         if (this.ctx.nativeMethods.isArray(element)) {
             for (const elem of element) {

src/client/dom/element.js

@@ -68,7 +68,7 @@ class UVClient extends EventEmitter {
         );
     }
     override(obj, prop, wrapper, construct) {
-        if (!prop in obj) return false;
+        if (!(prop in obj)) return false;
         const wrapped = this.wrap(obj, prop, wrapper, construct);
         return (obj[prop] = wrapped);
     }
@@ -92,7 +92,7 @@ class UVClient extends EventEmitter {
                       },
                   }.attach;
 
-        if (!!construct) {
+        if (construct) {
             wrapped.prototype = fn.prototype;
             wrapped.prototype.constructor = wrapped;
         }

src/client/index.js

@@ -37,7 +37,7 @@ class LocationApi extends EventEmitter {
 
         for (const key of this.keys) {
             this.ctx.overrideDescriptor(this.workerLocProto, key, {
-                get: (target, that) => {
+                get: () => {
                     return parse(uv.href.get.call(this.location))[key];
                 },
             });
@@ -78,9 +78,12 @@ class LocationApi extends EventEmitter {
                                       );
                                       break;
                                   default:
-                                      const url = new URL(emulation.href);
-                                      url[key] = val;
-                                      that.location.href = wrap(url.href);
+                                      {
+                                          const url = new URL(emulation.href);
+                                          url[key] = val;
+                                          that.location.href = wrap(url.href);
+                                      }
+                                      break;
                               }
                           }
                         : undefined,

src/client/location.js

@@ -21,7 +21,7 @@ function validateCookie(cookie, meta, js = false) {
 
 async function db(openDB) {
     const db = await openDB('__op', 1, {
-        upgrade(db, oldVersion, newVersion, transaction) {
+        upgrade(db) {
             const store = db.createObjectStore('cookies', {
                 keyPath: 'id',
             });

src/rewrite/cookie.js

@@ -176,7 +176,7 @@ class P5Element extends EventEmitter {
         if (this.stream) return null;
 
         let str = '';
-        iterate(this.node, (node) => {
+        this.iterate(this.node, (node) => {
             if (node.nodeName === '#text') str += node.value;
         });
 

src/rewrite/html.js

@@ -365,7 +365,7 @@ export default (function (exports) {
      * Calculate specificity of a selector.
      * If the selector is a list, the max specificity is returned.
      */
-    function specificity(selector, { format = 'array' } = {}) {
+    function specificity(selector) {
         let ast =
             typeof selector === 'object'
                 ? selector

src/rewrite/parsel.js

@@ -1,5 +1,5 @@
 function attributes(ctx, meta = ctx.meta) {
-    const { html, js, css, attributePrefix, handlerScript, bundleScript } = ctx;
+    const { html, js, attributePrefix } = ctx;
     const origPrefix = attributePrefix + '-attr-';
 
     html.on('attr', (attr, type) => {
@@ -68,8 +68,8 @@ function attributes(ctx, meta = ctx.meta) {
     });
 }
 
-function text(ctx, meta = ctx.meta) {
-    const { html, js, css, attributePrefix } = ctx;
+function text(ctx) {
+    const { html, js, css } = ctx;
 
     html.on('text', (text, type) => {
         if (text.element.tagName === 'script') {
@@ -181,8 +181,7 @@ function isEvent(name) {
 }
 
 function injectHead(ctx) {
-    const { html, js, css, attributePrefix } = ctx;
-    const origPrefix = attributePrefix + '-attr-';
+    const { html } = ctx;
     html.on('element', (element, type) => {
         if (type !== 'rewrite') return false;
         if (element.tagName !== 'head') return false;

src/rewrite/rewrite.html.js

@@ -261,54 +261,61 @@ function unwrap(ctx) {
 
         switch (node.callee.property.name) {
             case '$wrap':
-                if (
-                    !node.arguments ||
-                    node.parent.type !== Syntax.MemberExpression ||
-                    node.parent.property !== node
-                )
-                    return false;
-                const [property] = node.arguments;
+                {
+                    if (
+                        !node.arguments ||
+                        node.parent.type !== Syntax.MemberExpression ||
+                        node.parent.property !== node
+                    )
+                        return false;
+                    const [property] = node.arguments;
 
-                data.changes.push({
-                    start: node.callee.start,
-                    end: property.start,
-                });
-
-                node.iterateEnd = function () {
                     data.changes.push({
-                        start: node.end - 2,
-                        end: node.end,
+                        start: node.callee.start,
+                        end: property.start,
                     });
-                };
+
+                    node.iterateEnd = function () {
+                        data.changes.push({
+                            start: node.end - 2,
+                            end: node.end,
+                        });
+                    };
+                }
                 break;
             case '$get':
             case 'rewriteUrl':
-                const [arg] = node.arguments;
+                {
+                    const [arg] = node.arguments;
 
-                data.changes.push({
-                    start: node.callee.start,
-                    end: arg.start,
-                });
-
-                node.iterateEnd = function () {
                     data.changes.push({
-                        start: node.end - 1,
-                        end: node.end,
+                        start: node.callee.start,
+                        end: arg.start,
                     });
-                };
+
+                    node.iterateEnd = function () {
+                        data.changes.push({
+                            start: node.end - 1,
+                            end: node.end,
+                        });
+                    };
+                }
                 break;
             case 'rewrite':
-                const [script] = node.arguments;
-                data.changes.push({
-                    start: node.callee.start,
-                    end: script.start,
-                });
-                node.iterateEnd = function () {
+                {
+                    const [script] = node.arguments;
                     data.changes.push({
-                        start: node.end - 1,
-                        end: node.end,
+                        start: node.callee.start,
+                        end: script.start,
                     });
-                };
+                    node.iterateEnd = function () {
+                        data.changes.push({
+                            start: node.end - 1,
+                            end: node.end,
+                        });
+                    };
+                }
+                break;
         }
     });
 }

src/rewrite/rewrite.script.js

@@ -1,3 +1,4 @@
+/*global UVServiceWorker*/
 importScripts('/uv.bundle.js');
 importScripts('/uv.config.js');
 importScripts('/uv.sw.js');

src/sw.js

@@ -1,3 +1,4 @@
+/*global Ultraviolet*/
 self.__uv$config = {
     prefix: '/service/',
     bare: 'https://incog.dev/bare/',

src/uv.config.js

@@ -481,7 +481,7 @@ function __uvHook(window, config = {}, bare = '/bare/') {
     });
 
     client.overrideDescriptor(window, 'origin', {
-        get: (target, that) => {
+        get: () => {
             return __uv.location.origin;
         },
     });
@@ -1318,20 +1318,13 @@ function __uvHook(window, config = {}, bare = '/bare/') {
     });
 
     // Proper hash emulation.
-    if (!!window.window) {
-        __uv.addEventListener.call(window, 'hashchange', (event) => {
-            if (event.__uv$dispatched) return false;
-            event.stopImmediatePropagation();
-            const hash = window.location.hash;
-            client.history.replaceState.call(
-                window.history,
-                '',
-                '',
-                event.oldURL
-            );
-            __uv.location.hash = hash;
-        });
-    }
+    __uv.addEventListener.call(window, 'hashchange', (event) => {
+        if (event.__uv$dispatched) return false;
+        event.stopImmediatePropagation();
+        const hash = window.location.hash;
+        client.history.replaceState.call(window.history, '', '', event.oldURL);
+        __uv.location.hash = hash;
+    });
 
     client.location.on('hashchange', (oldUrl, newUrl, ctx) => {
         if (ctx.HashChangeEvent && client.history.replaceState) {

src/uv.handler.js

@@ -1,3 +1,4 @@
+/*globals __uv$config*/
 // Users must import the config (and bundle) prior to importing uv.sw.js
 // This is to allow us to produce a generic bundle with no hard-coded paths.
 
@@ -29,7 +30,6 @@ const cspHeaders = [
     'x-xss-protection',
 ];
 const emptyMethods = ['GET', 'HEAD'];
-const emptyStatus = [204, 304];
 
 class UVServiceWorker extends Ultraviolet.EventEmitter {
     constructor(config = __uv$config) {

src/uv.sw.js

@@ -1,4 +1,3 @@
-import webpack from 'webpack';
 import { fileURLToPath } from 'url';
 import TerserPlugin from 'terser-webpack-plugin';
 import CopyPlugin from 'copy-webpack-plugin';