Bug 1881265 - Enable ESLint recommended rule getter-return. r=mossop,extension-reviewers,devtools-reviewers,omc-reviewers,nchevobbe,aminomancer,robwu

Differential Revision: https://phabricator.services.mozilla.com/D202318

browser/components/aboutwelcome/.eslintrc.js

@@ -124,7 +124,6 @@ module.exports = {
     "consistent-this": ["error", "use-bind"],
     eqeqeq: "error",
     "func-name-matching": "error",
-    "getter-return": "error",
     "guard-for-in": "error",
     "max-nested-callbacks": ["error", 4],
     "max-params": ["error", 6],

browser/components/asrouter/.eslintrc.js

@@ -94,7 +94,6 @@ module.exports = {
     "consistent-this": ["error", "use-bind"],
     eqeqeq: "error",
     "func-name-matching": "error",
-    "getter-return": "error",
     "guard-for-in": "error",
     "max-nested-callbacks": ["error", 4],
     "max-params": ["error", 6],

browser/components/newtab/.eslintrc.js

@@ -123,7 +123,6 @@ module.exports = {
     "consistent-this": ["error", "use-bind"],
     eqeqeq: "error",
     "func-name-matching": "error",
-    "getter-return": "error",
     "guard-for-in": "error",
     "max-nested-callbacks": ["error", 4],
     "max-params": ["error", 6],

browser/components/reportbrokensite/test/browser/head.js

@@ -558,11 +558,17 @@ class MenuHelper {
     return true;
   }
 
-  get reportBrokenSite() {}
+  get reportBrokenSite() {
+    throw new Error("Should be defined in derived class");
+  }
 
-  get reportSiteIssue() {}
+  get reportSiteIssue() {
+    throw new Error("Should be defined in derived class");
+  }
 
-  get popup() {}
+  get popup() {
+    throw new Error("Should be defined in derived class");
+  }
 
   get opened() {
     return this.popup?.hasAttribute("panelopen");

devtools/server/devtools-server-connection.js

@@ -73,14 +73,6 @@ DevToolsServerConnection.prototype = {
     return this._prefix;
   },
 
-  /**
-   * For a DevToolsServerConnection used in content processes,
-   * returns the prefix of the connection it originates from, from the parent process.
-   */
-  get parentPrefix() {
-    this.prefix.replace(/child\d+\//, "");
-  },
-
   _transport: null,
   get transport() {
     return this._transport;

dom/promise/tests/unit/test_promise_job_across_sandbox.js

@@ -175,6 +175,7 @@ add_task(async function testThenableJobAccessError() {
   sandbox.thenable = {
     get then() {
       accessed = true;
+      return undefined;
     },
   };
 

js/xpconnect/tests/chrome/test_xrayToJS.xhtml

@@ -800,7 +800,7 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=933681
     checkThrows(function() { trickyObject.hasOwnProperty = 33; }, /shadow/,
                 "Should reject shadowing of pre-existing inherited properties over Xrays");
 
-    checkThrows(function() { Object.defineProperty(trickyObject, 'rejectedProp', { get() {}}); },
+    checkThrows(function() { Object.defineProperty(trickyObject, 'rejectedProp', { get() { return undefined; }}); },
                 /accessor property/, "Should reject accessor property definition");
   }
 

toolkit/components/extensions/ExtensionParent.sys.mjs

@@ -716,6 +716,7 @@ class ExtensionPageContextParent extends ProxyContextParent {
     if (this.viewType !== "background") {
       return this.appWindow;
     }
+    return undefined;
   }
 
   get tabId() {
@@ -724,6 +725,7 @@ class ExtensionPageContextParent extends ProxyContextParent {
     if (data.tabId >= 0) {
       return data.tabId;
     }
+    return undefined;
   }
 
   unload() {

toolkit/components/extensions/parent/ext-downloads.js

@@ -212,6 +212,7 @@ class DownloadItem {
       let timeLeftInSeconds = sizeLeft / this.download.speed;
       return new Date(Date.now() + timeLeftInSeconds * 1000);
     }
+    return undefined;
   }
 
   get state() {

toolkit/components/extensions/parent/ext-tabs-base.js

@@ -199,15 +199,16 @@ class TabBase {
   }
 
   /**
-   * @property {string | null} url
+   * @property {string | undefined} url
    *        Returns the current URL of this tab if the extension has permission
-   *        to read it, or null otherwise.
+   *        to read it, or undefined otherwise.
    *        @readonly
    */
   get url() {
     if (this.hasTabPermission) {
       return this._url;
     }
+    return undefined;
   }
 
   /**
@@ -230,15 +231,16 @@ class TabBase {
   }
 
   /**
-   * @property {nsIURI | null} title
+   * @property {nsIURI | undefined} title
    *        Returns the current title of this tab if the extension has permission
-   *        to read it, or null otherwise.
+   *        to read it, or undefined otherwise.
    *        @readonly
    */
   get title() {
     if (this.hasTabPermission) {
       return this._title;
     }
+    return undefined;
   }
 
   /**
@@ -253,15 +255,16 @@ class TabBase {
   }
 
   /**
-   * @property {nsIURI | null} faviconUrl
+   * @property {nsIURI | undefined} faviconUrl
    *        Returns the current faviron URL of this tab if the extension has permission
-   *        to read it, or null otherwise.
+   *        to read it, or undefined otherwise.
    *        @readonly
    */
   get favIconUrl() {
     if (this.hasTabPermission) {
       return this._favIconUrl;
     }
+    return undefined;
   }
 
   /**
@@ -1165,9 +1168,9 @@ class WindowBase {
   }
 
   /**
-   * @property {nsIURI | null} title
+   * @property {nsIURI | undefined} title
    *        Returns the current title of this window if the extension has permission
-   *        to read it, or null otherwise.
+   *        to read it, or undefined otherwise.
    *        @readonly
    */
   get title() {
@@ -1176,6 +1179,7 @@ class WindowBase {
     if (this.activeTab && this.activeTab.hasTabPermission) {
       return this._title;
     }
+    return undefined;
   }
 
   // The JSDoc validator does not support @returns tags in abstract functions or

toolkit/components/extensions/test/xpcshell/test_ext_api_events_listener_calls_exceptions.js

@@ -141,6 +141,7 @@ add_task(async function test_api_listener_call_exception() {
         // catch with a failure if we are running the extension code as a side effect
         // of logging the error to the console service.
         const nonError = {
+          // eslint-disable-next-line getter-return
           get message() {
             browser.test.fail(`Unexpected extension code executed`);
           },

toolkit/mozapps/extensions/internal/SitePermsAddonProvider.sys.mjs

@@ -148,20 +148,30 @@ class SitePermsAddonWrapper {
     });
   }
 
-  get creator() {}
+  get creator() {
+    return undefined;
+  }
 
-  get homepageURL() {}
+  get homepageURL() {
+    return undefined;
+  }
 
-  get description() {}
+  get description() {
+    return undefined;
+  }
 
-  get fullDescription() {}
+  get fullDescription() {
+    return undefined;
+  }
 
   get version() {
     // We consider the previous implementation attempt (signed addons) to be the initial version,
     // hence the 2.0 for this approach.
     return "2.0";
   }
-  get updateDate() {}
+  get updateDate() {
+    return undefined;
+  }
 
   get isActive() {
     return true;

tools/lint/eslint/eslint-plugin-mozilla/lib/configs/recommended.js

@@ -165,10 +165,6 @@ module.exports = {
     // No credentials submitted with fetch calls
     "fetch-options/no-fetch-credentials": "off",
 
-    // XXX This rule line should be removed to enable it. See bug 1487642.
-    // Enforce return statements in getters
-    "getter-return": "off",
-
     // Maximum depth callbacks can be nested.
     "max-nested-callbacks": ["error", 10],