♻️ Fully pass typechecking in #experiments + references cleanup (#37214)

* Set up #experiments for typechecking

* Enable partial typechecking on #experiments

* Rename *-globals.d.ts files for convention/consistency

* Remove extern file

* Use reference comment tag where trivial

* Partial type-checking for #experiments

* Forbidden terms

* Lint fixes

* Split up some .d.ts files

* Revert references tags

* Include all core .d.ts files

* Fix All The Things!

* Lint fixes

* Remove unneeded assertions

* Merge in and use shared config

* Comment out local/no-duplicate-name-typedef

* Lint fixes

* Un-rename accidental rename

* Fix @ const {string} for prop literals

* Fix remaining type errors after removing allowance

* Remove unneeded annotations on FORM_PROP_

ads/google/a4a/experiment-utils.js

@@ -4,7 +4,6 @@ import {
   getExperimentBranch,
   randomlySelectUnsetExperiments,
 } from '#experiments';
-import {ExperimentInfoDef} from '#experiments/experiments.type';
 
 /**
  * Attempts to select into experiment and forces branch if selected.

build-system/tasks/check-types.js

@@ -23,6 +23,7 @@ const TSC_TYPECHECK_TARGETS = {
   'compiler': 'src/compiler',
   'carousel': 'extensions/amp-carousel/0.1',
   'core': 'src/core',
+  'experiments': 'src/experiments',
 };
 
 /**

build-system/test-configs/forbidden-terms.js

@@ -607,10 +607,7 @@ const forbiddenTermsGlobal = {
   '\\b(__)?AMP_EXP\\b': {
     message:
       'Do not access AMP_EXP directly. Use isExperimentOn() to access config',
-    allowlist: [
-      'src/experiments/index.js',
-      'src/experiments/experiments.extern.js',
-    ],
+    allowlist: ['src/experiments/index.js'],
   },
   'AMP_CONFIG': {
     message:

src/.eslintrc.js

@@ -1,4 +1,3 @@
-
 const {isCiBuild} = require('../build-system/common/ci');
 
 module.exports = {
@@ -54,9 +53,7 @@ module.exports = {
     },
     {
       'files': [
-        './core/window/window.extern.js',
         './polyfills/custom-elements.extern.js',
-        './experiments/experiments.extern.js',
         './experiments/shame.extern.js',
       ],
       'rules': {'local/no-global': 0},

src/core/amp-config.d.ts

@@ -2,8 +2,15 @@ export {};
 
 declare global {
   // AMP configuration and runtime settings structure.
-  interface AmpConfigDef {
+  interface AmpConfig {
     test?: boolean;
     localDev?: boolean;
+    canary?: boolean;
+    type?: string;
+  }
+
+  interface Window {
+    // AMP Runtime settings, configuration, and environment/build constants.
+    AMP_CONFIG?: AmpConfig & {[key: string]: (boolean|string)};
   }
 }

src/core/amp-mode.d.ts

@@ -0,0 +1,12 @@
+export {};
+
+declare global {
+  interface AmpModeObject {
+    esm: boolean;
+  }
+
+  interface Window {
+    // AMP Mode, used to force an override in tests.
+    __AMP_MODE: AmpModeObject;
+  }
+}

src/core/assert/assert-globals.d.ts

@@ -0,0 +1,11 @@
+export {};
+
+declare global {
+  interface Window {
+    // Never exists; used as part of post-compilation checks to verify DCE.
+    __AMP_ASSERTION_CHECK: undefined;
+
+    // Global error reporting handler; only present in AMP pages.
+    __AMP_REPORT_ERROR?: (this: Window, err: Error, opt_el?: Element) => void;
+  }
+}

src/core/assert/error.d.ts

@@ -2,6 +2,6 @@ export {};
 
 declare global {
   interface Error {
-    messageArray?: Array<any>;
+    messageArray?: any[];
   }
 }

src/core/data-structures/weakref.d.ts → src/core/data-structures/weakref-globals.d.ts

@@ -3,5 +3,8 @@ export {};
 declare global {
   interface Window {
     WeakRef?: typeof WeakRef;
+
+    // Counter for the DomBaseWeakRef polyfill.
+    __AMP_WEAKREF_ID?: number;
   }
 }

src/core/dom/amp-element-helpers.js

@@ -1,10 +1,7 @@
 import {devAssert} from '#core/assert';
 import {Deferred} from '#core/data-structures/promise';
 
-/** @const {string} */
 export const UPGRADE_TO_CUSTOMELEMENT_PROMISE = '__AMP_UPG_PRM';
-
-/** @const {string} */
 export const UPGRADE_TO_CUSTOMELEMENT_RESOLVER = '__AMP_UPG_RES';
 
 /**

src/core/dom/form.js

@@ -3,7 +3,6 @@ import {ancestorElementsByTag} from '#core/dom/query';
 import {toArray} from '#core/types/array';
 import {dict} from '#core/types/object';
 
-/** @const {string} */
 const FORM_PROP_ = '__AMP_FORM';
 
 /**

src/core/error/message-helpers.js

@@ -6,14 +6,10 @@ import {isElement} from '#core/types';
  * This is added to user error messages, so that we can later identify
  * them, when the only thing that we have is the message. This is the
  * case in many browsers when the global exception handler is invoked.
- *
- * @const {string}
  */
 export const USER_ERROR_SENTINEL = '\u200B\u200B\u200B';
 /**
  * Four zero width space.
- *
- * @const {string}
  */
 export const USER_ERROR_EMBED_SENTINEL = '\u200B\u200B\u200B\u200B';
 

src/core/tsconfig.json

@@ -1,5 +1,5 @@
 {
-  "compilerOptions": {"baseUrl": "../.."},
   "extends": "../../tsconfig.base.json",
+  "compilerOptions": {"baseUrl": "../.."},
   "include": ["**/*.js", "**/*.d.ts"]
 }

src/core/window/window.d.ts

@@ -2,25 +2,10 @@ export {};
 
 declare global {
   interface Window {
-    // Never exists; used as part of post-compilation checks to verify DCE.
-    __AMP_ASSERTION_CHECK: undefined;
-
-    // Global error reporting handler; only present in AMP pages.
-    __AMP_REPORT_ERROR?: (this: Window, err: Error, opt_el?: Element) => void;
-
     // Global property set by test some harnesses to signal a testing environment.
     __AMP_TEST?: boolean;
 
     // Global property set by test some harnesses to signal karma testing environment.
     __karma__?: boolean;
-
-    // Counter for the DomBaseWeakRef polyfill.
-    __AMP_WEAKREF_ID?: number;
-
-    // AMP Runtime settings, configuration, and environment/build constants.
-    AMP_CONFIG?: AmpConfigDef;
-
-    // AMP Mode, used to force an override in tests.
-    __AMP_MODE: {esm: boolean};
   }
 }

src/experiments/experiments-globals.d.ts

@@ -0,0 +1,10 @@
+export {};
+
+declare global {
+  interface Window {
+    __AMP_EXPERIMENT_BRANCHES?: import('./types.d').ExperimentBranchMap;
+    __AMP__EXPERIMENT_TOGGLES?: {[key: string]: boolean};
+    __AMP_EXP?: HTMLScriptElement;
+    AMP_EXP?: {[key: string]: number};
+  }
+}