fixing cycles around assert

Author: ef4

packages/@ember/debug/index.ts

@@ -6,6 +6,7 @@ import defaultDeprecate from './lib/deprecate';
 import { isTesting } from './lib/testing';
 import type { WarnFunc } from './lib/warn';
 import _warn from './lib/warn';
+import { assert, setAssert } from './lib/assert';
 
 export { registerHandler as registerWarnHandler } from './lib/warn';
 export {
@@ -27,10 +28,6 @@ export type DebugFunctionType =
   | 'runInDebug'
   | 'deprecateFunc';
 
-export interface AssertFunc {
-  (desc: string, condition: unknown): asserts condition;
-  (desc: string): never;
-}
 export type DebugFunc = (message: string) => void;
 export type DebugSealFunc = (obj: object) => void;
 export type DebugFreezeFunc = (obj: object) => void;
@@ -43,7 +40,7 @@ export type DeprecateFuncFunc = (
 ) => Function;
 
 export type GetDebugFunction = {
-  (type: 'assert'): AssertFunc;
+  (type: 'assert'): typeof assert;
   (type: 'info'): InfoFunc;
   (type: 'warn'): WarnFunc;
   (type: 'debug'): DebugFunc;
@@ -55,7 +52,7 @@ export type GetDebugFunction = {
 };
 
 export type SetDebugFunction = {
-  (type: 'assert', func: AssertFunc): AssertFunc;
+  (type: 'assert', func: typeof assert): typeof assert;
   (type: 'info', func: InfoFunc): InfoFunc;
   (type: 'warn', func: WarnFunc): WarnFunc;
   (type: 'debug', func: DebugFunc): DebugFunc;
@@ -71,7 +68,6 @@ const noop = () => {};
 
 // SAFETY: these casts are just straight-up lies, but the point is that they do
 // not do anything in production builds.
-let assert: AssertFunc = noop as unknown as AssertFunc;
 let info: InfoFunc = noop;
 let warn: WarnFunc = noop;
 let debug: DebugFunc = noop;
@@ -94,7 +90,7 @@ if (DEBUG) {
   setDebugFunction = function (type: DebugFunctionType, callback: Function) {
     switch (type) {
       case 'assert':
-        return (assert = callback as AssertFunc);
+        return setAssert(callback as typeof assert);
       case 'info':
         return (info = callback as InfoFunc);
       case 'warn':
@@ -143,51 +139,6 @@ if (DEBUG) {
 */
 
 if (DEBUG) {
-  /**
-    Verify that a certain expectation is met, or throw a exception otherwise.
-
-    This is useful for communicating assumptions in the code to other human
-    readers as well as catching bugs that accidentally violates these
-    expectations.
-
-    Assertions are removed from production builds, so they can be freely added
-    for documentation and debugging purposes without worries of incuring any
-    performance penalty. However, because of that, they should not be used for
-    checks that could reasonably fail during normal usage. Furthermore, care
-    should be taken to avoid accidentally relying on side-effects produced from
-    evaluating the condition itself, since the code will not run in production.
-
-    ```javascript
-    import { assert } from '@ember/debug';
-
-    // Test for truthiness
-    assert('Must pass a string', typeof str === 'string');
-
-    // Fail unconditionally
-    assert('This code path should never be run');
-    ```
-
-    @method assert
-    @static
-    @for @ember/debug
-    @param {String} description Describes the expectation. This will become the
-      text of the Error thrown if the assertion fails.
-    @param {any} condition Must be truthy for the assertion to pass. If
-      falsy, an exception will be thrown.
-    @public
-    @since 1.0.0
-  */
-  function assert(desc: string): never;
-  function assert(desc: string, test: unknown): asserts test;
-  // eslint-disable-next-line no-inner-declarations
-  function assert(desc: string, test?: unknown): asserts test {
-    if (!test) {
-      throw new Error(`Assertion Failed: ${desc}`);
-    }
-  }
-
-  setDebugFunction('assert', assert);
-
   /**
     Display a debug notice.
 

packages/@ember/debug/lib/assert.ts

@@ -0,0 +1,59 @@
+import { DEBUG } from '@glimmer/env';
+
+export interface AssertFunc {
+  (desc: string, condition: unknown): asserts condition;
+  (desc: string): never;
+}
+
+export let assert: AssertFunc = (() => {}) as unknown as AssertFunc;
+
+export function setAssert(implementation: typeof assert): typeof assert {
+  assert = implementation;
+  return implementation;
+}
+
+if (DEBUG) {
+  /**
+    Verify that a certain expectation is met, or throw a exception otherwise.
+
+    This is useful for communicating assumptions in the code to other human
+    readers as well as catching bugs that accidentally violates these
+    expectations.
+
+    Assertions are removed from production builds, so they can be freely added
+    for documentation and debugging purposes without worries of incuring any
+    performance penalty. However, because of that, they should not be used for
+    checks that could reasonably fail during normal usage. Furthermore, care
+    should be taken to avoid accidentally relying on side-effects produced from
+    evaluating the condition itself, since the code will not run in production.
+
+    ```javascript
+    import { assert } from '@ember/debug';
+
+    // Test for truthiness
+    assert('Must pass a string', typeof str === 'string');
+
+    // Fail unconditionally
+    assert('This code path should never be run');
+    ```
+
+    @method assert
+    @static
+    @for @ember/debug
+    @param {String} description Describes the expectation. This will become the
+      text of the Error thrown if the assertion fails.
+    @param {any} condition Must be truthy for the assertion to pass. If
+      falsy, an exception will be thrown.
+    @public
+    @since 1.0.0
+  */
+  function assert(desc: string): never;
+  function assert(desc: string, test: unknown): asserts test;
+  // eslint-disable-next-line no-inner-declarations
+  function assert(desc: string, test?: unknown): asserts test {
+    if (!test) {
+      throw new Error(`Assertion Failed: ${desc}`);
+    }
+  }
+  setAssert(assert);
+}

packages/@ember/debug/lib/deprecate.ts

@@ -1,7 +1,7 @@
 import { ENV } from '@ember/-internals/environment';
 import { DEBUG } from '@glimmer/env';
 
-import { assert } from '../index';
+import { assert } from './assert';
 import type { HandlerCallback } from './handlers';
 import { invoke, registerHandler as genericRegisterHandler } from './handlers';
 

packages/@ember/debug/lib/inspect.ts

@@ -1,4 +1,4 @@
-import { assert } from '@ember/debug';
+import { assert } from './assert';
 const { toString: objectToString } = Object.prototype;
 const { toString: functionToString } = Function.prototype;
 const { isArray } = Array;

packages/@ember/debug/lib/warn.ts

@@ -1,6 +1,6 @@
 import { DEBUG } from '@glimmer/env';
 
-import { assert } from '../index';
+import { assert } from './assert';
 import type { HandlerCallback } from './handlers';
 import { invoke, registerHandler as genericRegisterHandler } from './handlers';