Allowed describe and it/test to take in functions again

packages/jest-circus/src/index.ts

@@ -7,24 +7,24 @@
 
 import type {Circus, Global} from '@jest/types';
 import {bind as bindEach} from 'jest-each';
-import {ErrorWithStack, isPromise} from 'jest-util';
+import {ErrorWithStack, convertDescriptorToString, isPromise} from 'jest-util';
 import {dispatchSync} from './state';
 
 export {setState, getState, resetState} from './state';
 export {default as run} from './run';
 
 type THook = (fn: Circus.HookFn, timeout?: number) => void;
 type DescribeFn = (
-  blockName: Circus.BlockName,
+  blockName: Circus.BlockNameLike,
   blockFn: Circus.BlockFn,
 ) => void;
 
 const describe = (() => {
-  const describe = (blockName: Circus.BlockName, blockFn: Circus.BlockFn) =>
+  const describe = (blockName: Circus.BlockNameLike, blockFn: Circus.BlockFn) =>
     _dispatchDescribe(blockFn, blockName, describe);
-  const only = (blockName: Circus.BlockName, blockFn: Circus.BlockFn) =>
+  const only = (blockName: Circus.BlockNameLike, blockFn: Circus.BlockFn) =>
     _dispatchDescribe(blockFn, blockName, only, 'only');
-  const skip = (blockName: Circus.BlockName, blockFn: Circus.BlockFn) =>
+  const skip = (blockName: Circus.BlockNameLike, blockFn: Circus.BlockFn) =>
     _dispatchDescribe(blockFn, blockName, skip, 'skip');
 
   describe.each = bindEach(describe, false);
@@ -40,7 +40,7 @@ const describe = (() => {
 
 const _dispatchDescribe = (
   blockFn: Circus.BlockFn,
-  blockName: Circus.BlockName,
+  blockName: Circus.BlockNameLike,
   describeFn: DescribeFn,
   mode?: Circus.BlockMode,
 ) => {
@@ -54,6 +54,7 @@ const _dispatchDescribe = (
     asyncError.message = `Invalid second argument, ${blockFn}. It must be a callback function.`;
     throw asyncError;
   }
+  blockName = convertDescriptorToString(blockName);
   dispatchSync({
     asyncError,
     blockName,

packages/jest-each/src/bind.ts

@@ -7,7 +7,7 @@
  */
 
 import type {Global} from '@jest/types';
-import {ErrorWithStack} from 'jest-util';
+import {ErrorWithStack, convertDescriptorToString} from 'jest-util';
 import convertArrayTable from './table/array';
 import convertTemplateTable from './table/template';
 import {
@@ -37,10 +37,11 @@ export default function bind<EachCallback extends Global.TestCallback>(
     ...taggedTemplateData: Global.TemplateData
   ) =>
     function eachBind(
-      title: string,
+      title: Global.BlockNameLike,
       test: Global.EachTestFn<EachCallback>,
       timeout?: number,
     ): void {
+      title = convertDescriptorToString(title);
       try {
         const tests = isArrayTable(taggedTemplateData)
           ? buildArrayTests(title, table)

packages/jest-types/__typetests__/globals.test.ts

@@ -58,6 +58,7 @@ expectType<void>(beforeEach(fn, timeout));
 expectType<void>(beforeEach(asyncFn, timeout));
 expectType<void>(beforeEach(genFn, timeout));
 
+expectType<void>(test(testName, fn));
 expectType<void>(test(testName, fn));
 expectType<void>(test(testName, asyncFn));
 expectType<void>(test(testName, doneFn));
@@ -247,27 +248,52 @@ expectType<void>(
 `(testName, asyncFn, timeout),
 );
 
+expectType<void>(describe(testName, fn));
+expectType<void>(describe(123, fn));
+expectType<void>(describe(() => {}, fn));
+expectType<void>(describe(function named() {}, fn));
+expectType<void>(describe(class {}, fn));
+expectType<void>(describe(class Named {}, fn));
+
 expectType<void>(describe.each(list)(testName, fn));
 expectType<void>(describe.each(list)(testName, fn, timeout));
 expectType<void>(describe.each(table)(testName, fn));
 expectType<void>(describe.each(table)(testName, fn, timeout));
 expectType<void>(describe.each(readonlyTable)(testName, fn));
 expectType<void>(describe.each(readonlyTable)(testName, fn, timeout));
 
+expectType<void>(describe.each(list)(testName, fn));
+expectType<void>(describe.each(list)(123, fn));
+expectType<void>(describe.each(list)(() => {}, fn));
+expectType<void>(describe.each(list)(function named() {}, fn));
+expectType<void>(describe.each(list)(class Named {}, fn));
+
 expectType<void>(describe.only.each(list)(testName, fn));
 expectType<void>(describe.only.each(list)(testName, fn, timeout));
 expectType<void>(describe.only.each(table)(testName, fn));
 expectType<void>(describe.only.each(table)(testName, fn, timeout));
 expectType<void>(describe.only.each(readonlyTable)(testName, fn));
 expectType<void>(describe.only.each(readonlyTable)(testName, fn, timeout));
 
+expectType<void>(describe.only.each(list)(testName, fn));
+expectType<void>(describe.only.each(list)(123, fn));
+expectType<void>(describe.only.each(list)(() => {}, fn));
+expectType<void>(describe.only.each(list)(function named() {}, fn));
+expectType<void>(describe.only.each(list)(class Named {}, fn));
+
 expectType<void>(describe.skip.each(list)(testName, fn));
 expectType<void>(describe.skip.each(list)(testName, fn, timeout));
 expectType<void>(describe.skip.each(table)(testName, fn));
 expectType<void>(describe.skip.each(table)(testName, fn, timeout));
 expectType<void>(describe.skip.each(readonlyTable)(testName, fn));
 expectType<void>(describe.skip.each(readonlyTable)(testName, fn, timeout));
 
+expectType<void>(describe.skip.each(list)(testName, fn));
+expectType<void>(describe.skip.each(list)(123, fn));
+expectType<void>(describe.skip.each(list)(() => {}, fn));
+expectType<void>(describe.skip.each(list)(function named() {}, fn));
+expectType<void>(describe.skip.each(list)(class Named {}, fn));
+
 expectType<void>(
   describe.each`
     a    | b    | expected

packages/jest-types/src/Circus.ts

@@ -12,6 +12,7 @@ type Process = NodeJS.Process;
 export type DoneFn = Global.DoneFn;
 export type BlockFn = Global.BlockFn;
 export type BlockName = Global.BlockName;
+export type BlockNameLike = Global.BlockNameLike;
 export type BlockMode = void | 'skip' | 'only' | 'todo';
 export type TestMode = BlockMode;
 export type TestName = Global.TestName;

packages/jest-types/src/Global.ts

@@ -27,6 +27,9 @@ export type GeneratorReturningTestFn = (
   this: TestContext | undefined,
 ) => TestReturnValueGenerator;
 
+// eslint-disable-next-line @typescript-eslint/ban-types
+export type NameLike = number | Function;
+
 export type TestName = string;
 export type TestFn =
   | PromiseReturningTestFn
@@ -35,6 +38,8 @@ export type TestFn =
 export type ConcurrentTestFn = () => TestReturnValuePromise;
 export type BlockFn = () => void;
 export type BlockName = string;
+export type BlockNameLike = BlockName | NameLike;
+
 export type HookFn = TestFn;
 
 export type Col = unknown;
@@ -51,15 +56,11 @@ export type EachTestFn<EachCallback extends TestCallback> = (
   ...args: ReadonlyArray<any>
 ) => ReturnType<EachCallback>;
 
-type Each<EachCallback extends TestCallback> =
+type Each<EachCallback extends TestCallback, Name> =
   | ((
       table: EachTable,
       ...taggedTemplateData: TemplateData
-    ) => (
-      name: BlockName | TestName,
-      test: EachTestFn<EachCallback>,
-      timeout?: number,
-    ) => void)
+    ) => (name: Name, test: EachTestFn<EachCallback>, timeout?: number) => void)
   | (() => () => void);
 
 export interface HookBase {
@@ -68,7 +69,7 @@ export interface HookBase {
 
 export interface ItBase {
   (testName: TestName, fn: TestFn, timeout?: number): void;
-  each: Each<TestFn>;
+  each: Each<TestFn, TestName>;
 }
 
 export interface It extends ItBase {
@@ -79,7 +80,7 @@ export interface It extends ItBase {
 
 export interface ItConcurrentBase {
   (testName: TestName, testFn: ConcurrentTestFn, timeout?: number): void;
-  each: Each<ConcurrentTestFn>;
+  each: Each<ConcurrentTestFn, TestName>;
 }
 
 export interface ItConcurrentExtended extends ItConcurrentBase {
@@ -92,8 +93,8 @@ export interface ItConcurrent extends It {
 }
 
 export interface DescribeBase {
-  (blockName: BlockName, blockFn: BlockFn): void;
-  each: Each<BlockFn>;
+  (blockName: BlockNameLike, blockFn: BlockFn): void;
+  each: Each<BlockFn, BlockNameLike | TestName>;
 }
 
 export interface Describe extends DescribeBase {

packages/jest-util/src/convertDescriptorToString.ts

@@ -5,35 +5,22 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-/* eslint-disable local/ban-types-eventually */
+import type {Global} from '@jest/types';
 
-// See: https://github.com/facebook/jest/pull/5154
-export default function convertDescriptorToString<
-  T extends number | string | Function | undefined,
->(descriptor: T): T | string {
-  if (
-    typeof descriptor === 'string' ||
-    typeof descriptor === 'number' ||
-    descriptor === undefined
-  ) {
-    return descriptor;
-  }
+export default function convertDescriptorToString(
+  descriptor: Global.BlockNameLike | undefined,
+): string {
+  switch (typeof descriptor) {
+    case 'function':
+      return descriptor.name;
 
-  if (typeof descriptor !== 'function') {
-    throw new Error('describe expects a class, function, number, or string.');
-  }
+    case 'number':
+    case 'undefined':
+      return `${descriptor}`;
 
-  if (descriptor.name !== undefined) {
-    return descriptor.name;
+    case 'string':
+      return descriptor;
   }
 
-  // Fallback for old browsers, pardon Flow
-  const stringified = descriptor.toString();
-  const typeDescriptorMatch = stringified.match(/class|function/);
-  const indexOfNameSpace =
-    // @ts-expect-error: typeDescriptorMatch exists
-    typeDescriptorMatch.index + typeDescriptorMatch[0].length;
-  const indexOfNameAfterSpace = stringified.search(/\(|\{/);
-  const name = stringified.substring(indexOfNameSpace, indexOfNameAfterSpace);
-  return name.trim();
+  throw new Error('describe expects a class, function, number, or string.');
 }