fix: fixed regression with using tests and fixture methods (#7491)

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[closes #7482]

## Purpose
_Describe the problem you want to address or the feature you want to
implement._

## Approach
_Describe how your changes address the issue or implement the desired
functionality in as much detail as possible._

## References
#7482

## Pre-Merge TODO
- [ ] Write tests for your proposed changes
- [ ] Make sure that existing tests do not fail

src/api/structure/fixture.ts

@@ -28,7 +28,7 @@ export default class Fixture extends TestingUnit {
     public globalBeforeFn: Function | null;
     public globalAfterFn: Function | null;
 
-    public constructor (testFile: TestFile, baseUrl?: string) {
+    public constructor (testFile: TestFile, baseUrl?: string, returnApiOrigin = true) {
         const pageUrl = baseUrl || SPECIAL_BLANK_PAGE;
 
         super(testFile, UnitType.fixture, pageUrl, baseUrl);
@@ -41,15 +41,12 @@ export default class Fixture extends TestingUnit {
         this.globalBeforeFn = null;
         this.globalAfterFn  = null;
 
-        return this.apiOrigin as unknown as Fixture;
+        if (returnApiOrigin)
+            return this.apiOrigin as unknown as Fixture;
     }
 
-    public static init (initOptions: FixtureInitOptions, name: string, ...rest: unknown[]): Fixture | null {
-        const { testFile, baseUrl } = initOptions;
-
-        const fixture = new Fixture(testFile, baseUrl);
-
-        return (fixture as unknown as Function)(name, ...rest);
+    public static init ({ testFile, baseUrl }: FixtureInitOptions): Fixture {
+        return super.init(Fixture, testFile, baseUrl) as unknown as Fixture;
     }
 
     protected _add (name: string, ...rest: unknown[]): Function {

src/api/structure/test.ts

@@ -34,7 +34,7 @@ export default class Test extends TestingUnit {
     private readonly _isCompilerService: boolean;
     public readonly esmRuntime: string;
 
-    public constructor (testFile: TestFile, isCompilerServiceMode = false, baseUrl?: string) {
+    public constructor (testFile: TestFile, isCompilerServiceMode = false, baseUrl?: string, returnApiOrigin = true) {
         // NOTE: 'fixture' directive can be missing
         const fixture = testFile.currentFixture as Fixture;
         const pageUrl = fixture?.pageUrl || SPECIAL_BLANK_PAGE;
@@ -57,15 +57,12 @@ export default class Test extends TestingUnit {
         // @ts-ignore
         this.esmRuntime = global[ESM_RUNTIME_HOLDER_NAME] || null;
 
-        return this.apiOrigin as unknown as Test;
+        if (returnApiOrigin)
+            return this.apiOrigin as unknown as Test;
     }
 
-    public static init (initOptions: TestInitOptions, name: string, fn: Function): Test {
-        const { testFile, baseUrl, isCompilerServiceMode } = initOptions;
-
-        const test = new Test(testFile, isCompilerServiceMode, baseUrl);
-
-        return (test as unknown as Function)(name, fn);
+    public static init ({ testFile, baseUrl, isCompilerServiceMode }: TestInitOptions): Test {
+        return TestingUnit.init(Test, testFile, isCompilerServiceMode, baseUrl) as unknown as Test;
     }
 
     private _initFixture (testFile: TestFile): void {

src/api/structure/testing-unit.ts

@@ -155,6 +155,25 @@ export default abstract class TestingUnit extends BaseUnit {
         //@ts-ignore
         ChildClass.API_LIST = TestingUnit.API_LIST.concat(getDelegatedAPIList(ChildClass.prototype));
     }
+
+    public static init (ChildClass: unknown, ...initProps: unknown[]): TestingUnit {
+        const fn = (...args: unknown[]) : unknown => {
+            //@ts-ignore
+            const apiOrigin = new ChildClass(...initProps) as unknown as Function;
+
+            return apiOrigin(...args);
+        };
+
+        const getHandler = (): unknown => {
+            //@ts-ignore
+            return new ChildClass(...initProps, false);
+        };
+
+        //@ts-ignore
+        delegateAPI(fn, ChildClass.API_LIST, { getHandler });
+
+        return fn as unknown as TestingUnit;
+    }
 }
 
 // @ts-ignore

src/compiler/test-file/add-export-api.ts

@@ -8,12 +8,12 @@ export default function (testFile: TestFile, exportableLibExports: any, {
     baseUrl,
 }: OptionalCompilerArguments = {}): void {
     Object.defineProperty(exportableLibExports, 'fixture', {
-        get:          () => Fixture.init.bind(Fixture, { testFile, baseUrl }),
+        get:          () => Fixture.init({ testFile, baseUrl }),
         configurable: true,
     });
 
     Object.defineProperty(exportableLibExports, 'test', {
-        get:          () => Test.init.bind(Test, { testFile, isCompilerServiceMode, baseUrl }),
+        get:          () => Test.init({ testFile, isCompilerServiceMode, baseUrl }),
         configurable: true,
     });
 }

test/functional/fixtures/regression/gh-7482/test.js

@@ -0,0 +1,5 @@
+describe('[Regression](GH-7482)', () => {
+    it("Shouldn't throw errors if test and fixtures methods are executed before test and fixtures", async () => {
+        return runTests('./testcafe-fixtures/index.js', '', { only: ['chrome'] });
+    });
+});

test/functional/fixtures/regression/gh-7482/testcafe-fixtures/index.js

@@ -0,0 +1,5 @@
+fixture.meta('dev', 'true')('Fixture');
+
+test.meta('dev', 'true')('Test', async t => {
+    await t.expect(true).ok();
+});