diff --git a/scripts/tests.js b/scripts/tests.js
index 2bd482195c..a06cdf7bb3 100644
--- a/scripts/tests.js
+++ b/scripts/tests.js
@@ -13,11 +13,19 @@ function getDirectories(rootDir) {
   });
 }
 
+function isJestFolder(basename) {
+  return basename.startsWith('__') && basename.endsWith('__');
+}
+
+// TODO: later we could add a `.test-case-keep` empty file in each folder?
+// ...or move all into a `test-cases` dedicated directory
+function isTestCaseFolder(basename) {
+  return !isJestFolder(basename);
+}
+
 function createIntegrationMock() {
   const testsRoot = 'tests';
-  const testCaseFolders = getDirectories(testsRoot).filter(function(testDir) {
-    return !/^(?:utils|__.+__)$/.test(testDir);
-  });
+  const testCaseFolders = getDirectories(testsRoot).filter(isTestCaseFolder);
 
   testCaseFolders.forEach(directory => {
     const testCaseNodeModules = path.join(testsRoot, directory, 'node_modules');
@@ -41,9 +49,6 @@ function createIntegrationMock() {
 
 createIntegrationMock();
 
-// HACK: allow us to change the `startDir()` during tests
-process.env.__RUNNING_TS_JEST_TESTS = Date.now();
-
 const argv = process.argv.slice(2);
 argv.push('--no-cache');
 argv.push('--testPathPattern', '^(?!(.*watch.spec.ts$)).*');
diff --git a/src/preprocess.ts b/src/preprocess.ts
index 9e954bd46c..064e901001 100644
--- a/src/preprocess.ts
+++ b/src/preprocess.ts
@@ -22,7 +22,11 @@ export default function preprocess(
   const isHtmlFile = /\.html$/.test(filePath);
 
   // This is to support angular 2. See https://github.com/kulshekhar/ts-jest/pull/145
-  if (isHtmlFile && (jestConfig.globals as any).__TRANSFORM_HTML__) {
+  if (
+    isHtmlFile &&
+    jestConfig.globals &&
+    (jestConfig.globals as any).__TRANSFORM_HTML__
+  ) {
     src = 'module.exports=' + JSON.stringify(src) + ';';
   }
 
diff --git a/src/utils/get-ts-config.ts b/src/utils/get-ts-config.ts
index c556a4112e..6c018303ed 100644
--- a/src/utils/get-ts-config.ts
+++ b/src/utils/get-ts-config.ts
@@ -95,19 +95,6 @@ function readCompilerOptions(configPath: string): CompilerOptions {
   return options;
 }
 
-// function getStartDir(jestConfig: jest.ProjectConfig): string {
-//   // This is needed because of the way our tests are structured.
-//   // If this is being executed as a library (under node_modules)
-//   // we want to start with the project directory that's three
-//   // levels above.
-//   // If this is being executed from the test suite, we want to start
-//   // in the directory of the test
-
-//   // TODO: shouldn't we use the path of jest config here instead of '.' ?
-//   // return process.env.__RUNNING_TS_JEST_TESTS ? process.cwd() : '.';
-//   return process.env.__RUNNING_TS_JEST_TESTS ? process.cwd() : (jestConfig.rootDir || process.cwd());
-// }
-
 // we don't need any data, just its full path
 const tsConfigReader = { basename: TSCONFIG_FILENAME, read: () => 0 };
 
diff --git a/tests/__helpers__/jest-config.ts b/tests/__helpers__/jest-config.ts
deleted file mode 100644
index 61b8c7bcff..0000000000
--- a/tests/__helpers__/jest-config.ts
+++ /dev/null
@@ -1,210 +0,0 @@
-import { TsJestConfig } from '../../dist/types';
-
-const { resolve } = require.requireActual('path');
-
-function createJestConfig(
-  testModulePath: string,
-  tsJestOptions: TsJestConfig | null = null,
-  jestOptions: jest.InitialOptions = {},
-): jest.ProjectConfig {
-  const rootDir = resolve(__dirname, '..', testModulePath);
-  let options = { ...jestOptions };
-  if (tsJestOptions)
-    options.globals = { ...options.globals, 'ts-jest': tsJestOptions };
-  return { rootDir, cwd: rootDir, ...options } as any;
-}
-require('fs').read;
-const jestConfig = Object.assign(createJestConfig, {
-  babelConfig: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('babel-config', t, j),
-  babelConfigInvalid: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('babel-config-invalid', t, j),
-  babelConfigMergeIgnoreBabelrc: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => createJestConfig('babel-config-merge-ignore-babelrc', t, j),
-  babelConfigMergeWithBabelrc: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => createJestConfig('babel-config-merge-with-babelrc', t, j),
-  button: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('button', t, j),
-  dynamicImports: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('dynamic-imports', t, j),
-  hoistErrors: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('hoist-errors', t, j),
-  hoistTest: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('hoist-test', t, j),
-  importsTest: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('imports-test', t, j),
-  jestProjects: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('jest-projects', t, j),
-  jestProjectsWithWorkspace: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => createJestConfig('jest-projects-with-workspace', t, j),
-  jestconfigTest: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('jestconfig-test', t, j),
-  metadataEmit: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('metadata-emit', t, j),
-  noJsonModuleFileExt: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('no-json-module-file-ext', t, j),
-  noSourcemaps: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('no-sourcemaps', t, j),
-  noSyntheticDefault: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('no-synthetic-default', t, j),
-  simple: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('simple', t, j),
-  simpleAsync: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('simple-async', t, j),
-  simpleLongPath: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('simple-long-path', t, j),
-  skipBabelrc: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('skip-babelrc', t, j),
-  syntheticDefault: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('synthetic-default', t, j),
-  tsDiagnostics: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('ts-diagnostics', t, j),
-  tsJestModuleInterface: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('ts-jest-module-interface', t, j),
-  tsconfigTest: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('tsconfig-test', t, j),
-  useBabelrc: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('use-babelrc', t, j),
-  useConfigFromNodeModules: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => createJestConfig('use-config-from-node-modules', t, j),
-  useStrict: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('use-strict', t, j),
-  utils: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('utils', t, j),
-  watchTest: (t?: TsJestConfig | null, j?: jest.InitialOptions) =>
-    createJestConfig('watch-test', t, j),
-});
-
-interface TestJestConfigHelpers {
-  (
-    testModulePath: string,
-    tsJestOptions?: TsJestConfig | null,
-    jestOptions?: jest.InitialOptions,
-  ): jest.ProjectConfig;
-  babelConfig: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  babelConfigInvalid: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  babelConfigMergeIgnoreBabelrc: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  babelConfigMergeWithBabelrc: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  button: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  dynamicImports: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  hoistErrors: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  hoistTest: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  importsTest: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  jestProjects: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  jestProjectsWithWorkspace: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  jestconfigTest: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  metadataEmit: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  noJsonModuleFileExt: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  noSourcemaps: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  noSyntheticDefault: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  simple: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  simpleAsync: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  simpleLongPath: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  skipBabelrc: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  syntheticDefault: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  tsDiagnostics: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  tsJestModuleInterface: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  tsconfigTest: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  useBabelrc: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  useConfigFromNodeModules: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  useStrict: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  utils: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-  watchTest: (
-    t?: TsJestConfig | null,
-    j?: jest.InitialOptions,
-  ) => jest.ProjectConfig;
-}
-
-export default jestConfig as TestJestConfigHelpers;
diff --git a/tests/__helpers__/mock-jest-config.ts b/tests/__helpers__/mock-jest-config.ts
new file mode 100644
index 0000000000..8981a549ad
--- /dev/null
+++ b/tests/__helpers__/mock-jest-config.ts
@@ -0,0 +1,26 @@
+import { TsJestConfig } from '../../dist/types';
+
+const { resolve } = require.requireActual('path');
+
+/**
+ * Mock a jest config object for the test case in given folder
+ *
+ * Basically it defines `rootDir` and `cwd` properties to the full path of that
+ * test case, as Jest would do.
+ *
+ * Accepts an optional config object, which will be defined on `globals.ts-jest`
+ */
+export default function mockJestConfig(
+  testCaseFolder: string,
+  tsJest: TsJestConfig | null = null,
+): jest.ProjectConfig {
+  // resolves the path since jest would give a resolved path
+  const rootDir = resolve(__dirname, '..', testCaseFolder);
+  // create base jest config object
+  let options: any = { rootDir, cwd: rootDir };
+  // adds TS Jest options if any given
+  if (tsJest != null) {
+    options.globals = { 'ts-jest': tsJest };
+  }
+  return options;
+}
diff --git a/tests/__tests__/get-cache-key.spec.ts b/tests/__tests__/get-cache-key.spec.ts
index 9fff410267..d71ccab5b6 100644
--- a/tests/__tests__/get-cache-key.spec.ts
+++ b/tests/__tests__/get-cache-key.spec.ts
@@ -1,5 +1,5 @@
 import getCacheKey from '../../dist/utils/get-cache-key';
-import cfg from '../__helpers__/jest-config';
+import mockJestConfig from '../__helpers__/mock-jest-config';
 import _getTSConfig from '../../dist/utils/get-ts-config';
 
 jest.mock('../../dist/utils/get-ts-config', () => {
@@ -13,10 +13,11 @@ const getTSConfig: jest.Mock = _getTSConfig as any;
 
 describe('getCacheKey', () => {
   const src = 'console.log(123);';
-  const jestConfig = cfg.simple(null, {
+  const jestConfig = {
+    ...mockJestConfig('simple'),
     transform: { '^.+\\\\.tsx?$': '../../preprocessor.js' },
     testRegex: '(/__tests__/.*|(\\\\.|/)(test|spec))\\\\.(jsx?|tsx?)$',
-  });
+  };
   const filepath = `${jestConfig.rootDir}/some-file.ts`;
   const configStr = JSON.stringify(jestConfig);
   const options = { instrument: false, rootDir: jestConfig.rootDir };
diff --git a/tests/__tests__/html-transform.spec.ts b/tests/__tests__/html-transform.spec.ts
index 718b5f797a..b25d88fa1c 100644
--- a/tests/__tests__/html-transform.spec.ts
+++ b/tests/__tests__/html-transform.spec.ts
@@ -1,32 +1,47 @@
 import * as tsJest from '../../dist';
-import jestConfig from '../__helpers__/jest-config';
+import mockJestConfig from '../__helpers__/mock-jest-config';
 
-const config = jestConfig.simple({});
-const filePath = `${config.rootDir}/some-file.html`;
+const TEST_CASE = 'simple';
+const FILENAME = 'some-file.html';
 
-// wrap a transformed source so that we can fake a `require()` on it by calling the returned wrapper
-const wrap = (src: string) =>
-  new Function(`var module={}; ${src} return module.exports;`) as any;
-
-const source = `<div class="html-test">
+const fileContent = `<div class="html-test">
   <span class="html-test__element">This is element</span>
   <code>This is a backtilt \`</code>
 </div>`;
 
 describe('Html transforms', () => {
   it('transforms html if config.globals.__TRANSFORM_HTML__ is set', () => {
+    let jestConfig;
+
     // get the untransformed version
-    const untransformed = tsJest.process(source, filePath, { ...config });
-    // ... then the one which should be transformed
-    (config.globals as any).__TRANSFORM_HTML__ = true;
-    const transformed = tsJest.process(source, filePath, config) as string;
-    // ... finally the result of a `require('module-with-transformed-version')`
-    const exported = wrap(transformed)();
+    jestConfig = mockJestConfig(TEST_CASE);
+    const untransformed = tsJest.process(
+      fileContent,
+      `${jestConfig.rootDir}/${FILENAME}`,
+      jestConfig,
+    );
+    expect(untransformed).toBe(fileContent);
+    expect(untransformed).toMatchSnapshot('untransformed');
 
-    expect(exported).toMatchSnapshot('module');
+    // ... then the one which should be transformed
+    jestConfig = {
+      ...mockJestConfig(TEST_CASE),
+      globals: { __TRANSFORM_HTML__: true },
+    };
+    const transformed = tsJest.process(
+      fileContent,
+      `${jestConfig.rootDir}/${FILENAME}`,
+      jestConfig,
+    ) as string;
+    expect(transformed).not.toBe(fileContent);
     expect(transformed).toMatchSnapshot('source');
-    expect(untransformed).toMatchSnapshot('untransformed');
-    // requiring the transformed version should return the same string as the untransformed version
-    expect(exported).toBe(untransformed);
+
+    // ... finally the result of a `require('module-with-transformed-version')`
+    const value = eval(
+      `(function(){const module={}; ${transformed}; return module.exports;})()`,
+    );
+    expect(value).toMatchSnapshot('module');
+    // the value should be the same string as the source version
+    expect(value).toBe(fileContent);
   });
 });
diff --git a/tests/__tests__/postprocess.spec.ts b/tests/__tests__/postprocess.spec.ts
index 74792d0ac2..8e03b265a0 100644
--- a/tests/__tests__/postprocess.spec.ts
+++ b/tests/__tests__/postprocess.spec.ts
@@ -7,7 +7,7 @@ jest.mock('@babel/core', () => {
 });
 
 import { getPostProcessHook } from '../../dist/postprocess';
-import jestConfig from '../__helpers__/jest-config';
+import mockJestConfig from '../__helpers__/mock-jest-config';
 
 describe('postprocess', () => {
   function runHook(jestConfig = {} as any) {
@@ -32,7 +32,7 @@ describe('postprocess', () => {
     const transformMock = require.requireMock('@babel/core').transform;
 
     runHook();
-    getPostProcessHook(jestConfig.simple())(
+    getPostProcessHook(mockJestConfig('simple'))(
       { code: 'input_code', map: '"input_source_map"' },
       'fake_file',
       {} as any,
diff --git a/tests/__tests__/tsconfig-comments.spec.ts b/tests/__tests__/tsconfig-comments.spec.ts
index 7479c721f6..28aa8a7f1b 100644
--- a/tests/__tests__/tsconfig-comments.spec.ts
+++ b/tests/__tests__/tsconfig-comments.spec.ts
@@ -3,7 +3,9 @@ jest.mock('path');
 import * as fs from 'fs';
 import getTSConfig from '../../dist/utils/get-ts-config';
 import * as path from 'path';
-import cfg from '../__helpers__/jest-config';
+import mockJestConfig from '../__helpers__/mock-jest-config';
+
+const TEST_CASE = 'tsconfig-test';
 
 describe('parse tsconfig with comments', () => {
   const configFile1 = './tests/tsconfig-test/allows-comments.json';
@@ -38,16 +40,16 @@ describe('parse tsconfig with comments', () => {
     // while allows-comments2.json does.
     // allow-comments.json extends allow-comments2.json
     it('should correctly read allow-comments.json', () => {
-      const config = getTSConfig(
-        cfg.tsconfigTest({ tsConfigFile: 'allows-comments.json' }),
+      const tsConfig = getTSConfig(
+        mockJestConfig(TEST_CASE, { tsConfigFile: 'allows-comments.json' }),
       );
-      expect(config).toMatchSnapshot();
+      expect(tsConfig).toMatchSnapshot();
     });
     it('should correctly read allow-comments2.json', () => {
-      const config = getTSConfig(
-        cfg.tsconfigTest({ tsConfigFile: 'allows-comments2.json' }),
+      const tsConfig = getTSConfig(
+        mockJestConfig(TEST_CASE, { tsConfigFile: 'allows-comments2.json' }),
       );
-      expect(config).toMatchSnapshot();
+      expect(tsConfig).toMatchSnapshot();
     });
   });
 });
diff --git a/tests/__tests__/tsconfig-default.spec.ts b/tests/__tests__/tsconfig-default.spec.ts
index dbfc24c89f..d9b3cae369 100644
--- a/tests/__tests__/tsconfig-default.spec.ts
+++ b/tests/__tests__/tsconfig-default.spec.ts
@@ -4,9 +4,11 @@ jest.mock('path');
 import * as ts from 'typescript';
 import getTSConfig from '../../dist/utils/get-ts-config';
 import * as path from 'path';
-import jestConfig from '../__helpers__/jest-config';
+import mockJestConfig from '../__helpers__/mock-jest-config';
 import getTSJestConfig from '../../dist/utils/get-ts-jest-config';
 
+const TEST_CASE = 'tsconfig-test';
+
 describe('get default ts config', () => {
   beforeEach(() => {
     // Set up some mocked out file info before each test
@@ -19,44 +21,46 @@ describe('get default ts config', () => {
     // there is no tsconfig file in that test module
     ((path as any) as MockedPath).__setBaseDir('./tests/jestconfig-test');
 
-    expect(() => getTSConfig(jestConfig.jestconfigTest(null))).toThrowError(
+    expect(() => getTSConfig(mockJestConfig('jestconfig-test'))).toThrowError(
       /unable to find ts configuration file/i,
     );
   });
 
   it('should correctly read tsconfig.json', () => {
-    const result = getTSConfig(jestConfig.tsconfigTest(null));
+    const result = getTSConfig(mockJestConfig(TEST_CASE));
 
     expect(result).toMatchSnapshot();
   });
 
   describe('new behavior (tsConfigFile & tsConfig)', () => {
     it('should be same results for null/undefined/etc.', () => {
-      const result = getTSConfig(jestConfig.tsconfigTest(null));
-      const resultEmptyParam = getTSConfig(jestConfig.tsconfigTest({}));
+      const resultWithoutTsJestSection = getTSConfig(
+        mockJestConfig(TEST_CASE, null),
+      );
+      const resultEmptyParam = getTSConfig(mockJestConfig(TEST_CASE, {}));
       const resultUndefinedContentFile = getTSConfig(
-        jestConfig.tsconfigTest({ tsConfigFile: undefined }),
+        mockJestConfig(TEST_CASE, { tsConfigFile: undefined }),
       );
       const resultNullContentFile = getTSConfig(
-        jestConfig.tsconfigTest({ tsConfigFile: null }),
+        mockJestConfig(TEST_CASE, { tsConfigFile: null }),
       );
 
-      expect(result).toEqual(resultEmptyParam);
-      expect(result).toEqual(resultUndefinedContentFile);
-      expect(result).toEqual(resultNullContentFile);
+      expect(resultEmptyParam).toEqual(resultWithoutTsJestSection);
+      expect(resultUndefinedContentFile).toEqual(resultWithoutTsJestSection);
+      expect(resultNullContentFile).toEqual(resultWithoutTsJestSection);
     });
 
     it('should be different results for different rootDir with same jest config.', () => {
-      const rootConfig = getTSConfig(jestConfig.tsconfigTest());
+      const rootConfig = getTSConfig(mockJestConfig(TEST_CASE));
       const subConfig = getTSConfig(
-        jestConfig('tsconfig-test/tsconfig-module'),
+        mockJestConfig(`${TEST_CASE}/tsconfig-module`),
       );
       expect(rootConfig).not.toEqual(subConfig);
     });
 
     it('should not change the module if it is loaded from a non-default config file', () => {
       const config = getTSConfig(
-        jestConfig.tsconfigTest({
+        mockJestConfig(TEST_CASE, {
           tsConfigFile: 'tsconfig-module/custom-config.json',
         }),
       );
@@ -73,7 +77,9 @@ describe('get default ts config', () => {
         './tests/tsconfig-test/tsconfig-module',
       );
 
-      const config = getTSConfig(jestConfig('tsconfig-test/tsconfig-module'));
+      const config = getTSConfig(
+        mockJestConfig(`${TEST_CASE}/tsconfig-module`),
+      );
 
       expect(config.module).toBe(ts.ModuleKind.CommonJS);
     });
diff --git a/tests/__tests__/tsconfig-string.spec.ts b/tests/__tests__/tsconfig-string.spec.ts
index 5b4285783a..2267ac95e9 100644
--- a/tests/__tests__/tsconfig-string.spec.ts
+++ b/tests/__tests__/tsconfig-string.spec.ts
@@ -3,7 +3,9 @@ jest.mock('path');
 import getTSConfig from '../../dist/utils/get-ts-config';
 import * as ts from 'typescript';
 import * as path from 'path';
-import cfg from '../__helpers__/jest-config';
+import mockJestConfig from '../__helpers__/mock-jest-config';
+
+const TEST_CASE = 'tsconfig-test';
 
 describe('get ts config from string', () => {
   beforeEach(() => {
@@ -15,7 +17,7 @@ describe('get ts config from string', () => {
   describe('new behaviour (tsConfigFile & tsConfig)', () => {
     it('should correctly read my-tsconfig.json', () => {
       const result = getTSConfig(
-        cfg.tsconfigTest({ tsConfigFile: 'my-tsconfig.json' }),
+        mockJestConfig(TEST_CASE, { tsConfigFile: 'my-tsconfig.json' }),
       );
 
       // snapshot would be enough here, but that adds a security in case we do not see it in a PR
@@ -25,7 +27,7 @@ describe('get ts config from string', () => {
 
     it('should correctly resolve the "extends" directive', () => {
       const result = getTSConfig(
-        cfg.tsconfigTest({ tsConfigFile: 'extends-tsconfig.json' }),
+        mockJestConfig(TEST_CASE, { tsConfigFile: 'extends-tsconfig.json' }),
       );
 
       // snapshot would be enough here, but that adds a security in case we do not see it in a PR
@@ -35,7 +37,7 @@ describe('get ts config from string', () => {
 
     it('should correctly override any config in the "extends" directive', () => {
       const result = getTSConfig(
-        cfg.tsconfigTest({
+        mockJestConfig(TEST_CASE, {
           tsConfigFile: 'extends-with-overrides-tsconfig.json',
         }),
       );