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Jest ecountered transfomer error after jest.config.ts was moved to a different folder
My initial project structure was:
.
|--src
|  |--component1
|  |  |--service1.ts
|  |--component2
|  |  |--service2.ts
|  |--tests
|  |  |--service1.test.ts
|  |  |--service2.test.ts
|--dist
|--jest.config.ts
|--tsconfig.json
|--package.json

tsconfig.json had the following contents
{
  "extends": "../tsconfig.json",
  "exclude": ["src/test/*.test.ts"],
  "compilerOptions": {
    "rootDir": ".",
    "outDir": "dist",
    "typeRoots": ["node_modules/@types"]
  }
}

jest.config.ts had the following contents
import type { JestConfigWithTsJest } from 'ts-jest'

const jestConfig: JestConfigWithTsJest = {
  verbose: true,
  preset: 'ts-jest',
  testEnvironment: 'node',
}

export default jestConfig

With the configuration, i was able to run the tests successfully but deployment was all screwed up because of "rootDir": "." (it was previously "rootDir": "src").
So, I ended up moving jest.config.ts inside the src folder like so
.
|--src
|  |--component1
|  |  |--service1.ts
|  |--component2
|  |  |--service2.ts
|  |--tests
|  |  |--service1.test.ts
|  |  |--service2.test.ts
|  |--jest.config.ts
|--dist    
|--tsconfig.json
|--package.json

Now, the tests do not work :-( I get the error below
 FAIL  src/test/webhook.test.ts
  ● Test suite failed to run

    Jest encountered an unexpected token

    Jest failed to parse a file. This happens e.g. when your code or its dependencies use non-standard JavaScript syntax, or when Jest is not c

    Out of the box Jest supports Babel, which will be used to transform your files into valid JS based on your Babel configuration.

    By default "node_modules" folder is ignored by transformers.

    Here's what you can do:
     • If you are trying to use ECMAScript Modules, see https://jestjs.io/docs/ecmascript-modules for how to enable it.
     • If you are trying to use TypeScript, see https://jestjs.io/docs/getting-started#using-typescript
     • To have some of your "node_modules" files transformed, you can specify a custom "transformIgnorePatterns" in your config.
     • If you need a custom transformation specify a "transform" option in your config.
     • If you simply want to mock your non-JS modules (e.g. binary assets) you can stub them out with the "moduleNameMapper" config option.

    You'll find more details and examples of these config options in the docs:
    https://jestjs.io/docs/configuration
    For information about custom transformations, see:
    https://jestjs.io/docs/code-transformation

    Details:

    SyntaxError: C:\Users\acddc\Documents\GitHub\cdcdc\cdcdc\cdcd\src\test\webhook.test.ts: Missing initializer in co

      42 | test('Good case: Check service bus message', async () => {
      43 |   // Arrange
    > 44 |   const context: Context = {
         |                ^
      45 |     log: {
      46 |       info: jest.fn(),
      47 |     },

      at instantiate (node_modules/@babel/parser/src/parse-error/credentials.ts:62:21)
      at instantiate (node_modules/@babel/parser/src/parse-error.ts:60:12)
      at Parser.toParseError [as raise] (node_modules/@babel/parser/src/tokenizer/index.ts:1474:19)
      at Parser.raise [as parseVar] (node_modules/@babel/parser/src/parser/statement.ts:1507:16)
      at Parser.parseVar [as parseVarStatement] (node_modules/@babel/parser/src/parser/statement.ts:1152:10)
      at Parser.parseVarStatement [as parseStatementContent] (node_modules/@babel/parser/src/parser/statement.ts:538:21)
      at Parser.parseStatementContent [as parseStatementLike] (node_modules/@babel/parser/src/parser/statement.ts:420:17)
      at Parser.parseStatementLike [as parseStatementListItem] (node_modules/@babel/parser/src/parser/statement.ts:375:17)
      at Parser.parseStatementListItem [as parseBlockOrModuleBlockBody] (node_modules/@babel/parser/src/parser/statement.ts:1346:16)
      at Parser.parseBlockOrModuleBlockBody [as parseBlockBody] (node_modules/@babel/parser/src/parser/statement.ts:1319:10)
      at Parser.parseBlockBody [as parseBlock] (node_modules/@babel/parser/src/parser/statement.ts:1287:10)
      at Parser.parseBlock [as parseFunctionBody] (node_modules/@babel/parser/src/parser/expression.ts:2559:24)
      at Parser.parseFunctionBody [as parseArrowExpression] (node_modules/@babel/parser/src/parser/expression.ts:2502:10)
      at Parser.parseArrowExpression [as parseAsyncArrowFromCallExpression] (node_modules/@babel/parser/src/parser/expression.ts:1063:10)
      at Parser.parseAsyncArrowFromCallExpression [as parseCoverCallAndAsyncArrowHead] (node_modules/@babel/parser/src/parser/expression.ts:916
      at Parser.parseCoverCallAndAsyncArrowHead [as parseSubscript] (node_modules/@babel/parser/src/parser/expression.ts:782:19)
      at Parser.parseSubscript [as parseSubscripts] (node_modules/@babel/parser/src/parser/expression.ts:743:19)
      at Parser.parseSubscripts [as parseExprSubscripts] (node_modules/@babel/parser/src/parser/expression.ts:728:17)
      at Parser.parseExprSubscripts [as parseUpdate] (node_modules/@babel/parser/src/parser/expression.ts:699:21)
      at Parser.parseUpdate [as parseMaybeUnary] (node_modules/@babel/parser/src/parser/expression.ts:661:23)
      at Parser.parseMaybeUnary [as parseMaybeUnaryOrPrivate] (node_modules/@babel/parser/src/parser/expression.ts:399:14)
      at Parser.parseMaybeUnaryOrPrivate [as parseExprOps] (node_modules/@babel/parser/src/parser/expression.ts:411:23)
      at Parser.parseExprOps [as parseMaybeConditional] (node_modules/@babel/parser/src/parser/expression.ts:366:23)
      at Parser.parseMaybeConditional [as parseMaybeAssign] (node_modules/@babel/parser/src/parser/expression.ts:306:21)
      at parseMaybeAssign (node_modules/@babel/parser/src/parser/expression.ts:260:12)
      at Parser.callback [as allowInAnd] (node_modules/@babel/parser/src/parser/expression.ts:3085:12)
      at Parser.allowInAnd [as parseMaybeAssignAllowIn] (node_modules/@babel/parser/src/parser/expression.ts:259:17)
      at Parser.parseMaybeAssignAllowIn [as parseExprListItem] (node_modules/@babel/parser/src/parser/expression.ts:2721:18)
      at Parser.parseExprListItem [as parseCallExpressionArguments] (node_modules/@babel/parser/src/parser/expression.ts:1043:14)
      at Parser.parseCallExpressionArguments [as parseCoverCallAndAsyncArrowHead] (node_modules/@babel/parser/src/parser/expression.ts:893:29)
      at Parser.parseCoverCallAndAsyncArrowHead [as parseSubscript] (node_modules/@babel/parser/src/parser/expression.ts:782:19)
      at Parser.parseSubscript [as parseSubscripts] (node_modules/@babel/parser/src/parser/expression.ts:743:19)
      at Parser.parseSubscripts [as parseExprSubscripts] (node_modules/@babel/parser/src/parser/expression.ts:728:17)
      at Parser.parseExprSubscripts [as parseUpdate] (node_modules/@babel/parser/src/parser/expression.ts:699:21)
      at Parser.parseUpdate [as parseMaybeUnary] (node_modules/@babel/parser/src/parser/expression.ts:661:23)
      at Parser.parseMaybeUnary [as parseMaybeUnaryOrPrivate] (node_modules/@babel/parser/src/parser/expression.ts:399:14)
      at Parser.parseMaybeUnaryOrPrivate [as parseExprOps] (node_modules/@babel/parser/src/parser/expression.ts:411:23)
      at Parser.parseExprOps [as parseMaybeConditional] (node_modules/@babel/parser/src/parser/expression.ts:366:23)
      at Parser.parseMaybeConditional [as parseMaybeAssign] (node_modules/@babel/parser/src/parser/expression.ts:306:21)
      at Parser.parseMaybeAssign [as parseExpressionBase] (node_modules/@babel/parser/src/parser/expression.ts:229:23)
      at parseExpressionBase (node_modules/@babel/parser/src/parser/expression.ts:220:39)
      at Parser.callback [as allowInAnd] (node_modules/@babel/parser/src/parser/expression.ts:3080:16)
      at Parser.allowInAnd [as parseExpression] (node_modules/@babel/parser/src/parser/expression.ts:220:17)
      at Parser.parseExpression [as parseStatementContent] (node_modules/@babel/parser/src/parser/statement.ts:629:23)
      at Parser.parseStatementContent [as parseStatementLike] (node_modules/@babel/parser/src/parser/statement.ts:420:17)
          at parser.next (<anonymous>)
      at normalizeFile (node_modules/@babel/core/src/transformation/normalize-file.ts:52:24)
          at normalizeFile.next (<anonymous>)
      at run (node_modules/@babel/core/src/transformation/index.ts:38:36)
          at run.next (<anonymous>)
      at transform (node_modules/@babel/core/src/transform.ts:29:20)
          at transform.next (<anonymous>)
      at evaluateSync (node_modules/gensync/index.js:251:28)
m/build/ScriptTransformer.js:519:31)
      at ScriptTransformer._transformAndBuildScript (node_modules/@jest/transform/build/ScriptTransformer.js:648:40)
      at ScriptTransformer.transform (node_modules/@jest/transform/build/ScriptTransformer.js:700:19)

Test Suites: 1 failed, 1 total
Tests:       0 total
Snapshots:   0 total
Time:        2.431 s
Ran all test suites.

I tried to follow the suggestion given in the question(SOquestion) and change the jest.config.ts to as below but that did not work either.
import type { JestConfigWithTsJest } from 'ts-jest'

const jestConfig: JestConfigWithTsJest = {
  verbose: true,
  preset: 'ts-jest',
  testMatch: ['./test/*'],
  extensionsToTreatAsEsm: ['.ts'],
  globals: {
    'ts-jest': {
      useESM: true,
    },
  },
}

export default jestConfig

How do I resolve this issue with the constraint that I cannot change the tsconfig.json. Please guide.

All I had to do was change "exclude": ["src/test/*.test.ts"], to "include": ["src/test/*.test.ts"], in the tsconfig.json file!
Update
The above solution screwed my dist folder & hence unusable.
I ended up following the solution suggested here (creating a separate tsconfig file just foe testing)
Why isn't ts-jest loading my custom tsconfig file?
