ts-jest: Unable to require `.d.ts` file on Unix only

Issue :

Similar but not the same as #950.

Running tests on my TypeScript project, including a TypeScript dependency, succeeds on Windows. It fails on Linux and OSX with the following:

 FAIL  src/__tests__/storyshots.test.ts
  ● Test suite failed to run

    TypeError: Unable to require `.d.ts` file.
    This is usually the result of a faulty configuration or import. Make sure there is a `.js`, `.json` or another executable extension available alongside `Fields.ts`.

      at getOutput (../node_modules/ts-jest/dist/compiler.js:163:23)
      at Object.compile (../node_modules/ts-jest/dist/compiler.js:185:29)
      at TsJestTransformer.process (../node_modules/ts-jest/dist/ts-jest-transformer.js:101:41)
      at Object.<anonymous> (../node_modules/@adm/webpart-library/src/Types.ts:1:1)

Fields.ts contains:

• An interface
• A type
• A function

All of which are exported.

Here is my jest.config.json:

{
  "preset": "@voitanos/jest-preset-spfx-react16",
  "rootDir": "../src",
  "reporters": ["default", "jest-junit"],
  "coverageReporters": ["cobertura", "html"],
  "collectCoverageFrom": ["**/*.{js,jsx,ts,tsx}", "!**/node_modules/**"],
  "moduleNameMapper": {
    "\\.(css|scss)$": "identity-obj-proxy",
    "^resx-strings/en-us.json": "<rootDir>/node_modules/@microsoft/sp-core-library/lib/resx-strings/en-us.json",
    "^office-ui-fabric-react/lib/(.*)$": "office-ui-fabric-react/lib-commonjs/$1",
    "^@adm/(.*)/lib/(.*)$": "@adm/$1/src/$2",
    "^@adm\/([^\/]*)$": "@adm/$1/src",
    "telemetry": "identity-obj-proxy",
    "PeopleSearchService": "identity-obj-proxy"
  },
  "transformIgnorePatterns": [
    "node_modules/(?!@adm/)"
  ]
}

(Link to preset)

Expected behavior :

The test succeeds regardless of operating system.

Debug log:

ts-jest.log

Minimal repo :

Very sorry but I do not have time to set one of these up right now. I will try and find the time to get a repo set up as soon as I can.

I am using TS 3.5, NodeJS 8.10.0/10.16.x (tried both), Jest 24.9 and ts-jest 24.0.2.