improve "preset not found" error message

[ranyitz]

Summary

After the discussion on #6538

This PR adds a descriptive error message for a case when preset module exists but doesn't have jest-preset.js or jest-preset.json files at the root

Test plan

Add a test case for it in normalize.test.js

[codecov-io]

Codecov Report

Merging #6863 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #6863      +/-   ##
==========================================
+ Coverage   66.97%   66.98%   +<.01%     
==========================================
  Files         250      250              
  Lines       10355    10358       +3     
  Branches        3        3              
==========================================
+ Hits         6935     6938       +3     
  Misses       3419     3419              
  Partials        1        1

Impacted Files	Coverage Δ
packages/jest-config/src/normalize.js	91.43% <100%> (+0.1%)	⬆️

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[SimenB]

Mind rebasing? :)

[kristianmandrup]

I'm still having major issues trying to use the default preset

$ cat ./node_modules/ts-jest/jest-preset.js 
module.exports = require('./presets/default/jest-preset')

My jest.config.js in same directory

module.exports = {
  preset: './node_modules/ts-jest/jest-preset.js',
  testEnvironment: 'node'
};

Tried this before, generated as per config:init option

module.exports = {
  preset: 'ts-jest',
  testEnvironment: 'node'
};

$ jest
Validation Error:

  Preset ts-jest not found.

But it is right there

$ cat ./node_modules/ts-jest/presets/default/jest-preset.js 
module.exports = require('..').defaults

Note: Created my project via typescript-starter and tried to switch from ava to jest but have not been able to just yet. Config nightmare still!!

My package dependencies

"dependencies": {
    "sha.js": "^2.4.11",
    "@types/jest": "^23.3.9" 
  },
  "devDependencies": {
    "codecov": "^3.1.0",
    "cz-conventional-changelog": "^2.1.0",
    "gh-pages": "^2.0.0",
    "npm-run-all": "^4.1.3",
    "nyc": "^13.0.1",
    "opn-cli": "^3.1.0",
    "prettier": "^1.14.3",
    "standard-version": "^4.4.0",
    "trash-cli": "^1.4.0",
    "ts-jest": "^23.10.5",
    "tslint": "^5.11.0",
    "tslint-config-prettier": "^1.15.0",
    "tslint-immutable": "^4.7.0",
    "typedoc": "^0.13.0",
    "typescript": "^3.0.3"
  },
 

Thanks

[kristianmandrup]

Would be helpful if the error message also returned the absolute path of the require so as to make it a bit easier to debug. Thanks

[kristianmandrup]

Finally got it working, using a hardcoded config.

module.exports = {
  "roots": [
    "<rootDir>/src"
  ],
  "transform": {
    "^.+\\.tsx?$": "ts-jest"
  },
  "testRegex": "(/__tests__/.*|(\\.|/)(test|spec))\\.tsx?$",
  "moduleFileExtensions": [
    "ts",
    "tsx",
    "js",
    "jsx",
    "json",
    "node"
  ],
}

[SimenB]

It worked for me (at least using yarn).

$ npx typescript-starter # chose hello as name, using yarn and a node project
$ cd hello
$ yarn add -D jest ts-jest @types/jest
$ yarn ts-jest config:init
$ yarn jest
Test Suites: 3 failed, 3 total
Tests:       0 total
Snapshots:   0 total
Time:        2.787s
Ran all test suites.

Tests failed with either being unable to find ava or missing type annotations on the t callback, both expected. Can run jest-codemods to transform the tests.

@kristianmandrup can you provide a reproduction?

[github-actions]

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