Fix stack trace for errors thrown by snapshot serializers

[nicolasiensen]

Summary

In this commit, we are creating a new custom error called PrettyFormatPluginError, this error is thrown by prettyFormat function when a serializer throws an error.

In the expect module, we skip Error.captureStackTrace if the error name is PrettyFormatPluginError, this way the stack trace stays intact.

Fixes #3302

Test plan

Given a test file foo.test.js:

test("should match the snapshot", () => {
  const bar = {
    foo: {
      x: 1,
      y: 2
    }
  };

  expect(bar).toMatchSnapshot();
});

And a custom snapshot serializer my-serializer-module.js

module.exports = {
  test: val => {
    throw new Error("Where is this error?");
  },
  print: val => ""
};

And a package.json:

{
  "jest": {
    "snapshotSerializers": ["./my-serializer-module"]
  }
}

When jest is run, with the current implementation, the failure message has no trace of the error thrown by the custom serializer:

With the new implementation we have a failure message that includes a trace from the error thrown by the custom serializer:

[SimenB]

I like this. Mind adding a note in the changelog?

[Nargonath]

Yeah this looks nice. Good job @nicolasiensen

[pedrottimark]

If for any reason the prettyFormat call doesn’t throw, then the test passes?

What do you think about: DISREGARD FOLLOWING CODE

let name;
try {
  prettyFormat('', options);
} catch (error) {
  name = error.name;
}
expect(name).toBe('PrettyFormatPluginError');

[SimenB]

Either do expect().toThrow() or expect.hasAssertions instead

[pedrottimark]

@SimenB Thank you! Because toThrow matches the message but the name is the test criterion, then our requested change is keep try-catch as originally written and insert expect.hasAssertions() at beginning of each of the 3 test blocks?

[SimenB]

True. Or .toThrow(PrettyFormatPluginError) if it's exported.

[pedrottimark]

Very nice. One suggestion about the 3 added tests.

[SimenB]

Triple equals?

[SimenB]

Seeing as the linter doesn't complain, maybe not needed

[SimenB]

Missing link to PR

[cpojer]

Thank you everyone for working on this PR :)

[github-actions]

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