expect/jest-matcher-utils: Improve report when assertion fails, part 5

[pedrottimark]

Summary

Goal: people can quickly see information that is relevant to them

To replace redundant descriptions, and be consistent with stack frame, format as regular black:

• promise resolves or rejects
• not
• matcher name

Added promise property to this of matcher methods and to options object argument of matcherHint function.

For backward compatibility of community matchers and so we can update snapshots in batches, remove period from matcher name to enable the improvement. For example, replace '.toBeDefined' with 'toBeDefined' in first argument of matcherHint function call.

Test plan

The change column in the following table refers to one or more of the following:

• omit extra escape sequences to close and reopen dim gray color of closing paren when matcher has no expected value
• matcher name in regular black instead of dim gray color
• lowercase promise to omit unnecessary case distinction in error message
• separate description of why assertion failed from the received value

	module	file	tests	change
1	expect	assertionCounts		expected
50	expect	spyMatchers		expected
2	expect	toThrowMatchers		expected
26	expect	matchers	resolves and rejects	expected, name, promise, separate
20	expect	matchers	toBeDefined and toBeUndefined	expected, name
32	expect	matchers	toBeFalsy and toBeTruthy	expected, name
14	expect	matchers	toBeNaN	expected, name
10	expect	matchers	toBeNull	expected, name; also corrected test string
2	jest-matcher-utils	index	ensureNoExpected	replace obsolete test with relevant test
1	e2e	failures	async	separate

See also pictures in following comment

Fixes #7105

[pedrottimark]

Pictures of improved at right in which assertion line is clear and consistent with stack frame.

When received value is incorrect according to matcher criterion:

When received value must be a promise:

When received promise rejected/resolved instead of resolved/rejected

Updated the following picture according to #7557 (comment)

When matcher must not have an expected argument:

Updated the following picture according to #7557 (comment)

[codecov-io]

Codecov Report

Merging #7557 into master will increase coverage by 0.06%.
The diff coverage is 93.33%.

@@            Coverage Diff             @@
##           master    #7557      +/-   ##
==========================================
+ Coverage   67.99%   68.06%   +0.06%     
==========================================
  Files         248      248              
  Lines        9490     9522      +32     
  Branches        6        5       -1     
==========================================
+ Hits         6453     6481      +28     
- Misses       3035     3039       +4     
  Partials        2        2

Impacted Files	Coverage Δ
packages/expect/src/matchers.js	99.43% <100%> (+0.01%)	⬆️
packages/expect/src/index.js	93.96% <100%> (ø)	⬆️
packages/jest-matcher-utils/src/index.js	94.73% <86.66%> (-5.27%)	⬇️

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[thymikee]

When expected value must be omitted or undefined

I know this is behavior that we have currently, but using "expected" there seems out of place, because there's no such in the matcher hint. How about just using the "received" as in improved messages for resolves/rejects matchers?

[pedrottimark]

Your second pair of eyes is always helpful. Yes, I agree that hint and message don’t add up.

Here is a picture with expected in the matcher hint only for this error message:

I’m not sure if I understood the alternative htat you meant. Can you say it in other words?

I will let it marinate in my mind whether there is another way to communicate the problem.

[thymikee]

I was thinking about:

Matcher error: received value must be omitted or undefined

Received has value: null

Does that sound right? It seems on pair with the new promise-related messages.

Here is a picture with expected in the matcher hint only for this error message:

Pretty sure adding the "expected" as an argument of argument-less fn is pretty confusing as well.

[pedrottimark]

Received seems like it applies to an incorrect assertion like expect(null).hasAssertions()

What do you think about the phrase expected argument in black?

[thymikee]

Sounds good 👍

[thymikee]

A jest-circus test timing out indicates a slowdown in execution. Worth investigating. I've re-run it 2 times just be sure, still failing.

[pedrottimark]

Yeah, some of the CI results have been a puzzle to me.

• When node 10 failed, I merged some changes from master, and then jest-test-circus failed.
• After merging most recent changes from master, now they both pass.

[thymikee]

@SimenB can you have a final look? I think it's good to merge now

[github-actions]

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