test_runner: add mock call assertions to t.assert

[araujogui]

Adds four assertions to t.assert for checking mock function calls:

• t.assert.called(fn[, message])
• t.assert.callCount(fn, times[, message])
• t.assert.nthCalledWith(fn, n, ...args)
• t.assert.lastCalledWith(fn, ...args)

This is syntactic sugar. Everything here can already be written with fn.mock.callCount(), fn.mock.calls and assert.deepStrictEqual(). It is also possible today in userland with assert.register(). The goal is to make the most common mock checks shorter. Like the other t.assert methods, these count toward t.plan().

nthCalledWith (1-based, like Jest/Vitest) and lastCalledWith check a single call, so their failures show a regular deepStrictEqual diff.

Examples from nodejs/doc-kit

logger.test.mjs

// Before
strictEqual(transport.mock.callCount(), 1);

const call = transport.mock.calls[0];
deepStrictEqual(call.arguments, [
  {
    level: LogLevel.debug,
    message: 'Hello, World!',
    metadata,
    module: undefined,
    timestamp: 0,
  },
]);

// After
t.assert.callCount(transport, 1);
t.assert.nthCalledWith(transport, 1, {
  level: LogLevel.debug,
  message: 'Hello, World!',
  metadata,
  module: undefined,
  timestamp: 0,
});

transports/github.test.mjs

// Before
const callsArgs = process.stdout.write.mock.calls.map(
  call => call.arguments[0]
);

strictEqual(process.stdout.write.mock.callCount(), 1);
strictEqual(
  callsArgs[0].trim(),
  '::debug::[00:00:00.000] \x1B[34mDEBUG\x1B[39m: Test message'
);

// After
t.assert.callCount(process.stdout.write, 1);
t.assert.nthCalledWith(
  process.stdout.write,
  1,
  '::debug::[00:00:00.000] \x1B[34mDEBUG\x1B[39m: Test message\n'
);

[nodejs-github-bot]

Review requested:

• @nodejs/test_runner

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.40%. Comparing base (bbd566d) to head (be90007).
⚠️ Report is 4 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #66476      +/-   ##
==========================================
- Coverage   92.74%   90.40%   -2.35%     
==========================================
  Files         422      791     +369     
  Lines      193170   276097   +82927     
  Branches    29783    52986   +23203     
==========================================
+ Hits       179160   249605   +70445     
- Misses      13682    16905    +3223     
- Partials      328     9587    +9259     

Files with missing lines	Coverage Δ
lib/internal/test_runner/assert.js	100.00% <100.00%> (ø)
lib/internal/test_runner/mock/mock.js	97.32% <100.00%> (+0.44%)	⬆️

... and 499 files with indirect coverage changes

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