AnsiTestReporterThe built-in terminal reporter: aligned [Suite] tags, one line per test with a green '.' or red '!' per assertion, per-suite and whole-run summaries, and failure detail with file:line:column locations โ all in ANSI color on the stream given at construction (qn test passes [IO]Stdout).
Print the assertion's mark: a green '.' for a pass, a red '!' for a failure.
Print the whole-run summary: total assertion time, wall time, and pass / failure / skip counts.
Print the suite's summary line: pass/failure counts, assertion time and wall time.
Finish the test's line with its timings; a failing test then lists each failed assertion's evidence and file:line:column.
Set the output stream: anything answering write: / writeln:.
Current suite's name padded to the widest suite name, so every [Tag] aligns."
No mark at assertion start โ the '.'/'!' prints once the outcome is known, in endAssertion:.
Measure the widest suite name, so every [Suite] tag aligns.
Announce the suite: 'Running N tests', or the SKIPPED line with the suite's reason.
Start the test's output line: suite tag and test name; the assertion marks follow on the same line.