perl-testing

Use Test2::V0 with is(), ok(), and subtest blocks, ending each file with done_testing. It supports deep comparison builders like hash, array, and bag for partial structure matching with better failure diagnostics than Test::More.

Test2::V0 is the modern replacement offering richer assertions, better diagnostics, and extensible plugins, while remaining backward-compatible with Test::More tests. New projects should prefer Test2::V0; Test::More still ships with core Perl.

Run prove -lr t/ to execute all tests recursively with lib/ in @INC. Add -v for verbose output, -j8 for parallel execution, and --state=failed to rerun only previously failing tests.

Use Test::MockModule to override methods on a package; the mock restores automatically when the object goes out of scope. For lightweight test doubles, Test::MockObject creates injectable objects with call verification via called_ok().

Run cover -test to execute the suite under coverage, then cover -report html for a browsable report. In CI, parse the text report total and fail the build when coverage drops below your threshold, such as 80 percent.

prove fails with 'Can't locate module in @INC' when the -l flag is missing, because lib/ is not added to the include path. Always run prove -l or configure it in a .proverc file.