Compatibility

linegauge (its default export), linegauge/wrap, linegauge/strip and linegauge/slice are graded, not described as compatible. Each is run against its incumbent's own test suite, by compat-oracle, in CI.

The counts are compat-oracle's baselines, the pass count each drop-in is held to. The family's compatibility page is generated from the oracle's last run and is the authority for the current figures, beside every other drop-in in the family.

How a suite is gradedCopy Anchor Link

1. The incumbent's repository is cloned at the release tag of the graded version and its test file copied into packages/compat-oracle/vendor/. No incumbent ships its tests to npm, so a tarball could not be used. Each copy's PROVENANCE file names the tag, the commit and the command that reproduces it.
2. The only edit is the import that reaches the library: it is rewritten to a shim generated per run. Assertions, fixtures and helpers are upstream's, byte for byte.
3. A control run points the shim at the real incumbent first. That proves the harness before it grades anything of ours, and the control's total is what every rate is measured against.
4. The target run points the same shim at linegauge's path.

Beyond the suitesCopy Anchor Link

Each path is also graded differentially in linegauge's own tests, against the real incumbent installed beside it: wrap.test.ts compares wrap with wrap-ansi on thirty named inputs under six option sets and on two hundred generated ones, slice.test.ts compares every [start, end) of its corpus with slice-ansi, and strip.test.ts compares sixteen sequence shapes with strip-ansi. truncate, which has no drop-in path, is compared case by case with cli-truncate.

Known differencesCopy Anchor Link

• The ellipsis of truncate is never styled. cli-truncate paints it in the text's colour at two of its three positions and not the third; truncate puts it after the closing sequence at all three. There is no linegauge/cli-truncate, so no import moves onto this by accident (Slicing and truncating).
• A width plugin changes every answer. With nothing registered — the default — every path gives Unicode's answer, which is what the suites grade. Registering a widths plugin is how you ask for a different one (Width plugins).

Types and CommonJSCopy Anchor Link

Each path's default export is the incumbent's default, and its options type is exported under the incumbent's name — Options from linegauge and from linegauge/wrap — so a TypeScript program migrates by its import alone. require('linegauge') returns the namespace, whose default is width, and an overrides entry can move a transitive string-width onto it:

{ "overrides": { "string-width": "npm:linegauge@^0.5" } }