Matchers API

All exported from astro-dist-compress. Every matcher has the shape (ctx: ImageContext) => boolean — you can freely mix them with plain functions.

inDir(...globs: string[])

Matches images anywhere under the given directory glob(s). A bare directory path (no *) automatically matches everything beneath it.

inDir("assets/hero");        // matches assets/hero/anything.png
inDir("assets/**/thumbs");   // glob patterns work too
inDir("a", "b");             // matches under "a" OR under "b"

pathMatches(...globs: string[])

Matches the image's full relative path against the given glob(s).

pathMatches("**/icons/*.png");

hasFormat(...formats: ImageFormat[])

Matches images whose decoded source format (not just file extension) is one of the given values.

hasFormat("png");
hasFormat("jpeg", "jpg");

hasAlpha(expected = true)

Matches images with (or, passing false, without) an alpha channel.

hasAlpha();       // has transparency
hasAlpha(false);  // opaque

largerThan({ width?, height? })

Matches images at or above the given pixel dimensions. Either field can be omitted.

largerThan({ width: 1200 });
largerThan({ width: 1200, height: 800 });

biggerThan(bytes: number)

Matches images at or above the given file size, in bytes.

biggerThan(20_000); // 20 KB or larger

and(...matchers) / or(...matchers) / not(matcher)

Combine matchers with boolean logic.

and(hasFormat("png"), hasAlpha(true), biggerThan(20_000));
or(hasFormat("jpeg"), hasFormat("jpg"));
not(inDir("assets/icons"));