When using --stdin-filepath, ignorePatterns from .oxfmtrc.json is not applied. The file content is still formatted and output to stdout, even though the filepath matches an ignore pattern.

This is the stdin counterpart of #17729, which was fixed for CLI positional arguments in #17732. The --stdin-filepath code path appears to skip the ignore check.

Repro

// .oxfmtrc.json
{
  "ignorePatterns": ["ignored/**"]
}

// ignored/should-be-ignored.ts
const   x   =   1;
const y={a:1,b:2,c:3,d:4,e:5};
function   foo(   a:string,b:   number,   c:boolean   ){return    a+b+c}

cat ignored/should-be-ignored.ts | oxfmt --stdin-filepath ignored/should-be-ignored.ts -c .oxfmtrc.json

Expected

The original content should be output unchanged (file is ignored).

Prettier has the expected behavior — if the filepath matches .prettierignore, prettier --stdin-filepath outputs the content unchanged.

Actual

The file is fully formatted:

const x = 1;
const y = { a: 1, b: 2, c: 3, d: 4, e: 5 };
function foo(a: string, b: number, c: boolean) {
  return a + b + c;
}

Why this matters

Jujutsu (jj) has a jj fix feature that operates by piping file contents through stdin and reading formatted output from stdout. It relies on --stdin-filepath to give the formatter the file path context. Without ignorePatterns being respected in this code path, jj fix will format files that should be ignored.

Environment

• oxfmt: 0.41.0
• macOS (arm64)