Module ignores 

Configurable exclusion for a synced root (docs/design/fs-watch.md “Ignoring”).

Three sources, composed into one matcher and evaluated per path:

• .git — a pure name filter, no git data read.
• ignore files — the enclosing worktree’s exclude stack: every .gitignore / .ignore from the worktree top down to the deepest directory on the path, plus $GIT_DIR/info/exclude and the user’s core.excludesFile.
• client patterns — gitignore syntax, anchored at the sync root, highest precedence so !keep-this re-includes what the rest hide.

Precedence is git’s: the deepest ignore file wins over shallower ones, a match on an ancestor directory excludes everything below it (which is why a negation cannot resurrect a file under an excluded directory), and client patterns sit above the whole stack.

Filtering is not a view over a full index — an excluded path is never stated, indexed, hashed, or counted against the entry budget, and its hints are dropped before the settle tick. That is the whole point: a sync of a checkout should cost the checkout, not node_modules.

Structs

IgnoreSpec

What a sync excludes. Part of the shared root’s identity (crate::RootKey): two syncs indexing different trees cannot share a reconciler, exactly as for recursive — so this derives Hash/Eq over the normalized pattern list rather than over a compiled matcher.

Ignores

Compiled exclusion for one root. Per-directory matchers are built on first use and memoized, so the initial scan reads each .gitignore once and incremental reconciliation reads none.

Constants

DOT_IGNORE_NAME

The non-git per-directory ignore file — ripgrep’s convention, honored by the FS_INDEX / FS_GREP walkers and selectable here on its own.

GITIGNORE_NAME

The git per-directory ignore file. Lower in the same directory than DOT_IGNORE_NAME is: within one directory .gitignore wins, matching the walkers.

MAX_PATTERNS

Cap on client patterns, so a hostile FS_SYNC cannot compile an unbounded glob set. Refused at request validation, not silently cut.