watchexec/crates/filterer/tagged/src/lib.rs

88 lines
4.1 KiB
Rust

//! A filterer implementation that exposes the full capabilities of Watchexec.
//!
//! Filters match against [event tags][Tag]; can be exact matches, glob matches, regex matches, or
//! set matches; can reverse the match (equal/not equal, etc); and can be negated.
//!
//! [Filters][Filter] can be generated from your application and inserted directly, or they can be
//! parsed from a textual format:
//!
//! ```text
//! [!]{Matcher}{Op}{Value}
//! ```
//!
//! For example:
//!
//! ```text
//! path==/foo/bar
//! path*=**/bar
//! path~=bar$
//! !kind=file
//! ```
//!
//! There is a set of [operators][Op]:
//! - `==` and `!=`: exact match and exact not match (case insensitive)
//! - `~=` and `~!`: regex match and regex not match
//! - `*=` and `*!`: glob match and glob not match
//! - `:=` and `:!`: set match and set not match
//!
//! Sets are a list of values separated by `,`.
//!
//! In addition to the two-symbol operators, there is the `=` "auto" operator, which maps to the
//! most convenient operator for the given _matcher_. The current mapping is:
//!
//! | Matcher | Operator |
//! |-------------------------------------------------|---------------|
//! | [Tag](Matcher::Tag) | `:=` (in set) |
//! | [Path](Matcher::Path) | `*=` (glob) |
//! | [FileType](Matcher::FileType) | `:=` (in set) |
//! | [FileEventKind](Matcher::FileEventKind) | `*=` (glob) |
//! | [Source](Matcher::Source) | `:=` (in set) |
//! | [Process](Matcher::Process) | `:=` (in set) |
//! | [Signal](Matcher::Signal) | `:=` (in set) |
//! | [ProcessCompletion](Matcher::ProcessCompletion) | `*=` (glob) |
//! | [Priority](Matcher::Priority) | `:=` (in set) |
//!
//! [Matchers][Matcher] correspond to Tags, but are not one-to-one: the `path` matcher operates on
//! the `path` part of the `Path` tag, and the `type` matcher operates on the `file_type`, for
//! example.
//!
//! | Matcher | Syntax | Tag |
//! |------------------------------------|----------|----------------------------------------------|
//! | [Tag](Matcher::Tag) | `tag` | _the presence of a Tag on the event_ |
//! | [Path](Matcher::Path) | `path` | [Path](Tag::Path) (`path` field) |
//! | [FileType](Matcher::FileType) | `type` | [Path](Tag::Path) (`file_type` field, when Some) |
//! | [FileEventKind](Matcher::FileEventKind) | `kind` or `fek` | [FileEventKind](Tag::FileEventKind) |
//! | [Source](Matcher::Source) | `source` or `src` | [Source](Tag::Source) |
//! | [Process](Matcher::Process) | `process` or `pid` | [Process](Tag::Process) |
//! | [Signal](Matcher::Signal) | `signal` | [Signal](Tag::Signal) |
//! | [ProcessCompletion](Matcher::ProcessCompletion) | `complete` or `exit` | [ProcessCompletion](Tag::ProcessCompletion) |
//! | [Priority](Matcher::Priority) | `priority` | special: event [Priority] |
//!
//! Filters are checked in order, grouped per tag and per matcher. Filter groups may be checked in
//! any order, but the filters in the groups are checked in add order. Path glob filters are always
//! checked first, for internal reasons.
//!
//! The `negate` boolean field behaves specially: it is not operator negation, but rather the same
//! kind of behaviour that is applied to `!`-prefixed globs in gitignore files: if a negated filter
//! matches the event, the result of the event checking for that matcher is reverted to `true`, even
//! if a previous filter set it to `false`. Unmatched negated filters are ignored.
//!
//! Glob syntax is as supported by the [ignore] crate for Paths, and by [globset] otherwise. (As of
//! writing, the ignore crate uses globset internally). Regex syntax is the default syntax of the
//! [regex] crate.
// to make filters
pub use regex::Regex;
pub use error::*;
pub use files::*;
pub use filter::*;
pub use filterer::*;
mod error;
mod files;
mod filter;
mod filterer;
mod parse;
mod swaplock;