error-parser

Direction: shared types only (not called directly) · Capability: none (pure data / dispatch) · Worlds: error-parser-plugin (imports)

CM.6: plugin-contributed compilation-output parsers.

A plugin teaches lattice to recognise diagnostics from a build tool the editor has never heard of. The native set covers cargo/rustc, gnu-style, and test panics; everything else in the world — a bespoke linter, an in-house build system, a language whose compiler predates all of them — is what this is for.

Line at a time, because the format is

feed takes ONE line and returns the entries that line completed. A multi-line format (cargo's error: header followed by an --> file:l:c arrow two lines later) keeps its own pending state inside the guest and emits when the location arrives; a single-line format emits or returns nothing. It mirrors the native CompilationParser trait exactly, because a plugin parser and a native one are the same job and should not have different shapes.

reset drops that pending state at the start of a run, so a build interrupted mid-diagnostic cannot leak a half-parsed entry into the next one.

Where it runs

Off the UI and actor threads, in the compilation reader (see compilation-mode.md §5). Not the keystroke path — but it IS the critical path of a fast producer, so a guest that blocks here backs up a build's output. The host budgets it per call like every other seam.

What the host does with a bad entry

Validates and drops, never traps. A returned line/col is guest data and the host treats it as untrusted: a nonsense path or an entry with an empty path is logged at debug and skipped, exactly as a native parser's malformed-but-claimed match is. One bad line must not fail a build.

Functions (0)

(none — a shared type interface)

Types (2)

enum `severity`

enum severity {
    error,
    warning,
    info,
    note,
}

Severity of a parsed diagnostic. Mirrors the host's ErrorSeverity.

record `entry`

record entry {
    path: string,
    line: u32,
    col: u32,
    severity: severity,
    message: string,
}

One diagnostic the parser recognised.

Fields

path: string — Path as the tool printed it. Relative paths resolve against the compilation's working directory, host-side — the guest does not need to know where the build ran.
line: u32 — 0-based line, like the host's ErrorEntry. A tool printing 1-based line numbers (nearly all of them) subtracts one; doing that in the guest keeps one convention on this side of the boundary instead of two.
col: u32 — 0-based column.
severity: severity
message: string