Module intel 

Language services — completion, signature help, hover.

In-process, no LSP. Each service is one small trait defined here in the core and satisfied by the app — not a god-trait with no-op defaults; a service ruled out of scope is simply not built. The plain data the traits exchange lives here too, so a provider never reaches an editor internal. Completion is synchronous by contract (the classifier is a regex ladder over a few dozen lines — microseconds), so the widget calls the provider in update() and opens the popup from the returned Vec the same frame; no async reply, no revision guard.

The controller state machines (completion / snippet session) that consume these providers are core view-state and land in the submodules below.

Modules

completion

The completion controller state machine — core view-state, driven by the widget and headlessly tested against a stub provider. It owns the popup list, local prefix filtering, Escape-stickiness, and the provider-call budget (at most one complete() per input event); it never touches the document. Accepting returns the chosen item for the caller to apply as one sealed transaction.

hover

Hover — the Hover trait the app satisfies plus the plain data it returns. Like the other language services it is synchronous by contract: a hover query is an in-memory lookup keyed by the word under the pointer, so the widget calls it on the mouse-idle tick and renders the reply the same frame. Because the answer is produced synchronously there is no reply envelope and nothing in flight, so a reply can never arrive stale.

providers

The completion provider contract: the Completions trait the app satisfies, plus the plain-data types it exchanges. Every type here is inert data — no editor internal is reachable from a provider.

signature

Signature help — the SignatureHelp trait the app satisfies plus the plain data it returns. No controller: signature help is stateless per query (the app re-runs it on ( / , / edits and shows or hides the one-line box from the reply), so unlike completion there is no sticky state machine.

snippet

The snippet parser: the LSP placeholder subset spec.rs emits, parsed into a body with defaults expanded plus an ordered list of tab stops. Pure text — no document, no transaction; the session state machine that drives the decoration store consumes this. Items stay inert data until accept time, so parsing happens then, never earlier.