gleam-lang/gleam

Gleam LSP won't show autocomplete on function return type

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#5332 opened on Jan 28, 2026

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 (5 comments) (0 reactions) (0 assignees)Rust (21,417 stars) (960 forks)batch import
help wanted

Description

How to reproduce:

  1. Type your function (fn square() -> I)
  2. After typing 'I' the LSP doesn't give 'Int' or other suggestion.

Gleam v1.14, tree-sitter-gleam v1.10

Contributor guide

Tech stack
rust
Domain
developer experience
Issue type
bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
half day
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
fresh
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
Familiarity with LSP protocolUnderstanding of tree sitter grammar
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
55
Research direction
Investigate the LSP completion provider in language server/src/completion.rs to understand why no suggestions appear after typing ' >'. Check the tree sitter gleam grammar to ensure the parser correctly captures the return type token. Look for existing tests for autocomplete on function signatures and review the issue comments for any hints.