Module completion 

Core completion infrastructure for deps-lsp.

This module provides generic completion functionality that works across all package ecosystems (Cargo, npm, PyPI, etc.). It handles:

• Context detection - determining what type of completion is appropriate
• Prefix extraction - getting the text typed so far
• CompletionItem builders - creating LSP completion responses

Architecture

The completion system uses trait objects (dyn Dependency, dyn ParseResult, dyn Version, dyn Metadata) to work generically across ecosystems.

Examples

use deps_core::completion::{detect_completion_context, CompletionContext};
use tower_lsp_server::ls_types::Position;

// In your ecosystem's generate_completions implementation:
async fn generate_completions(
    parse_result: &dyn deps_core::ParseResult,
    position: Position,
    content: &str,
) -> Vec<tower_lsp_server::ls_types::CompletionItem> {
    let context = detect_completion_context(parse_result, position, content);

    match context {
        CompletionContext::PackageName { prefix, range } => {
            // Search registry and build completions, replacing `range`
            vec![]
        }
        CompletionContext::Version { package_name, prefix } => {
            // Fetch versions and build completions
            vec![]
        }
        _ => vec![],
    }
}

Structs

Completions

Result of Ecosystem::generate_completions.

VersionDisplayItem

Display metadata for a single version in LSP responses.

Enums

CompletionContext

Context for completion request based on cursor position.

Constants

COMPLETION_SEARCH_TIMEOUT

Wall-clock budget deps-lsp’s completion handler gives an ecosystem’s generate_completions before treating it as a timeout.

Functions

build_feature_completion

Builds a completion item for a feature flag.

build_package_completion

Builds a completion item for a package name.

build_version_completion

Builds a completion item for a version string.

byte_to_utf16_offset

Converts a byte offset within s to a UTF-16 code unit offset (LSP Position.character).

complete_package_names_generic

Generic package name completion using any Registry implementation.

complete_versions_at_position

Version completion resolved by cursor position, not by package name (issue #593).

complete_versions_generic

Generic version completion logic used by all ecosystems.

complete_versions_generic_from

Like complete_versions_generic, but resolves through crate::Registry::get_versions_from.

detect_completion_context

Detects the completion context based on cursor position.

extract_feature_prefix

Extracts the partial feature name typed at the cursor position.

extract_prefix

Extracts the prefix text from content at a position within a range.

is_valid_completion_prefix_len

Checks whether prefix has an acceptable length (2 to 200 characters, inclusive) for triggering a package-name completion search.

prepare_version_display_items

Filters and formats versions for LSP display.

utf16_to_byte_offset

Converts UTF-16 offset to byte offset in a string.