Method handle_selection_range

src/selection_range.rs:25–67

Compute selection ranges for the given positions in the file.

(
        &self,
        content: &str,
        positions: &[Position],
    )

impl Backend {
    /// Compute selection ranges for the given positions in the file.
    pub fn handle_selection_range(
        &self,
        content: &str,
        positions: &[Position],
    ) -> Option<Vec<SelectionRange>> {
        let arena = Bump::new();
        let file_id = mago_database::file::FileId::new("input.php");
        let program = mago_syntax::parser::parse_file_content(&arena, file_id, content);

        let mut results = Vec::with_capacity(positions.len());

        for pos in positions {
            let offset = position_to_offset(content, *pos);

            // Collect all spans that contain the cursor, from the AST walk.
            let mut spans: Vec<(u32, u32)> = Vec::new();

            // Add the whole-file span as the outermost range.
            let file_span = (0u32, content.len() as u32);
            spans.push(file_span);

            for stmt in program.statements.iter() {
                collect_spans_from_statement(stmt, offset, &mut spans);
            }

            // Deduplicate identical spans and sort outermost-first (largest
            // span first).  When two spans have the same length, the one
            // starting earlier comes first.
            spans.sort_unstable();
            spans.dedup();
            spans.sort_by(|a, b| {
                let len_a = a.1.saturating_sub(a.0);
                let len_b = b.1.saturating_sub(b.0);
                len_b.cmp(&len_a).then(a.0.cmp(&b.0))
            });

            // Build the linked list from outermost to innermost.
            let selection_range = build_selection_range(content, &spans);
            results.push(selection_range);
        }

        Some(results)
    }
}

// ─── Linked-list builder ────────────────────────────────────────────────────