crates/pgls_completions/README.md
The pgls_completions identifies and ranks autocompletion items that can be displayed in your code editor.
Its main export is the complete function. The function takes a PostgreSQL statement, a cursor position, and a datastructure representing the underlying databases schema. It returns a list of completion items.
Postgres's statement-parsing-engine, libpg_query, which is used in other parts of this LSP, is only capable of parsing complete and valid statements. Since autocompletion should work for incomplete statements, we rely heavily on tree-sitter – an incremental parsing library.
In the pgls_test_utils crate, there's a binary that parses an SQL file and prints out the matching tree-sitter tree.
This makes writing tree-sitter queries for this crate easy.
To print a tree, run cargo run --bin tree_print -- -f <your_sql_file>.