Function parse_describe_query

crates/gitql-parser/src/parser.rs:179–221

(
    env: &mut Environment,
    tokens: &[Token],
    position: &mut usize,
)

}

fn parse_describe_query(
    env: &mut Environment,
    tokens: &[Token],
    position: &mut usize,
) -> Result<Query, Box<Diagnostic>> {
    // Consume `DESCRIBE` keyword
    *position += 1;

    if *position >= tokens.len() || !matches!(tokens[*position].kind, TokenKind::Symbol(_)) {
        return Err(
            Diagnostic::error("Expect table name after DESCRIBE Statement")
                .with_location(calculate_safe_location(tokens, *position))
                .as_boxed(),
        );
    }

    // Make sure table name is valid
    let table_name = tokens[*position].to_string();
    if !env
        .schema
        .tables_fields_names
        .contains_key(table_name.as_str())
    {
        let mut diagnostic =
            Diagnostic::error(&format!("Cannot find table with name `{table_name}`"))
                .add_note("You can use the `SHOW TABLES` query to get list of current tables")
                .add_note("Check the documentations to see available tables")
                .with_location(calculate_safe_location(tokens, *position));

        let canditates: Vec<&&str> = env.schema.tables_fields_names.keys().collect();
        if let Some(closest_valid_name) = find_closeest_string(&table_name, &canditates) {
            let message = &format!("a table with a similar name exists: `{closest_valid_name}`");
            diagnostic = diagnostic.add_help(message);
        }

        return Err(diagnostic.as_boxed());
    }

    // Consume Table Name
    *position += 1;

    Ok(Query::DescribeTable(DescribeQuery { table_name }))
}

fn parse_show_query(tokens: &[Token], position: &mut usize) -> Result<Query, Box<Diagnostic>> {
    // Consume SHOW keyword