Function iterate_queries

datafusion/core/tests/sql/unparser.rs:63–94

Reads all `.sql` files from a directory and converts them to test queries. Skips files that: - Are not regular files - Don't have a `.sql` extension - Contain multiple SQL statements (indicated by `;\n`) Multi-statement files are skipped because the unparser doesn't support DML statements like `CREATE VIEW` that appear in multi-statement Clickbench queries.

(dir: ReadDir)

/// Multi-statement files are skipped because the unparser doesn't support
/// DML statements like `CREATE VIEW` that appear in multi-statement Clickbench queries.
fn iterate_queries(dir: ReadDir) -> Vec<TestQuery> {
    let mut queries = vec![];
    for entry in dir.flatten() {
        let Ok(file_type) = entry.file_type() else {
            continue;
        };
        if !file_type.is_file() {
            continue;
        }
        let path = entry.path();
        let Some(ext) = path.extension() else {
            continue;
        };
        if ext != "sql" {
            continue;
        }
        let name = path.file_stem().unwrap().to_string_lossy().to_string();
        if let Ok(mut contents) = std::fs::read_to_string(entry.path()) {
            // If the query contains ;\n it has DML statements like CREATE VIEW which the unparser doesn't support; skip it
            contents = contents.trim().to_string();
            if contents.contains(";\n") {
                println!("Skipping query with multiple statements: {name}");
                continue;
            }
            queries.push(TestQuery {
                sql: contents,
                name,
            });
        }
    }
    queries
}

/// A SQL query loaded from a benchmark file for roundtrip testing.
///