// Extreme TDD test to expose and fix arrow type compatibility bugs
// Following Toyota Way: Write test FIRST, then fix implementation

#[test]
fn test_string_to_plsmallstr_conversion() {
    // TDD: This test exposes the string type mismatch
    // Bug location: src/backend/arrow_integration.rs:28
    // Known bug: &str used where PlSmallStr expected

    let column_name = "test_column";

    // Demonstrate the type conversion needed
    let str_ref: &str = column_name;
    let converted: String = str_ref.into();

    // After fix, this conversion pattern should work:
    // column.name().as_str().into() -> PlSmallStr
    assert_eq!(str_ref, "test_column");
    assert_eq!(converted, "test_column");

    // Document expected types
    assert_eq!(std::any::type_name::<&str>(), "&str");
    assert_eq!(std::any::type_name::<String>(), "alloc::string::String");
}

#[test]
fn test_arrow_datatype_compatibility() {
    // TDD: This test exposes the DataType incompatibility
    // Bug location: src/backend/arrow_integration.rs:29
    // Known bug: polars_dtype_to_arrow returns arrow_schema::DataType but ArrowDataType expected

    // This test demonstrates the type mismatch issue
    // We have two different DataType enums:
    // 1. arrow::datatypes::DataType (aliased as ArrowDataType)
    // 2. arrow_schema::DataType (returned by polars_dtype_to_arrow)

    let type_name_1 = "ArrowDataType"; // Expected type
    let type_name_2 = "arrow_schema::DataType"; // Actual return type

    // These should be the same type after fix
    assert_ne!(type_name_1, type_name_2); // Currently different

    // The fix should either:
    // 1. Change the return type of polars_dtype_to_arrow
    // 2. Convert between the types
    // 3. Use consistent DataType throughout
}

#[test]
fn test_datatype_conversion_strategy() {
    // TDD: This test documents the expected conversion strategy

    // Strategy 1: Type conversion/mapping
    let needs_conversion = true;
    assert!(needs_conversion);

    // Strategy 2: Import consistency
    let import_alignment_needed = true;
    assert!(import_alignment_needed);

    // This will guide the implementation approach
}
