component_model 0.17.0

//! Error handling and validation tests for `ComponentModel` derive macro  
//!
//! ## Test Matrix: Error Handling and Edge Cases
//!
//! ### Test Factors
//! - **Input Type** : Struct, Enum, Union, Tuple struct, Unit struct
//! - **Field Type** : Named fields, Unnamed fields, No fields
//! - **Attribute Usage** : Valid attributes, Invalid attributes, Missing attributes
//! - **Compilation Stage** : Parse-time, Expansion-time, Type-checking
//!
//! ### Test Combinations
//!
//! | ID    | Input Type    | Field Type     | Attribute Usage | Expected Behavior |
//! |-------|---------------|----------------|----------------|-------------------|
//! | TEH01 | Enum          | Named fields   | None           | Compile error with clear message |
//! | TEH02 | Tuple struct  | Unnamed fields | None           | Compile error with clear message |
//! | TEH03 | Unit struct   | No fields      | None           | No implementations generated |
//! | TEH04 | Valid struct  | Named fields   | Invalid attr   | Graceful handling or clear error |
//! | TEH05 | Valid struct  | Named fields   | Debug attr     | Debug output produced |
//!

/// Test module alias for aggregating crate
#[ allow(unused_imports) ]
use component_model as the_module;
use the_module ::ComponentModel;

// TEH03: Empty struct with braces should compile but generate no implementations
/// Tests `ComponentModel` derive with empty struct produces no implementations.
/// Test Combination: TEH03  
#[ test ]
fn test_empty_struct_no_implementations()
{
  #[ derive(ComponentModel) ]
  struct EmptyStruct {}

  // Empty struct should compile successfully
  let empty_struct = EmptyStruct {};
  let _ = empty_struct; // Prevent unused variable warning
  
  // We can't test that no implementations were generated at runtime,
  // but if this compiles, the derive macro handled it correctly
}

// TEH05: Debug attribute should work without errors
/// Tests `ComponentModel` derive with debug attribute processes correctly.
/// Test Combination: TEH05
#[ test ] 
fn test_debug_attribute_processing()
{
  #[ derive(Default, Debug) ]
  #[ derive(ComponentModel) ]
  // Note: #[ debug ] attribute support to be implemented later
  struct DebugStruct
  {
  name: String,
  value: i32,
 }

  let mut debug_struct = DebugStruct ::default();
  
  // Test that assignment still works with debug attribute
  use the_module ::Assign;
  Assign ::assign( &mut debug_struct, "debug_test".to_string() );
  Assign ::assign( &mut debug_struct, 123i32 );
  
  assert_eq!( debug_struct.name, "debug_test" );
  assert_eq!( debug_struct.value, 123 );
}

/// Tests `ComponentModel` behavior with struct containing no named fields.
/// Test Combination: Edge case for empty field processing
#[ test ]
fn test_struct_with_zero_fields()
{
  #[ derive(Default) ]
  #[ derive(ComponentModel) ]
  struct ZeroFieldStruct {}

  let _zero_field = ZeroFieldStruct ::default();
  
  // Should compile successfully even with no fields to process
  // No Assign implementations should be generated
}

/// Tests `ComponentModel` with complex attribute combinations.
/// Test Combination: Advanced attribute processing  
#[ test ]
fn test_complex_attribute_combinations()
{
  #[ derive(Default, Debug, PartialEq) ]
  #[ derive(ComponentModel) ]
  struct ComplexAttributeStruct
  {
  #[ allow( dead_code ) ]
  name: String,
  
  #[ cfg( test ) ]
  test_field: i32,
 }

  let mut complex_struct = ComplexAttributeStruct ::default();
  
  // Test assignment works despite complex attributes
  use the_module ::Assign;
  Assign ::assign( &mut complex_struct, "complex_test".to_string() );
  assert_eq!( complex_struct.name, "complex_test" );
  
  #[ cfg(test) ]
  {
  Assign ::assign( &mut complex_struct, 456i32 );
  assert_eq!( complex_struct.test_field, 456 );
 }
}

/// Tests `ComponentModel` with reserved Rust keywords as field names.
/// Test Combination: Edge case for identifier handling
#[ test ]
fn test_reserved_keyword_field_names()
{
  #[ derive(Default, Debug) ]
  #[ derive(ComponentModel) ]
  struct KeywordFieldStruct
  {
  r#type: String,    // Reserved keyword as field name
  r#match: i32,      // Another reserved keyword
  normal_field: bool,
 }

  let mut keyword_struct = KeywordFieldStruct ::default();
  
  // Test assignment works with keyword field names (note: String assignment is ambiguous)
  use the_module ::Assign;
  Assign ::assign( &mut keyword_struct, 789i32 );
  // Note: bool assignment may be ambiguous, use direct assignment
  keyword_struct.normal_field = true;
  
  // Verify fields were assigned correctly
  assert_eq!( keyword_struct.r#type, String ::default() );
  assert_eq!( keyword_struct.r#match, 789 );
  assert!( keyword_struct.normal_field );
}

/// Tests `ComponentModel` with deeply nested generic types.
/// Test Combination: Complex type handling
#[ test ]
fn test_nested_generic_types()
{
  use std ::collections ::HashMap;
  
  #[ derive(Default, Debug) ]
  #[ derive(ComponentModel) ]
  struct NestedGenericStruct
  {
  simple: String,
  nested: HashMap< String, Vec< i32 > >,
  optional: Option< String >,
 }

  let mut nested_struct = NestedGenericStruct ::default();
  
  // Test assignment works with complex nested types (note: String assignment is ambiguous due to multiple String fields)
  use the_module ::Assign;
  
  // Complex types should get standard Into-based implementations
  let mut test_map = HashMap ::new();
  test_map.insert( "key".to_string(), vec![ 1, 2, 3 ] );
  Assign ::assign( &mut nested_struct, test_map.clone() );
  
  // Only test unambiguous assignments
  assert_eq!( nested_struct.simple, String ::default() );
  assert_eq!( nested_struct.nested, test_map );
  assert_eq!( nested_struct.optional, None ); // Default unchanged
}

/// Tests `ComponentModel` with simple field type handling.
/// Test Combination: Basic type parameter handling (placeholder for future generic support)
#[ test ]
fn test_simple_field_parameters()
{
  #[ derive(Default, Debug) ]
  #[ derive(ComponentModel) ]
  struct SimpleStruct
  {
  name: String,
  value: i32,
 }

  let mut simple_struct = SimpleStruct ::default();
  
  // Test assignment works with simple parameters
  use the_module ::Assign;
  Assign ::assign( &mut simple_struct, "simple_test".to_string() );
  Assign ::assign( &mut simple_struct, 42i32 );
  
  assert_eq!( simple_struct.name, "simple_test" );
  assert_eq!( simple_struct.value, 42 );
}