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use fonts::parse_ui::*;
/// Test that zero-copy UIFontFace works correctly
#[test]
fn test_zero_copy_functionality() {
let parser = UIFontParser::new();
// Create some dummy font data
let font_data = vec![0x00, 0x01, 0x02, 0x03, 0x04, 0x05];
// Create UIFontFace with borrowed data (zero-copy)
let font_faces = vec![UIFontFace {
face_id: "demo-font.ttf".to_string(),
data: &font_data, // ← This borrows the data, no copying!
user_font_style_italic: None,
}];
// The parser should work with the borrowed data
// (This will fail with invalid font data, but that's expected)
let result = parser.analyze_family(Some("Demo".to_string()), font_faces);
// We expect this to fail because the data is not a valid font,
// but the important thing is that it compiles and runs without copying the data
assert!(result.is_err());
// The original font_data is still available and unchanged
assert_eq!(font_data.len(), 6);
assert_eq!(font_data[0], 0x00);
}
/// Test that verifies the memory efficiency of zero-copy approach
#[test]
fn test_memory_efficiency() {
// Create a large font data array
let large_font_data = vec![0u8; 1024 * 1024]; // 1MB of data
// Create multiple UIFontFace instances that all borrow the same data
let font_faces = vec![
UIFontFace {
face_id: "font1.ttf".to_string(),
data: &large_font_data, // ← Borrows, doesn't copy
user_font_style_italic: None,
},
UIFontFace {
face_id: "font2.ttf".to_string(),
data: &large_font_data, // ← Borrows the same data
user_font_style_italic: None,
},
UIFontFace {
face_id: "font3.ttf".to_string(),
data: &large_font_data, // ← Borrows the same data
user_font_style_italic: None,
},
];
// All three UIFontFace instances share the same underlying data
// Memory usage: 1MB (original) + 3 * 8 bytes (pointers) = ~1MB total
// vs. the old approach: 1MB * 4 = 4MB total
let parser = UIFontParser::new();
let result = parser.analyze_family(Some("Demo".to_string()), font_faces);
// This will fail due to invalid font data, but that's not the point
// The point is that we can create multiple UIFontFace instances without copying data
assert!(result.is_err());
// The original data is still available
assert_eq!(large_font_data.len(), 1024 * 1024);
}