1use crate::{
2 Bounds, DevicePixels, Font, FontFallbacks, FontFeatures, FontId, FontMetrics, FontRun,
3 FontStyle, FontWeight, GlyphId, LineLayout, Pixels, PlatformTextSystem, Point,
4 RenderGlyphParams, Result, SUBPIXEL_VARIANTS_X, ShapedGlyph, ShapedRun, SharedString, Size,
5 point, px, size, swap_rgba_pa_to_bgra,
6};
7use anyhow::anyhow;
8use cocoa::appkit::CGFloat;
9use collections::HashMap;
10use core_foundation::{
11 array::{CFArray, CFArrayRef},
12 attributed_string::CFMutableAttributedString,
13 base::{CFRange, TCFType},
14 number::CFNumber,
15 string::CFString,
16};
17use core_graphics::{
18 base::{CGGlyph, kCGImageAlphaPremultipliedLast},
19 color_space::CGColorSpace,
20 context::{CGContext, CGTextDrawingMode},
21 display::CGPoint,
22};
23use core_text::{
24 font::CTFont,
25 font_collection::CTFontCollectionRef,
26 font_descriptor::{
27 CTFontDescriptor, kCTFontSlantTrait, kCTFontSymbolicTrait, kCTFontWeightTrait,
28 kCTFontWidthTrait,
29 },
30 line::CTLine,
31 string_attributes::kCTFontAttributeName,
32};
33use font_kit::{
34 font::Font as FontKitFont,
35 handle::Handle,
36 hinting::HintingOptions,
37 metrics::Metrics,
38 properties::{Style as FontkitStyle, Weight as FontkitWeight},
39 source::SystemSource,
40 sources::mem::MemSource,
41};
42use parking_lot::{RwLock, RwLockUpgradableReadGuard};
43use pathfinder_geometry::{
44 rect::{RectF, RectI},
45 transform2d::Transform2F,
46 vector::{Vector2F, Vector2I},
47};
48use smallvec::SmallVec;
49use std::{borrow::Cow, char, convert::TryFrom, sync::Arc};
50
51use super::open_type::apply_features_and_fallbacks;
52
53#[allow(non_upper_case_globals)]
54const kCGImageAlphaOnly: u32 = 7;
55
56pub(crate) struct MacTextSystem(RwLock<MacTextSystemState>);
57
58#[derive(Clone, PartialEq, Eq, Hash)]
59struct FontKey {
60 font_family: SharedString,
61 font_features: FontFeatures,
62 font_fallbacks: Option<FontFallbacks>,
63}
64
65struct MacTextSystemState {
66 memory_source: MemSource,
67 system_source: SystemSource,
68 fonts: Vec<FontKitFont>,
69 font_selections: HashMap<Font, FontId>,
70 font_ids_by_postscript_name: HashMap<String, FontId>,
71 font_ids_by_font_key: HashMap<FontKey, SmallVec<[FontId; 4]>>,
72 postscript_names_by_font_id: HashMap<FontId, String>,
73}
74
75impl MacTextSystem {
76 pub(crate) fn new() -> Self {
77 Self(RwLock::new(MacTextSystemState {
78 memory_source: MemSource::empty(),
79 system_source: SystemSource::new(),
80 fonts: Vec::new(),
81 font_selections: HashMap::default(),
82 font_ids_by_postscript_name: HashMap::default(),
83 font_ids_by_font_key: HashMap::default(),
84 postscript_names_by_font_id: HashMap::default(),
85 }))
86 }
87}
88
89impl Default for MacTextSystem {
90 fn default() -> Self {
91 Self::new()
92 }
93}
94
95impl PlatformTextSystem for MacTextSystem {
96 fn add_fonts(&self, fonts: Vec<Cow<'static, [u8]>>) -> Result<()> {
97 self.0.write().add_fonts(fonts)
98 }
99
100 fn all_font_names(&self) -> Vec<String> {
101 let mut names = Vec::new();
102 let collection = core_text::font_collection::create_for_all_families();
103 // NOTE: We intentionally avoid using `collection.get_descriptors()` here because
104 // it has a memory leak bug in core-text v21.0.0. The upstream code uses
105 // `wrap_under_get_rule` but `CTFontCollectionCreateMatchingFontDescriptors`
106 // follows the Create Rule (caller owns the result), so it should use
107 // `wrap_under_create_rule`. We call the function directly with correct memory management.
108 unsafe extern "C" {
109 fn CTFontCollectionCreateMatchingFontDescriptors(
110 collection: CTFontCollectionRef,
111 ) -> CFArrayRef;
112 }
113 let descriptors: Option<CFArray<CTFontDescriptor>> = unsafe {
114 let array_ref =
115 CTFontCollectionCreateMatchingFontDescriptors(collection.as_concrete_TypeRef());
116 if array_ref.is_null() {
117 None
118 } else {
119 Some(CFArray::wrap_under_create_rule(array_ref))
120 }
121 };
122 let Some(descriptors) = descriptors else {
123 return names;
124 };
125 for descriptor in descriptors.into_iter() {
126 names.extend(lenient_font_attributes::family_name(&descriptor));
127 }
128 if let Ok(fonts_in_memory) = self.0.read().memory_source.all_families() {
129 names.extend(fonts_in_memory);
130 }
131 names
132 }
133
134 fn font_id(&self, font: &Font) -> Result<FontId> {
135 let lock = self.0.upgradable_read();
136 if let Some(font_id) = lock.font_selections.get(font) {
137 Ok(*font_id)
138 } else {
139 let mut lock = RwLockUpgradableReadGuard::upgrade(lock);
140 let font_key = FontKey {
141 font_family: font.family.clone(),
142 font_features: font.features.clone(),
143 font_fallbacks: font.fallbacks.clone(),
144 };
145 let candidates = if let Some(font_ids) = lock.font_ids_by_font_key.get(&font_key) {
146 font_ids.as_slice()
147 } else {
148 let font_ids =
149 lock.load_family(&font.family, &font.features, font.fallbacks.as_ref())?;
150 lock.font_ids_by_font_key.insert(font_key.clone(), font_ids);
151 lock.font_ids_by_font_key[&font_key].as_ref()
152 };
153
154 let candidate_properties = candidates
155 .iter()
156 .map(|font_id| lock.fonts[font_id.0].properties())
157 .collect::<SmallVec<[_; 4]>>();
158
159 let ix = font_kit::matching::find_best_match(
160 &candidate_properties,
161 &font_kit::properties::Properties {
162 style: font.style.into(),
163 weight: font.weight.into(),
164 stretch: Default::default(),
165 },
166 )?;
167
168 let font_id = candidates[ix];
169 lock.font_selections.insert(font.clone(), font_id);
170 Ok(font_id)
171 }
172 }
173
174 fn font_metrics(&self, font_id: FontId) -> FontMetrics {
175 self.0.read().fonts[font_id.0].metrics().into()
176 }
177
178 fn typographic_bounds(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Bounds<f32>> {
179 Ok(self.0.read().fonts[font_id.0]
180 .typographic_bounds(glyph_id.0)?
181 .into())
182 }
183
184 fn advance(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Size<f32>> {
185 self.0.read().advance(font_id, glyph_id)
186 }
187
188 fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option<GlyphId> {
189 self.0.read().glyph_for_char(font_id, ch)
190 }
191
192 fn glyph_raster_bounds(&self, params: &RenderGlyphParams) -> Result<Bounds<DevicePixels>> {
193 self.0.read().raster_bounds(params)
194 }
195
196 fn rasterize_glyph(
197 &self,
198 glyph_id: &RenderGlyphParams,
199 raster_bounds: Bounds<DevicePixels>,
200 ) -> Result<(Size<DevicePixels>, Vec<u8>)> {
201 self.0.read().rasterize_glyph(glyph_id, raster_bounds)
202 }
203
204 fn layout_line(&self, text: &str, font_size: Pixels, font_runs: &[FontRun]) -> LineLayout {
205 self.0.write().layout_line(text, font_size, font_runs)
206 }
207}
208
209impl MacTextSystemState {
210 fn add_fonts(&mut self, fonts: Vec<Cow<'static, [u8]>>) -> Result<()> {
211 let fonts = fonts
212 .into_iter()
213 .map(|bytes| match bytes {
214 Cow::Borrowed(embedded_font) => {
215 let data_provider = unsafe {
216 core_graphics::data_provider::CGDataProvider::from_slice(embedded_font)
217 };
218 let font = core_graphics::font::CGFont::from_data_provider(data_provider)
219 .map_err(|()| anyhow!("Could not load an embedded font."))?;
220 let font = font_kit::loaders::core_text::Font::from_core_graphics_font(font);
221 Ok(Handle::from_native(&font))
222 }
223 Cow::Owned(bytes) => Ok(Handle::from_memory(Arc::new(bytes), 0)),
224 })
225 .collect::<Result<Vec<_>>>()?;
226 self.memory_source.add_fonts(fonts.into_iter())?;
227 Ok(())
228 }
229
230 fn load_family(
231 &mut self,
232 name: &str,
233 features: &FontFeatures,
234 fallbacks: Option<&FontFallbacks>,
235 ) -> Result<SmallVec<[FontId; 4]>> {
236 let name = crate::text_system::font_name_with_fallbacks(name, ".AppleSystemUIFont");
237
238 let mut font_ids = SmallVec::new();
239 let family = self
240 .memory_source
241 .select_family_by_name(name)
242 .or_else(|_| self.system_source.select_family_by_name(name))?;
243 for font in family.fonts() {
244 let mut font = font.load()?;
245
246 apply_features_and_fallbacks(&mut font, features, fallbacks)?;
247 // This block contains a precautionary fix to guard against loading fonts
248 // that might cause panics due to `.unwrap()`s up the chain.
249 {
250 // We use the 'm' character for text measurements in various spots
251 // (e.g., the editor). However, at time of writing some of those usages
252 // will panic if the font has no 'm' glyph.
253 //
254 // Therefore, we check up front that the font has the necessary glyph.
255 let has_m_glyph = font.glyph_for_char('m').is_some();
256
257 // HACK: The 'Segoe Fluent Icons' font does not have an 'm' glyph,
258 // but we need to be able to load it for rendering Windows icons in
259 // the Storybook (on macOS).
260 let is_segoe_fluent_icons = font.full_name() == "Segoe Fluent Icons";
261
262 if !has_m_glyph && !is_segoe_fluent_icons {
263 // I spent far too long trying to track down why a font missing the 'm'
264 // character wasn't loading. This log statement will hopefully save
265 // someone else from suffering the same fate.
266 log::warn!(
267 "font '{}' has no 'm' character and was not loaded",
268 font.full_name()
269 );
270 continue;
271 }
272 }
273
274 // We've seen a number of panics in production caused by calling font.properties()
275 // which unwraps a downcast to CFNumber. This is an attempt to avoid the panic,
276 // and to try and identify the incalcitrant font.
277 let traits = font.native_font().all_traits();
278 if unsafe {
279 !(traits
280 .get(kCTFontSymbolicTrait)
281 .downcast::<CFNumber>()
282 .is_some()
283 && traits
284 .get(kCTFontWidthTrait)
285 .downcast::<CFNumber>()
286 .is_some()
287 && traits
288 .get(kCTFontWeightTrait)
289 .downcast::<CFNumber>()
290 .is_some()
291 && traits
292 .get(kCTFontSlantTrait)
293 .downcast::<CFNumber>()
294 .is_some())
295 } {
296 log::error!(
297 "Failed to read traits for font {:?}",
298 font.postscript_name().unwrap()
299 );
300 continue;
301 }
302
303 let font_id = FontId(self.fonts.len());
304 font_ids.push(font_id);
305 let postscript_name = font.postscript_name().unwrap();
306 self.font_ids_by_postscript_name
307 .insert(postscript_name.clone(), font_id);
308 self.postscript_names_by_font_id
309 .insert(font_id, postscript_name);
310 self.fonts.push(font);
311 }
312 Ok(font_ids)
313 }
314
315 fn advance(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Size<f32>> {
316 Ok(self.fonts[font_id.0].advance(glyph_id.0)?.into())
317 }
318
319 fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option<GlyphId> {
320 self.fonts[font_id.0].glyph_for_char(ch).map(GlyphId)
321 }
322
323 fn id_for_native_font(&mut self, requested_font: CTFont) -> FontId {
324 let postscript_name = requested_font.postscript_name();
325 if let Some(font_id) = self.font_ids_by_postscript_name.get(&postscript_name) {
326 *font_id
327 } else {
328 let font_id = FontId(self.fonts.len());
329 self.font_ids_by_postscript_name
330 .insert(postscript_name.clone(), font_id);
331 self.postscript_names_by_font_id
332 .insert(font_id, postscript_name);
333 self.fonts
334 .push(font_kit::font::Font::from_core_graphics_font(
335 requested_font.copy_to_CGFont(),
336 ));
337 font_id
338 }
339 }
340
341 fn is_emoji(&self, font_id: FontId) -> bool {
342 self.postscript_names_by_font_id
343 .get(&font_id)
344 .is_some_and(|postscript_name| {
345 postscript_name == "AppleColorEmoji" || postscript_name == ".AppleColorEmojiUI"
346 })
347 }
348
349 fn raster_bounds(&self, params: &RenderGlyphParams) -> Result<Bounds<DevicePixels>> {
350 let font = &self.fonts[params.font_id.0];
351 let scale = Transform2F::from_scale(params.scale_factor);
352 Ok(font
353 .raster_bounds(
354 params.glyph_id.0,
355 params.font_size.into(),
356 scale,
357 HintingOptions::None,
358 font_kit::canvas::RasterizationOptions::GrayscaleAa,
359 )?
360 .into())
361 }
362
363 fn rasterize_glyph(
364 &self,
365 params: &RenderGlyphParams,
366 glyph_bounds: Bounds<DevicePixels>,
367 ) -> Result<(Size<DevicePixels>, Vec<u8>)> {
368 if glyph_bounds.size.width.0 == 0 || glyph_bounds.size.height.0 == 0 {
369 anyhow::bail!("glyph bounds are empty");
370 } else {
371 // Add an extra pixel when the subpixel variant isn't zero to make room for anti-aliasing.
372 let mut bitmap_size = glyph_bounds.size;
373 if params.subpixel_variant.x > 0 {
374 bitmap_size.width += DevicePixels(1);
375 }
376 if params.subpixel_variant.y > 0 {
377 bitmap_size.height += DevicePixels(1);
378 }
379 let bitmap_size = bitmap_size;
380
381 let mut bytes;
382 let cx;
383 if params.is_emoji {
384 bytes = vec![0; bitmap_size.width.0 as usize * 4 * bitmap_size.height.0 as usize];
385 cx = CGContext::create_bitmap_context(
386 Some(bytes.as_mut_ptr() as *mut _),
387 bitmap_size.width.0 as usize,
388 bitmap_size.height.0 as usize,
389 8,
390 bitmap_size.width.0 as usize * 4,
391 &CGColorSpace::create_device_rgb(),
392 kCGImageAlphaPremultipliedLast,
393 );
394 } else {
395 bytes = vec![0; bitmap_size.width.0 as usize * bitmap_size.height.0 as usize];
396 cx = CGContext::create_bitmap_context(
397 Some(bytes.as_mut_ptr() as *mut _),
398 bitmap_size.width.0 as usize,
399 bitmap_size.height.0 as usize,
400 8,
401 bitmap_size.width.0 as usize,
402 &CGColorSpace::create_device_gray(),
403 kCGImageAlphaOnly,
404 );
405 }
406
407 // Move the origin to bottom left and account for scaling, this
408 // makes drawing text consistent with the font-kit's raster_bounds.
409 cx.translate(
410 -glyph_bounds.origin.x.0 as CGFloat,
411 (glyph_bounds.origin.y.0 + glyph_bounds.size.height.0) as CGFloat,
412 );
413 cx.scale(
414 params.scale_factor as CGFloat,
415 params.scale_factor as CGFloat,
416 );
417
418 let subpixel_shift = params
419 .subpixel_variant
420 .map(|v| v as f32 / SUBPIXEL_VARIANTS_X as f32);
421 cx.set_text_drawing_mode(CGTextDrawingMode::CGTextFill);
422 cx.set_gray_fill_color(0.0, 1.0);
423 cx.set_allows_antialiasing(true);
424 cx.set_should_antialias(true);
425 cx.set_allows_font_subpixel_positioning(true);
426 cx.set_should_subpixel_position_fonts(true);
427 cx.set_allows_font_subpixel_quantization(false);
428 cx.set_should_subpixel_quantize_fonts(false);
429 self.fonts[params.font_id.0]
430 .native_font()
431 .clone_with_font_size(f32::from(params.font_size) as CGFloat)
432 .draw_glyphs(
433 &[params.glyph_id.0 as CGGlyph],
434 &[CGPoint::new(
435 (subpixel_shift.x / params.scale_factor) as CGFloat,
436 (subpixel_shift.y / params.scale_factor) as CGFloat,
437 )],
438 cx,
439 );
440
441 if params.is_emoji {
442 // Convert from RGBA with premultiplied alpha to BGRA with straight alpha.
443 for pixel in bytes.chunks_exact_mut(4) {
444 swap_rgba_pa_to_bgra(pixel);
445 }
446 }
447
448 Ok((bitmap_size, bytes))
449 }
450 }
451
452 fn layout_line(&mut self, text: &str, font_size: Pixels, font_runs: &[FontRun]) -> LineLayout {
453 // Construct the attributed string, converting UTF8 ranges to UTF16 ranges.
454 let mut string = CFMutableAttributedString::new();
455 let mut max_ascent = 0.0f32;
456 let mut max_descent = 0.0f32;
457
458 {
459 let mut text = text;
460 let mut break_ligature = true;
461 for run in font_runs {
462 let text_run;
463 (text_run, text) = text.split_at(run.len);
464
465 let utf16_start = string.char_len(); // insert at end of string
466 // note: replace_str may silently ignore codepoints it dislikes (e.g., BOM at start of string)
467 string.replace_str(&CFString::new(text_run), CFRange::init(utf16_start, 0));
468 let utf16_end = string.char_len();
469
470 let length = utf16_end - utf16_start;
471 let cf_range = CFRange::init(utf16_start, length);
472 let font = &self.fonts[run.font_id.0];
473
474 let font_metrics = font.metrics();
475 let font_scale = font_size.0 / font_metrics.units_per_em as f32;
476 max_ascent = max_ascent.max(font_metrics.ascent * font_scale);
477 max_descent = max_descent.max(-font_metrics.descent * font_scale);
478
479 let font_size = if break_ligature {
480 px(font_size.0.next_up())
481 } else {
482 font_size
483 };
484 unsafe {
485 string.set_attribute(
486 cf_range,
487 kCTFontAttributeName,
488 &font.native_font().clone_with_font_size(font_size.into()),
489 );
490 }
491 break_ligature = !break_ligature;
492 }
493 }
494 // Retrieve the glyphs from the shaped line, converting UTF16 offsets to UTF8 offsets.
495 let line = CTLine::new_with_attributed_string(string.as_concrete_TypeRef());
496 let glyph_runs = line.glyph_runs();
497 let mut runs = <Vec<ShapedRun>>::with_capacity(glyph_runs.len() as usize);
498 let mut ix_converter = StringIndexConverter::new(text);
499 for run in glyph_runs.into_iter() {
500 let attributes = run.attributes().unwrap();
501 let font = unsafe {
502 attributes
503 .get(kCTFontAttributeName)
504 .downcast::<CTFont>()
505 .unwrap()
506 };
507 let font_id = self.id_for_native_font(font);
508
509 let mut glyphs = match runs.last_mut() {
510 Some(run) if run.font_id == font_id => &mut run.glyphs,
511 _ => {
512 runs.push(ShapedRun {
513 font_id,
514 glyphs: Vec::with_capacity(run.glyph_count().try_into().unwrap_or(0)),
515 });
516 &mut runs.last_mut().unwrap().glyphs
517 }
518 };
519 for ((&glyph_id, position), &glyph_utf16_ix) in run
520 .glyphs()
521 .iter()
522 .zip(run.positions().iter())
523 .zip(run.string_indices().iter())
524 {
525 let mut glyph_utf16_ix = usize::try_from(glyph_utf16_ix).unwrap();
526 if ix_converter.utf16_ix > glyph_utf16_ix {
527 // We cannot reuse current index converter, as it can only seek forward. Restart the search.
528 ix_converter = StringIndexConverter::new(text);
529 }
530 ix_converter.advance_to_utf16_ix(glyph_utf16_ix);
531 glyphs.push(ShapedGlyph {
532 id: GlyphId(glyph_id as u32),
533 position: point(position.x as f32, position.y as f32).map(px),
534 index: ix_converter.utf8_ix,
535 is_emoji: self.is_emoji(font_id),
536 });
537 }
538 }
539 let typographic_bounds = line.get_typographic_bounds();
540 LineLayout {
541 runs,
542 font_size,
543 width: typographic_bounds.width.into(),
544 ascent: max_ascent.into(),
545 descent: max_descent.into(),
546 len: text.len(),
547 }
548 }
549}
550
551#[derive(Debug, Clone)]
552struct StringIndexConverter<'a> {
553 text: &'a str,
554 /// Index in UTF-8 bytes
555 utf8_ix: usize,
556 /// Index in UTF-16 code units
557 utf16_ix: usize,
558}
559
560impl<'a> StringIndexConverter<'a> {
561 fn new(text: &'a str) -> Self {
562 Self {
563 text,
564 utf8_ix: 0,
565 utf16_ix: 0,
566 }
567 }
568
569 fn advance_to_utf16_ix(&mut self, utf16_target: usize) {
570 for (ix, c) in self.text[self.utf8_ix..].char_indices() {
571 if self.utf16_ix >= utf16_target {
572 self.utf8_ix += ix;
573 return;
574 }
575 self.utf16_ix += c.len_utf16();
576 }
577 self.utf8_ix = self.text.len();
578 }
579}
580
581impl From<Metrics> for FontMetrics {
582 fn from(metrics: Metrics) -> Self {
583 FontMetrics {
584 units_per_em: metrics.units_per_em,
585 ascent: metrics.ascent,
586 descent: metrics.descent,
587 line_gap: metrics.line_gap,
588 underline_position: metrics.underline_position,
589 underline_thickness: metrics.underline_thickness,
590 cap_height: metrics.cap_height,
591 x_height: metrics.x_height,
592 bounding_box: metrics.bounding_box.into(),
593 }
594 }
595}
596
597impl From<RectF> for Bounds<f32> {
598 fn from(rect: RectF) -> Self {
599 Bounds {
600 origin: point(rect.origin_x(), rect.origin_y()),
601 size: size(rect.width(), rect.height()),
602 }
603 }
604}
605
606impl From<RectI> for Bounds<DevicePixels> {
607 fn from(rect: RectI) -> Self {
608 Bounds {
609 origin: point(DevicePixels(rect.origin_x()), DevicePixels(rect.origin_y())),
610 size: size(DevicePixels(rect.width()), DevicePixels(rect.height())),
611 }
612 }
613}
614
615impl From<Vector2I> for Size<DevicePixels> {
616 fn from(value: Vector2I) -> Self {
617 size(value.x().into(), value.y().into())
618 }
619}
620
621impl From<RectI> for Bounds<i32> {
622 fn from(rect: RectI) -> Self {
623 Bounds {
624 origin: point(rect.origin_x(), rect.origin_y()),
625 size: size(rect.width(), rect.height()),
626 }
627 }
628}
629
630impl From<Point<u32>> for Vector2I {
631 fn from(size: Point<u32>) -> Self {
632 Vector2I::new(size.x as i32, size.y as i32)
633 }
634}
635
636impl From<Vector2F> for Size<f32> {
637 fn from(vec: Vector2F) -> Self {
638 size(vec.x(), vec.y())
639 }
640}
641
642impl From<FontWeight> for FontkitWeight {
643 fn from(value: FontWeight) -> Self {
644 FontkitWeight(value.0)
645 }
646}
647
648impl From<FontStyle> for FontkitStyle {
649 fn from(style: FontStyle) -> Self {
650 match style {
651 FontStyle::Normal => FontkitStyle::Normal,
652 FontStyle::Italic => FontkitStyle::Italic,
653 FontStyle::Oblique => FontkitStyle::Oblique,
654 }
655 }
656}
657
658// Some fonts may have no attributes despite `core_text` requiring them (and panicking).
659// This is the same version as `core_text` has without `expect` calls.
660mod lenient_font_attributes {
661 use core_foundation::{
662 base::{CFRetain, CFType, TCFType},
663 string::{CFString, CFStringRef},
664 };
665 use core_text::font_descriptor::{
666 CTFontDescriptor, CTFontDescriptorCopyAttribute, kCTFontFamilyNameAttribute,
667 };
668
669 pub fn family_name(descriptor: &CTFontDescriptor) -> Option<String> {
670 unsafe { get_string_attribute(descriptor, kCTFontFamilyNameAttribute) }
671 }
672
673 fn get_string_attribute(
674 descriptor: &CTFontDescriptor,
675 attribute: CFStringRef,
676 ) -> Option<String> {
677 unsafe {
678 let value = CTFontDescriptorCopyAttribute(descriptor.as_concrete_TypeRef(), attribute);
679 if value.is_null() {
680 return None;
681 }
682
683 let value = CFType::wrap_under_create_rule(value);
684 assert!(value.instance_of::<CFString>());
685 let s = wrap_under_get_rule(value.as_CFTypeRef() as CFStringRef);
686 Some(s.to_string())
687 }
688 }
689
690 unsafe fn wrap_under_get_rule(reference: CFStringRef) -> CFString {
691 unsafe {
692 assert!(!reference.is_null(), "Attempted to create a NULL object.");
693 let reference = CFRetain(reference as *const ::std::os::raw::c_void) as CFStringRef;
694 TCFType::wrap_under_create_rule(reference)
695 }
696 }
697}
698
699#[cfg(test)]
700mod tests {
701 use crate::{FontRun, GlyphId, MacTextSystem, PlatformTextSystem, font, px};
702
703 #[test]
704 fn test_layout_line_bom_char() {
705 let fonts = MacTextSystem::new();
706 let font_id = fonts.font_id(&font("Helvetica")).unwrap();
707 let line = "\u{feff}";
708 let mut style = FontRun {
709 font_id,
710 len: line.len(),
711 };
712
713 let layout = fonts.layout_line(line, px(16.), &[style]);
714 assert_eq!(layout.len, line.len());
715 assert!(layout.runs.is_empty());
716
717 let line = "a\u{feff}b";
718 style.len = line.len();
719 let layout = fonts.layout_line(line, px(16.), &[style]);
720 assert_eq!(layout.len, line.len());
721 assert_eq!(layout.runs.len(), 1);
722 assert_eq!(layout.runs[0].glyphs.len(), 2);
723 assert_eq!(layout.runs[0].glyphs[0].id, GlyphId(68u32)); // a
724 // There's no glyph for \u{feff}
725 assert_eq!(layout.runs[0].glyphs[1].id, GlyphId(69u32)); // b
726
727 let line = "\u{feff}ab";
728 let font_runs = &[
729 FontRun {
730 len: "\u{feff}".len(),
731 font_id,
732 },
733 FontRun {
734 len: "ab".len(),
735 font_id,
736 },
737 ];
738 let layout = fonts.layout_line(line, px(16.), font_runs);
739 assert_eq!(layout.len, line.len());
740 assert_eq!(layout.runs.len(), 1);
741 assert_eq!(layout.runs[0].glyphs.len(), 2);
742 // There's no glyph for \u{feff}
743 assert_eq!(layout.runs[0].glyphs[0].id, GlyphId(68u32)); // a
744 assert_eq!(layout.runs[0].glyphs[1].id, GlyphId(69u32)); // b
745 }
746
747 #[test]
748 fn test_layout_line_zwnj_insertion() {
749 let fonts = MacTextSystem::new();
750 let font_id = fonts.font_id(&font("Helvetica")).unwrap();
751
752 let text = "hello world";
753 let font_runs = &[
754 FontRun { font_id, len: 5 }, // "hello"
755 FontRun { font_id, len: 6 }, // " world"
756 ];
757
758 let layout = fonts.layout_line(text, px(16.), font_runs);
759 assert_eq!(layout.len, text.len());
760
761 for run in &layout.runs {
762 for glyph in &run.glyphs {
763 assert!(
764 glyph.index < text.len(),
765 "Glyph index {} is out of bounds for text length {}",
766 glyph.index,
767 text.len()
768 );
769 }
770 }
771
772 // Test with different font runs - should not insert ZWNJ
773 let font_id2 = fonts.font_id(&font("Times")).unwrap_or(font_id);
774 let font_runs_different = &[
775 FontRun { font_id, len: 5 }, // "hello"
776 // " world"
777 FontRun {
778 font_id: font_id2,
779 len: 6,
780 },
781 ];
782
783 let layout2 = fonts.layout_line(text, px(16.), font_runs_different);
784 assert_eq!(layout2.len, text.len());
785
786 for run in &layout2.runs {
787 for glyph in &run.glyphs {
788 assert!(
789 glyph.index < text.len(),
790 "Glyph index {} is out of bounds for text length {}",
791 glyph.index,
792 text.len()
793 );
794 }
795 }
796 }
797
798 #[test]
799 fn test_layout_line_zwnj_edge_cases() {
800 let fonts = MacTextSystem::new();
801 let font_id = fonts.font_id(&font("Helvetica")).unwrap();
802
803 let text = "hello";
804 let font_runs = &[FontRun { font_id, len: 5 }];
805 let layout = fonts.layout_line(text, px(16.), font_runs);
806 assert_eq!(layout.len, text.len());
807
808 let text = "abc";
809 let font_runs = &[
810 FontRun { font_id, len: 1 }, // "a"
811 FontRun { font_id, len: 1 }, // "b"
812 FontRun { font_id, len: 1 }, // "c"
813 ];
814 let layout = fonts.layout_line(text, px(16.), font_runs);
815 assert_eq!(layout.len, text.len());
816
817 for run in &layout.runs {
818 for glyph in &run.glyphs {
819 assert!(
820 glyph.index < text.len(),
821 "Glyph index {} is out of bounds for text length {}",
822 glyph.index,
823 text.len()
824 );
825 }
826 }
827
828 // Test with empty text
829 let text = "";
830 let font_runs = &[];
831 let layout = fonts.layout_line(text, px(16.), font_runs);
832 assert_eq!(layout.len, 0);
833 assert!(layout.runs.is_empty());
834 }
835}