1use crate::{
2 point, px, size, Bounds, DevicePixels, Font, FontFeatures, FontId, FontMetrics, FontRun,
3 FontStyle, FontWeight, GlyphId, LineLayout, Pixels, PlatformTextSystem, Point,
4 RenderGlyphParams, Result, ShapedGlyph, ShapedRun, SharedString, Size, SUBPIXEL_VARIANTS,
5};
6use anyhow::anyhow;
7use cocoa::appkit::{CGFloat, CGPoint};
8use collections::{BTreeSet, HashMap};
9use core_foundation::{
10 array::CFIndex,
11 attributed_string::{CFAttributedStringRef, CFMutableAttributedString},
12 base::{CFRange, TCFType},
13 number::CFNumber,
14 string::CFString,
15};
16use core_graphics::{
17 base::{kCGImageAlphaPremultipliedLast, CGGlyph},
18 color_space::CGColorSpace,
19 context::CGContext,
20};
21use core_text::{
22 font::CTFont,
23 font_descriptor::{
24 kCTFontSlantTrait, kCTFontSymbolicTrait, kCTFontWeightTrait, kCTFontWidthTrait,
25 },
26 line::CTLine,
27 string_attributes::kCTFontAttributeName,
28};
29use font_kit::{
30 font::Font as FontKitFont,
31 handle::Handle,
32 hinting::HintingOptions,
33 metrics::Metrics,
34 properties::{Style as FontkitStyle, Weight as FontkitWeight},
35 source::SystemSource,
36 sources::mem::MemSource,
37};
38use parking_lot::{RwLock, RwLockUpgradableReadGuard};
39use pathfinder_geometry::{
40 rect::{RectF, RectI},
41 transform2d::Transform2F,
42 vector::{Vector2F, Vector2I},
43};
44use smallvec::SmallVec;
45use std::{borrow::Cow, char, cmp, convert::TryFrom, ffi::c_void, sync::Arc};
46
47use super::open_type;
48
49#[allow(non_upper_case_globals)]
50const kCGImageAlphaOnly: u32 = 7;
51
52pub(crate) struct MacTextSystem(RwLock<MacTextSystemState>);
53
54struct MacTextSystemState {
55 memory_source: MemSource,
56 system_source: SystemSource,
57 fonts: Vec<FontKitFont>,
58 font_selections: HashMap<Font, FontId>,
59 font_ids_by_postscript_name: HashMap<String, FontId>,
60 font_ids_by_family_name: HashMap<SharedString, SmallVec<[FontId; 4]>>,
61 postscript_names_by_font_id: HashMap<FontId, String>,
62}
63
64impl MacTextSystem {
65 pub(crate) fn new() -> Self {
66 Self(RwLock::new(MacTextSystemState {
67 memory_source: MemSource::empty(),
68 system_source: SystemSource::new(),
69 fonts: Vec::new(),
70 font_selections: HashMap::default(),
71 font_ids_by_postscript_name: HashMap::default(),
72 font_ids_by_family_name: HashMap::default(),
73 postscript_names_by_font_id: HashMap::default(),
74 }))
75 }
76}
77
78impl Default for MacTextSystem {
79 fn default() -> Self {
80 Self::new()
81 }
82}
83
84impl PlatformTextSystem for MacTextSystem {
85 fn add_fonts(&self, fonts: Vec<Cow<'static, [u8]>>) -> Result<()> {
86 self.0.write().add_fonts(fonts)
87 }
88
89 fn all_font_names(&self) -> Vec<String> {
90 let collection = core_text::font_collection::create_for_all_families();
91 let Some(descriptors) = collection.get_descriptors() else {
92 return Vec::new();
93 };
94 let mut names = BTreeSet::new();
95 for descriptor in descriptors.into_iter() {
96 names.extend(lenient_font_attributes::family_name(&descriptor));
97 }
98 if let Ok(fonts_in_memory) = self.0.read().memory_source.all_families() {
99 names.extend(fonts_in_memory);
100 }
101 names.into_iter().collect()
102 }
103
104 fn all_font_families(&self) -> Vec<String> {
105 self.0
106 .read()
107 .system_source
108 .all_families()
109 .expect("core text should never return an error")
110 }
111
112 fn font_id(&self, font: &Font) -> Result<FontId> {
113 let lock = self.0.upgradable_read();
114 if let Some(font_id) = lock.font_selections.get(font) {
115 Ok(*font_id)
116 } else {
117 let mut lock = RwLockUpgradableReadGuard::upgrade(lock);
118 let candidates = if let Some(font_ids) = lock.font_ids_by_family_name.get(&font.family)
119 {
120 font_ids.as_slice()
121 } else {
122 let font_ids = lock.load_family(&font.family, font.features)?;
123 lock.font_ids_by_family_name
124 .insert(font.family.clone(), font_ids);
125 lock.font_ids_by_family_name[&font.family].as_ref()
126 };
127
128 let candidate_properties = candidates
129 .iter()
130 .map(|font_id| lock.fonts[font_id.0].properties())
131 .collect::<SmallVec<[_; 4]>>();
132
133 let ix = font_kit::matching::find_best_match(
134 &candidate_properties,
135 &font_kit::properties::Properties {
136 style: font.style.into(),
137 weight: font.weight.into(),
138 stretch: Default::default(),
139 },
140 )?;
141
142 let font_id = candidates[ix];
143 lock.font_selections.insert(font.clone(), font_id);
144 Ok(font_id)
145 }
146 }
147
148 fn font_metrics(&self, font_id: FontId) -> FontMetrics {
149 self.0.read().fonts[font_id.0].metrics().into()
150 }
151
152 fn typographic_bounds(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Bounds<f32>> {
153 Ok(self.0.read().fonts[font_id.0]
154 .typographic_bounds(glyph_id.0)?
155 .into())
156 }
157
158 fn advance(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Size<f32>> {
159 self.0.read().advance(font_id, glyph_id)
160 }
161
162 fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option<GlyphId> {
163 self.0.read().glyph_for_char(font_id, ch)
164 }
165
166 fn glyph_raster_bounds(&self, params: &RenderGlyphParams) -> Result<Bounds<DevicePixels>> {
167 self.0.read().raster_bounds(params)
168 }
169
170 fn rasterize_glyph(
171 &self,
172 glyph_id: &RenderGlyphParams,
173 raster_bounds: Bounds<DevicePixels>,
174 ) -> Result<(Size<DevicePixels>, Vec<u8>)> {
175 self.0.read().rasterize_glyph(glyph_id, raster_bounds)
176 }
177
178 fn layout_line(&self, text: &str, font_size: Pixels, font_runs: &[FontRun]) -> LineLayout {
179 self.0.write().layout_line(text, font_size, font_runs)
180 }
181
182 fn wrap_line(
183 &self,
184 text: &str,
185 font_id: FontId,
186 font_size: Pixels,
187 width: Pixels,
188 ) -> Vec<usize> {
189 self.0.read().wrap_line(text, font_id, font_size, width)
190 }
191}
192
193impl MacTextSystemState {
194 fn add_fonts(&mut self, fonts: Vec<Cow<'static, [u8]>>) -> Result<()> {
195 let fonts = fonts
196 .into_iter()
197 .map(|bytes| match bytes {
198 Cow::Borrowed(embedded_font) => {
199 let data_provider = unsafe {
200 core_graphics::data_provider::CGDataProvider::from_slice(embedded_font)
201 };
202 let font = core_graphics::font::CGFont::from_data_provider(data_provider)
203 .map_err(|_| anyhow!("Could not load an embedded font."))?;
204 let font = font_kit::loaders::core_text::Font::from_core_graphics_font(font);
205 Ok(Handle::from_native(&font))
206 }
207 Cow::Owned(bytes) => Ok(Handle::from_memory(Arc::new(bytes), 0)),
208 })
209 .collect::<Result<Vec<_>>>()?;
210 self.memory_source.add_fonts(fonts.into_iter())?;
211 Ok(())
212 }
213
214 fn load_family(
215 &mut self,
216 name: &SharedString,
217 features: FontFeatures,
218 ) -> Result<SmallVec<[FontId; 4]>> {
219 let mut font_ids = SmallVec::new();
220 let family = self
221 .memory_source
222 .select_family_by_name(name.as_ref())
223 .or_else(|_| self.system_source.select_family_by_name(name.as_ref()))?;
224 for font in family.fonts() {
225 let mut font = font.load()?;
226
227 open_type::apply_features(&mut font, features);
228 let Some(_) = font.glyph_for_char('m') else {
229 continue;
230 };
231 // We've seen a number of panics in production caused by calling font.properties()
232 // which unwraps a downcast to CFNumber. This is an attempt to avoid the panic,
233 // and to try and identify the incalcitrant font.
234 let traits = font.native_font().all_traits();
235 if unsafe {
236 !(traits
237 .get(kCTFontSymbolicTrait)
238 .downcast::<CFNumber>()
239 .is_some()
240 && traits
241 .get(kCTFontWidthTrait)
242 .downcast::<CFNumber>()
243 .is_some()
244 && traits
245 .get(kCTFontWeightTrait)
246 .downcast::<CFNumber>()
247 .is_some()
248 && traits
249 .get(kCTFontSlantTrait)
250 .downcast::<CFNumber>()
251 .is_some())
252 } {
253 log::error!(
254 "Failed to read traits for font {:?}",
255 font.postscript_name().unwrap()
256 );
257 continue;
258 }
259
260 let font_id = FontId(self.fonts.len());
261 font_ids.push(font_id);
262 let postscript_name = font.postscript_name().unwrap();
263 self.font_ids_by_postscript_name
264 .insert(postscript_name.clone(), font_id);
265 self.postscript_names_by_font_id
266 .insert(font_id, postscript_name);
267 self.fonts.push(font);
268 }
269 Ok(font_ids)
270 }
271
272 fn advance(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Size<f32>> {
273 Ok(self.fonts[font_id.0].advance(glyph_id.0)?.into())
274 }
275
276 fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option<GlyphId> {
277 self.fonts[font_id.0].glyph_for_char(ch).map(GlyphId)
278 }
279
280 fn id_for_native_font(&mut self, requested_font: CTFont) -> FontId {
281 let postscript_name = requested_font.postscript_name();
282 if let Some(font_id) = self.font_ids_by_postscript_name.get(&postscript_name) {
283 *font_id
284 } else {
285 let font_id = FontId(self.fonts.len());
286 self.font_ids_by_postscript_name
287 .insert(postscript_name.clone(), font_id);
288 self.postscript_names_by_font_id
289 .insert(font_id, postscript_name);
290 self.fonts
291 .push(font_kit::font::Font::from_core_graphics_font(
292 requested_font.copy_to_CGFont(),
293 ));
294 font_id
295 }
296 }
297
298 fn is_emoji(&self, font_id: FontId) -> bool {
299 self.postscript_names_by_font_id
300 .get(&font_id)
301 .map_or(false, |postscript_name| {
302 postscript_name == "AppleColorEmoji"
303 })
304 }
305
306 fn raster_bounds(&self, params: &RenderGlyphParams) -> Result<Bounds<DevicePixels>> {
307 let font = &self.fonts[params.font_id.0];
308 let scale = Transform2F::from_scale(params.scale_factor);
309 Ok(font
310 .raster_bounds(
311 params.glyph_id.0,
312 params.font_size.into(),
313 scale,
314 HintingOptions::None,
315 font_kit::canvas::RasterizationOptions::GrayscaleAa,
316 )?
317 .into())
318 }
319
320 fn rasterize_glyph(
321 &self,
322 params: &RenderGlyphParams,
323 glyph_bounds: Bounds<DevicePixels>,
324 ) -> Result<(Size<DevicePixels>, Vec<u8>)> {
325 if glyph_bounds.size.width.0 == 0 || glyph_bounds.size.height.0 == 0 {
326 Err(anyhow!("glyph bounds are empty"))
327 } else {
328 // Add an extra pixel when the subpixel variant isn't zero to make room for anti-aliasing.
329 let mut bitmap_size = glyph_bounds.size;
330 if params.subpixel_variant.x > 0 {
331 bitmap_size.width += DevicePixels(1);
332 }
333 if params.subpixel_variant.y > 0 {
334 bitmap_size.height += DevicePixels(1);
335 }
336 let bitmap_size = bitmap_size;
337
338 let mut bytes;
339 let cx;
340 if params.is_emoji {
341 bytes = vec![0; bitmap_size.width.0 as usize * 4 * bitmap_size.height.0 as usize];
342 cx = CGContext::create_bitmap_context(
343 Some(bytes.as_mut_ptr() as *mut _),
344 bitmap_size.width.0 as usize,
345 bitmap_size.height.0 as usize,
346 8,
347 bitmap_size.width.0 as usize * 4,
348 &CGColorSpace::create_device_rgb(),
349 kCGImageAlphaPremultipliedLast,
350 );
351 } else {
352 bytes = vec![0; bitmap_size.width.0 as usize * bitmap_size.height.0 as usize];
353 cx = CGContext::create_bitmap_context(
354 Some(bytes.as_mut_ptr() as *mut _),
355 bitmap_size.width.0 as usize,
356 bitmap_size.height.0 as usize,
357 8,
358 bitmap_size.width.0 as usize,
359 &CGColorSpace::create_device_gray(),
360 kCGImageAlphaOnly,
361 );
362 }
363
364 // Move the origin to bottom left and account for scaling, this
365 // makes drawing text consistent with the font-kit's raster_bounds.
366 cx.translate(
367 -glyph_bounds.origin.x.0 as CGFloat,
368 (glyph_bounds.origin.y.0 + glyph_bounds.size.height.0) as CGFloat,
369 );
370 cx.scale(
371 params.scale_factor as CGFloat,
372 params.scale_factor as CGFloat,
373 );
374
375 let subpixel_shift = params
376 .subpixel_variant
377 .map(|v| v as f32 / SUBPIXEL_VARIANTS as f32);
378 cx.set_allows_font_subpixel_positioning(true);
379 cx.set_should_subpixel_position_fonts(true);
380 cx.set_allows_font_subpixel_quantization(false);
381 cx.set_should_subpixel_quantize_fonts(false);
382 self.fonts[params.font_id.0]
383 .native_font()
384 .clone_with_font_size(f32::from(params.font_size) as CGFloat)
385 .draw_glyphs(
386 &[params.glyph_id.0 as CGGlyph],
387 &[CGPoint::new(
388 (subpixel_shift.x / params.scale_factor) as CGFloat,
389 (subpixel_shift.y / params.scale_factor) as CGFloat,
390 )],
391 cx,
392 );
393
394 if params.is_emoji {
395 // Convert from RGBA with premultiplied alpha to BGRA with straight alpha.
396 for pixel in bytes.chunks_exact_mut(4) {
397 pixel.swap(0, 2);
398 let a = pixel[3] as f32 / 255.;
399 pixel[0] = (pixel[0] as f32 / a) as u8;
400 pixel[1] = (pixel[1] as f32 / a) as u8;
401 pixel[2] = (pixel[2] as f32 / a) as u8;
402 }
403 }
404
405 Ok((bitmap_size, bytes))
406 }
407 }
408
409 fn layout_line(&mut self, text: &str, font_size: Pixels, font_runs: &[FontRun]) -> LineLayout {
410 // Construct the attributed string, converting UTF8 ranges to UTF16 ranges.
411 let mut string = CFMutableAttributedString::new();
412 {
413 string.replace_str(&CFString::new(text), CFRange::init(0, 0));
414 let utf16_line_len = string.char_len() as usize;
415
416 let mut ix_converter = StringIndexConverter::new(text);
417 for run in font_runs {
418 let utf8_end = ix_converter.utf8_ix + run.len;
419 let utf16_start = ix_converter.utf16_ix;
420
421 if utf16_start >= utf16_line_len {
422 break;
423 }
424
425 ix_converter.advance_to_utf8_ix(utf8_end);
426 let utf16_end = cmp::min(ix_converter.utf16_ix, utf16_line_len);
427
428 let cf_range =
429 CFRange::init(utf16_start as isize, (utf16_end - utf16_start) as isize);
430
431 let font: &FontKitFont = &self.fonts[run.font_id.0];
432 unsafe {
433 string.set_attribute(
434 cf_range,
435 kCTFontAttributeName,
436 &font.native_font().clone_with_font_size(font_size.into()),
437 );
438 }
439
440 if utf16_end == utf16_line_len {
441 break;
442 }
443 }
444 }
445
446 // Retrieve the glyphs from the shaped line, converting UTF16 offsets to UTF8 offsets.
447 let line = CTLine::new_with_attributed_string(string.as_concrete_TypeRef());
448
449 let mut runs = Vec::new();
450 for run in line.glyph_runs().into_iter() {
451 let attributes = run.attributes().unwrap();
452 let font = unsafe {
453 attributes
454 .get(kCTFontAttributeName)
455 .downcast::<CTFont>()
456 .unwrap()
457 };
458 let font_id = self.id_for_native_font(font);
459
460 let mut ix_converter = StringIndexConverter::new(text);
461 let mut glyphs = SmallVec::new();
462 for ((glyph_id, position), glyph_utf16_ix) in run
463 .glyphs()
464 .iter()
465 .zip(run.positions().iter())
466 .zip(run.string_indices().iter())
467 {
468 let glyph_utf16_ix = usize::try_from(*glyph_utf16_ix).unwrap();
469 ix_converter.advance_to_utf16_ix(glyph_utf16_ix);
470 glyphs.push(ShapedGlyph {
471 id: GlyphId(*glyph_id as u32),
472 position: point(position.x as f32, position.y as f32).map(px),
473 index: ix_converter.utf8_ix,
474 is_emoji: self.is_emoji(font_id),
475 });
476 }
477
478 runs.push(ShapedRun { font_id, glyphs })
479 }
480
481 let typographic_bounds = line.get_typographic_bounds();
482 LineLayout {
483 runs,
484 font_size,
485 width: typographic_bounds.width.into(),
486 ascent: typographic_bounds.ascent.into(),
487 descent: typographic_bounds.descent.into(),
488 len: text.len(),
489 }
490 }
491
492 fn wrap_line(
493 &self,
494 text: &str,
495 font_id: FontId,
496 font_size: Pixels,
497 width: Pixels,
498 ) -> Vec<usize> {
499 let mut string = CFMutableAttributedString::new();
500 string.replace_str(&CFString::new(text), CFRange::init(0, 0));
501 let cf_range = CFRange::init(0, text.encode_utf16().count() as isize);
502 let font = &self.fonts[font_id.0];
503 unsafe {
504 string.set_attribute(
505 cf_range,
506 kCTFontAttributeName,
507 &font.native_font().clone_with_font_size(font_size.into()),
508 );
509
510 let typesetter = CTTypesetterCreateWithAttributedString(string.as_concrete_TypeRef());
511 let mut ix_converter = StringIndexConverter::new(text);
512 let mut break_indices = Vec::new();
513 while ix_converter.utf8_ix < text.len() {
514 let utf16_len = CTTypesetterSuggestLineBreak(
515 typesetter,
516 ix_converter.utf16_ix as isize,
517 width.into(),
518 ) as usize;
519 ix_converter.advance_to_utf16_ix(ix_converter.utf16_ix + utf16_len);
520 if ix_converter.utf8_ix >= text.len() {
521 break;
522 }
523 break_indices.push(ix_converter.utf8_ix);
524 }
525 break_indices
526 }
527 }
528}
529
530#[derive(Clone)]
531struct StringIndexConverter<'a> {
532 text: &'a str,
533 utf8_ix: usize,
534 utf16_ix: usize,
535}
536
537impl<'a> StringIndexConverter<'a> {
538 fn new(text: &'a str) -> Self {
539 Self {
540 text,
541 utf8_ix: 0,
542 utf16_ix: 0,
543 }
544 }
545
546 fn advance_to_utf8_ix(&mut self, utf8_target: usize) {
547 for (ix, c) in self.text[self.utf8_ix..].char_indices() {
548 if self.utf8_ix + ix >= utf8_target {
549 self.utf8_ix += ix;
550 return;
551 }
552 self.utf16_ix += c.len_utf16();
553 }
554 self.utf8_ix = self.text.len();
555 }
556
557 fn advance_to_utf16_ix(&mut self, utf16_target: usize) {
558 for (ix, c) in self.text[self.utf8_ix..].char_indices() {
559 if self.utf16_ix >= utf16_target {
560 self.utf8_ix += ix;
561 return;
562 }
563 self.utf16_ix += c.len_utf16();
564 }
565 self.utf8_ix = self.text.len();
566 }
567}
568
569#[repr(C)]
570pub(crate) struct __CFTypesetter(c_void);
571
572type CTTypesetterRef = *const __CFTypesetter;
573
574#[link(name = "CoreText", kind = "framework")]
575extern "C" {
576 fn CTTypesetterCreateWithAttributedString(string: CFAttributedStringRef) -> CTTypesetterRef;
577
578 fn CTTypesetterSuggestLineBreak(
579 typesetter: CTTypesetterRef,
580 start_index: CFIndex,
581 width: f64,
582 ) -> CFIndex;
583}
584
585impl From<Metrics> for FontMetrics {
586 fn from(metrics: Metrics) -> Self {
587 FontMetrics {
588 units_per_em: metrics.units_per_em,
589 ascent: metrics.ascent,
590 descent: metrics.descent,
591 line_gap: metrics.line_gap,
592 underline_position: metrics.underline_position,
593 underline_thickness: metrics.underline_thickness,
594 cap_height: metrics.cap_height,
595 x_height: metrics.x_height,
596 bounding_box: metrics.bounding_box.into(),
597 }
598 }
599}
600
601impl From<RectF> for Bounds<f32> {
602 fn from(rect: RectF) -> Self {
603 Bounds {
604 origin: point(rect.origin_x(), rect.origin_y()),
605 size: size(rect.width(), rect.height()),
606 }
607 }
608}
609
610impl From<RectI> for Bounds<DevicePixels> {
611 fn from(rect: RectI) -> Self {
612 Bounds {
613 origin: point(DevicePixels(rect.origin_x()), DevicePixels(rect.origin_y())),
614 size: size(DevicePixels(rect.width()), DevicePixels(rect.height())),
615 }
616 }
617}
618
619impl From<Vector2I> for Size<DevicePixels> {
620 fn from(value: Vector2I) -> Self {
621 size(value.x().into(), value.y().into())
622 }
623}
624
625impl From<RectI> for Bounds<i32> {
626 fn from(rect: RectI) -> Self {
627 Bounds {
628 origin: point(rect.origin_x(), rect.origin_y()),
629 size: size(rect.width(), rect.height()),
630 }
631 }
632}
633
634impl From<Point<u32>> for Vector2I {
635 fn from(size: Point<u32>) -> Self {
636 Vector2I::new(size.x as i32, size.y as i32)
637 }
638}
639
640impl From<Vector2F> for Size<f32> {
641 fn from(vec: Vector2F) -> Self {
642 size(vec.x(), vec.y())
643 }
644}
645
646impl From<FontWeight> for FontkitWeight {
647 fn from(value: FontWeight) -> Self {
648 FontkitWeight(value.0)
649 }
650}
651
652impl From<FontStyle> for FontkitStyle {
653 fn from(style: FontStyle) -> Self {
654 match style {
655 FontStyle::Normal => FontkitStyle::Normal,
656 FontStyle::Italic => FontkitStyle::Italic,
657 FontStyle::Oblique => FontkitStyle::Oblique,
658 }
659 }
660}
661
662// Some fonts may have no attributest despite `core_text` requiring them (and panicking).
663// This is the same version as `core_text` has without `expect` calls.
664mod lenient_font_attributes {
665 use core_foundation::{
666 base::{CFRetain, CFType, TCFType},
667 string::{CFString, CFStringRef},
668 };
669 use core_text::font_descriptor::{
670 kCTFontFamilyNameAttribute, CTFontDescriptor, CTFontDescriptorCopyAttribute,
671 };
672
673 pub fn family_name(descriptor: &CTFontDescriptor) -> Option<String> {
674 unsafe { get_string_attribute(descriptor, kCTFontFamilyNameAttribute) }
675 }
676
677 fn get_string_attribute(
678 descriptor: &CTFontDescriptor,
679 attribute: CFStringRef,
680 ) -> Option<String> {
681 unsafe {
682 let value = CTFontDescriptorCopyAttribute(descriptor.as_concrete_TypeRef(), attribute);
683 if value.is_null() {
684 return None;
685 }
686
687 let value = CFType::wrap_under_create_rule(value);
688 assert!(value.instance_of::<CFString>());
689 let s = wrap_under_get_rule(value.as_CFTypeRef() as CFStringRef);
690 Some(s.to_string())
691 }
692 }
693
694 unsafe fn wrap_under_get_rule(reference: CFStringRef) -> CFString {
695 assert!(!reference.is_null(), "Attempted to create a NULL object.");
696 let reference = CFRetain(reference as *const ::std::os::raw::c_void) as CFStringRef;
697 TCFType::wrap_under_create_rule(reference)
698 }
699}
700
701#[cfg(test)]
702mod tests {
703 use crate::{font, px, FontRun, GlyphId, MacTextSystem, PlatformTextSystem};
704
705 #[test]
706 fn test_wrap_line() {
707 let fonts = MacTextSystem::new();
708 let font_id = fonts.font_id(&font("Helvetica")).unwrap();
709
710 let line = "one two three four five\n";
711 let wrap_boundaries = fonts.wrap_line(line, font_id, px(16.), px(64.0));
712 assert_eq!(wrap_boundaries, &["one two ".len(), "one two three ".len()]);
713
714 let line = "aaa ααα ✋✋✋ 🎉🎉🎉\n";
715 let wrap_boundaries = fonts.wrap_line(line, font_id, px(16.), px(64.0));
716 assert_eq!(
717 wrap_boundaries,
718 &["aaa ααα ".len(), "aaa ααα ✋✋✋ ".len(),]
719 );
720 }
721
722 #[test]
723 fn test_layout_line_bom_char() {
724 let fonts = MacTextSystem::new();
725 let font_id = fonts.font_id(&font("Helvetica")).unwrap();
726 let line = "\u{feff}";
727 let mut style = FontRun {
728 font_id,
729 len: line.len(),
730 };
731
732 let layout = fonts.layout_line(line, px(16.), &[style]);
733 assert_eq!(layout.len, line.len());
734 assert!(layout.runs.is_empty());
735
736 let line = "a\u{feff}b";
737 style.len = line.len();
738 let layout = fonts.layout_line(line, px(16.), &[style]);
739 assert_eq!(layout.len, line.len());
740 assert_eq!(layout.runs.len(), 1);
741 assert_eq!(layout.runs[0].glyphs.len(), 2);
742 assert_eq!(layout.runs[0].glyphs[0].id, GlyphId(68u32)); // a
743 // There's no glyph for \u{feff}
744 assert_eq!(layout.runs[0].glyphs[1].id, GlyphId(69u32)); // b
745 }
746}