Prune listings of variable fonts

Show only one entry per style per variable font as identified by path

kitty/core_text.m

@@ -845,10 +845,13 @@ get_variable_data(CTFace *self) {
     RAII_CoreFoundation(CFArrayRef, descriptors, CTFontCollectionCreateMatchingFontDescriptors(collection));
     RAII_PyObject(named_styles, PyTuple_New(CFArrayGetCount(descriptors)));
     Py_ssize_t actual_num = 0;
+    RAII_CoreFoundation(CFURLRef, url, CTFontCopyAttribute(self->ct_font, kCTFontURLAttribute));
     for (CFIndex i = 0; i < CFArrayGetCount(descriptors); i++) {
         CTFontDescriptorRef descriptor = (CTFontDescriptorRef)CFArrayGetValueAtIndex(descriptors, i);
         RAII_CoreFoundation(CFDictionaryRef, variation, CTFontDescriptorCopyAttribute(descriptor, kCTFontVariationAttribute));
         if (!variation) continue;
+        RAII_CoreFoundation(CFURLRef, candidate_url, CTFontDescriptorCopyAttribute(descriptor, kCTFontURLAttribute));
+        if (!CFEqual(url, candidate_url)) continue;
         RAII_CoreFoundation(CFStringRef, style, CTFontDescriptorCopyAttribute(descriptor, kCTFontStyleNameAttribute));
         RAII_CoreFoundation(CFStringRef, psname, CTFontDescriptorCopyAttribute(descriptor, kCTFontNameAttribute));
         RAII_PyObject(axis_values, PyDict_New());

kitty/fonts/core_text.py

@@ -118,6 +118,26 @@ def font_for_family(family: str) -> Tuple[CoreTextFont, bool, bool]:
 
 
 def get_variable_data_for_descriptor(f: ListedFont) -> VariableData:
+    return CTFace(descriptor=descriptor(f)).get_variable_data()
+
+
+def descriptor(f: ListedFont) -> CoreTextFont:
     d = f['descriptor']
     assert d['descriptor_type'] == 'core_text'
-    return CTFace(descriptor=d).get_variable_data()
+    return d
+
+
+def prune_family_group(g: List[ListedFont]) -> List[ListedFont]:
+    # CoreText returns a separate font for every style in the variable font, so
+    # merge them.
+    variable_paths = {descriptor(f)['path']: False for f in g if f['is_variable']}
+    if not variable_paths:
+        return g
+    def is_ok(d: CoreTextFont) -> bool:
+        if d['path'] not in variable_paths:
+            return True
+        if not variable_paths[d['path']]:
+            variable_paths[d['path']] = True
+            return True
+        return False
+    return [x for x in g if is_ok(descriptor(x))]

kitty/fonts/fontconfig.py

@@ -177,7 +177,22 @@ def font_for_family(family: str) -> Tuple[FontConfigPattern, bool, bool]:
     return ans, ans.get('weight', 0) >= FC_WEIGHT_BOLD, ans.get('slant', FC_SLANT_ROMAN) != FC_SLANT_ROMAN
 
 
-def get_variable_data_for_descriptor(f: ListedFont) -> VariableData:
+def descriptor(f: ListedFont) -> FontConfigPattern:
     d = f['descriptor']
     assert d['descriptor_type'] == 'fontconfig'
-    return Face(descriptor=d).get_variable_data()
+    return d
+
+
+def get_variable_data_for_descriptor(f: ListedFont) -> VariableData:
+    return Face(descriptor=descriptor(f)).get_variable_data()
+
+
+def prune_family_group(g: List[ListedFont]) -> List[ListedFont]:
+    # fontconfig creates dummy entries for named styles in variable fonts, prune them
+    variable_paths = {descriptor(f)['path'] for f in g if f['is_variable']}
+    if not variable_paths:
+        return g
+    def is_ok(d: FontConfigPattern) -> bool:
+        return d['variable'] or d['path'] not in variable_paths
+
+    return [x for x in g if is_ok(descriptor(x))]

kitty/fonts/list.py

@@ -11,9 +11,9 @@ from kitty.types import run_once
 from . import ListedFont
 
 if is_macos:
-    from .core_text import get_variable_data_for_descriptor, list_fonts
+    from .core_text import get_variable_data_for_descriptor, list_fonts, prune_family_group
 else:
-    from .fontconfig import get_variable_data_for_descriptor, list_fonts
+    from .fontconfig import get_variable_data_for_descriptor, list_fonts, prune_family_group
 
 
 @run_once
@@ -54,14 +54,12 @@ def create_family_groups(monospaced: bool = True) -> Dict[str, List[ListedFont]]
     for f in list_fonts():
         if not monospaced or f['is_monospace']:
             g.setdefault(f['family'], []).append(f)
-    return g
+    return {k: prune_family_group(v) for k, v in g.items()}
 
 
 def show_variable(f: ListedFont, psnames: bool) -> None:
     vd = get_variable_data_for_descriptor(f)
-    p = italic(f['full_name'])
-    if psnames and f['postscript_name']:
-        p += f' ({f["postscript_name"]})'
+    p = italic(f['family'])
     p = f"{p} {variable_font_label('Variable font')}"
     print(indented(p))
     print(indented(variable_font_label('Axes of variation'), level=2))