Add better log when there is a mismatch between the font request and the one we got

Author: moi15moi

font_collector/__main__.py

@@ -9,9 +9,9 @@
     FontCollection,
     FontFile,
     FontLoader,
-    FontResult,
     FontSelectionStrategyLibass,
-    VariableFontFace
+    VariableFontFace,
+    font_weight_to_name
 )
 from .mkvpropedit import Mkvpropedit
 from .parse_arguments import parse_arguments
@@ -39,7 +39,7 @@ def main() -> None:
         file_handler.setFormatter(_handler.formatter)
         _logger.addHandler(file_handler)
         _logger.info(f"{Path.cwd()}>{' '.join(argv)}")
-    
+
     try:
         fonts_file_found: set[FontFile] = set()
         additional_fonts = FontLoader.load_additional_fonts(additional_fonts_path)
@@ -65,11 +65,11 @@ def main() -> None:
                     _logger.error(f"Used on lines: {' '.join(str(line) for line in usage_data.ordered_lines)}")
                 else:
                     if font_result.need_faux_bold:
-                        _logger.warning(f"Faux bold used for '{style.fontname}'.")
+                        _logger.warning(f"Faux bold used for '{style.fontname}' (requested weight {style.weight}-{(font_weight_to_name(style.weight))}, got {font_result.font_face.weight}-{(font_weight_to_name(font_result.font_face.weight))}).")
                     elif font_result.mismatch_bold:
-                        _logger.warning(f"'{style.fontname}' does not have a bold variant.")
+                        _logger.warning(f"Mismatched weight for '{style.fontname}' (requested weight {style.weight}-{(font_weight_to_name(style.weight))}, got {font_result.font_face.weight}-{(font_weight_to_name(font_result.font_face.weight))}).")
                     if font_result.mismatch_italic:
-                        _logger.warning(f"'{style.fontname}' does not have an italic variant.")
+                        _logger.warning(f"Mismatched italic for '{style.fontname}' (requested {'non-' if style.italic else ''}italic, got {'non-' if font_result.font_face.is_italic else ''}italic).")
 
                     if font_result.need_faux_bold or font_result.mismatch_bold or font_result.mismatch_italic:
                         _logger.warning(f"Used on lines: {' '.join(str(line) for line in usage_data.ordered_lines)}")

font_collector/font/__init__.py

@@ -10,3 +10,4 @@
 from .font_type import *
 from .name import *
 from .variable_font_face import *
+from .weight_helper import *

font_collector/font/weight_helper.py

@@ -0,0 +1,29 @@
+from __future__ import annotations
+
+__all__ = ["font_weight_to_name"]
+
+def font_weight_to_name(weight: int) -> str:
+    """
+    Args:
+        weight: The weight of a font as defined in usWeightClass:. https://learn.microsoft.com/en-us/typography/opentype/spec/os2#usweightclass
+    Returns:
+        The name corresponding to the weight.
+    """
+    if weight <= 150:
+        return "Thin"
+    elif 151 <= weight <= 250:
+        return "ExtraLight"
+    elif 251 <= weight <= 350:
+        return "Light"
+    elif 351 <= weight <= 450:
+        return "Regular"
+    elif 451 <= weight <= 550:
+        return "Medium"
+    elif 551 <= weight <= 650:
+        return "SemiBold"
+    elif 651 <= weight <= 750:
+        return "Bold"
+    elif 751 <= weight <= 850:
+        return "ExtraBold"
+    else:
+        return "Black"

tests/font/test_weight_helper.py

@@ -0,0 +1,35 @@
+import pytest
+from font_collector import font_weight_to_name
+
+
+@pytest.mark.parametrize("weight,expected", [
+    (50, "Thin"),
+    (100, "Thin"),
+    (150, "Thin"),
+    (151, "ExtraLight"),
+    (200, "ExtraLight"),
+    (250, "ExtraLight"),
+    (251, "Light"),
+    (300, "Light"),
+    (350, "Light"),
+    (351, "Regular"),
+    (400, "Regular"),
+    (450, "Regular"),
+    (451, "Medium"),
+    (500, "Medium"),
+    (550, "Medium"),
+    (551, "SemiBold"),
+    (600, "SemiBold"),
+    (650, "SemiBold"),
+    (651, "Bold"),
+    (700, "Bold"),
+    (750, "Bold"),
+    (751, "ExtraBold"),
+    (800, "ExtraBold"),
+    (850, "ExtraBold"),
+    (851, "Black"),
+    (900, "Black"),
+    (1000, "Black"),
+])
+def test_font_weight_to_name(weight, expected):
+    assert font_weight_to_name(weight) == expected