Fix broken test fixtures: Bold instances missing weightClass#1963
Merged
anthrotype merged 1 commit intomainfrom Apr 16, 2026
Merged
Fix broken test fixtures: Bold instances missing weightClass#1963anthrotype merged 1 commit intomainfrom
anthrotype merged 1 commit intomainfrom
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Several test fixtures have Bold instances with `isBold = 1` but no
explicit `weightClass`. Without it, the heuristic in Instance::new
defaults the wght user-space value to 400 — same as Regular — so both
instances claim the same user coordinate. This makes the fonts
malformed: fontmake/glyphsLib produce degenerate output for them too
(e.g. wght axis collapses to min=max=400, Bold master effectively
discarded). fontc's `add_if_new` happened to mask the problem by
silently dropping the conflicting entry.
Add the correct weightClass to all affected Bold instances:
- WghtVar_Instances.glyphs (g2, g3, g2-pkg, g3-pkg)
- InstancePostscript.glyphs (g2, g3)
- InstanceNoPostscript.glyphs (g3)
Also fix IntermediateLayer.glyphs where "Tall Caps Black" had
interpolationWidth=700 (wght design) but weightClass=Black (wght
user=900), conflicting with "Black" which maps user=900→design=900.
glyphsLib overwrites the mapping to {900: 700}, breaking the axis.
Changed to interpolationWidth=900 for consistency.
cmyr
approved these changes
Apr 16, 2026
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Several test fixtures have Bold instances with
isBold = 1but no explicitweightClass. Without it, the heuristic inInstance::newdefaults the wght user-space value to 400 — same as Regular — so both instances claim the same user coordinate. However, when building these with fontmake/glyphsLib the fonts are malformed with the wght axis collapsing to min=max=400, and the Bold master effectively discarded.fontc's
add_if_newhappens to mask the problem by silently dropping the conflicting entry, but that's not how fontmake and glyphsLib do.I noticed this while working on a fix for #1866.
The fix I am working on (where I match glyphsLib's last-win overwrite semantics) surfaces these malformed test fonts, and I wanted to fix these separately to make the diff less noisy in the next PR.
To recap the changes:
Added the correct weightClass to all affected Bold instances in:
Also fixed IntermediateLayer.glyphs where "Tall Caps Black" had interpolationWidth=700 (wght design) but weightClass=Black (wght user=900), conflicting with "Black" which also maps user=900 -> design=900. glyphsLib would overwrite the mapping to {900: 700}, breaking the axis. Changed to interpolationWidth=900 for consistency.