“TypeError: 'float' object cannot be interpreted as an integer” error on Python 3.10

[win98se]

Command line: ./monospacifier.py --references ./sources/references/* --inputs ./sources/inputs/* --save-to ./fonts --copy-metrics --merge

Error log:

Traceback (most recent call last):
  File "/home/lcw/fck/./monospacifier.py", line 309, in <module>
    main()
  File "/home/lcw/fck/./monospacifier.py", line 293, in main
    results = list(process_fonts(args.references, args.inputs,
  File "/home/lcw/fck/./monospacifier.py", line 284, in process_fonts
    path = make_monospace(reference, fallback, gscaler, save_to, copy_metrics, renames)
  File "/home/lcw/fck/./monospacifier.py", line 227, in make_monospace
    fscaler.scale_glyphs(gscaler)
  File "/home/lcw/fck/./monospacifier.py", line 172, in scale_glyphs
    scaler.scale(glyph)
  File "/home/lcw/fck/./monospacifier.py", line 124, in scale
    GlyphScaler.set_width(glyph, self.cell_width)
  File "/home/lcw/fck/./monospacifier.py", line 66, in set_width
    glyph.left_side_bearing += delta / 2
TypeError: 'float' object cannot be interpreted as an integer

Seems to be related with #30.

[cpitclaudel]

You posted two backtraces, one with math.ceil and the other not; which one is right?

In any case, the fix looks like it would be to wrap a call to int around the division; would you submit a PR?

[win98se]

You posted two backtraces, one with math.ceil and the other not; which one is right?

The one without is the right one; The one with is from #30, which doesn't work here as well...

In any case, the fix looks like it would be to wrap a call to int around the division; would you submit a PR?

In my understanding, should it look like glyph.left_side_bearing += int(delta / 2)? Even if so, it doesn't work too.

[cpitclaudel]

Even if so, it doesn't work too.

Same error?

[win98se]

Yes, same error, unfortunately.

[cpitclaudel]

Sorry to hear this. Unfortunately, I'm not going to have time to debug this in the short term. I hope someone else can chime in.

[xtevenx]

It seems like a problem with fontforge itself since setting glyph.left_side_bearing to any float raises TypeError despite it being valid. Heck, since it's a float when loaded from a font face, trying to set it as itself (glyph.left_side_bearing = glyph.left_side_bearing) also raises TypeError.

[cpitclaudel]

Can we report a bug to the Fontforge folks?

[PatienceAllergy]

I'm still not sure why, but this fixed it for me:

        glyph.left_side_bearing = int(glyph.left_side_bearing + delta / 2)
        glyph.right_side_bearing = int(glyph.right_side_bearing + delta - glyph.left_side_bearing)

[cpitclaudel]

@PatienceAllergy that makes sense to me, though I suspect you'd want int(math.round(…)) instead. I was surprised that @win98se said it didn't work, but looking at the code again it makes sense that it did not work: glyph.left_side_bearing += int(delta / 2) is the same as glyph.left_side_bearing = glyph.left_side_bearing + int(delta / 2), which is not right (it still stored a float). Your version casts to int after computing the new value, which is good.

Would you be OK with preparing a pull request, with the rounding added?

Also, it would be great if someone could make a bug report in the fontforge tracker.

[PatienceAllergy]

Would you be OK with preparing a pull request, with the rounding added?

I'll give it a go. I've never done one before. So, as long as you're not in a hurry, I'll look at it tomorrow arvo (about 18hrs from now).

[PatienceAllergy]

Would you be OK with preparing a pull request, with the rounding added?

Done! Well now I know how to do that. I also explicitly did a test font conversion to be 100% sure.

Also, it would be great if someone could make a bug report in the fontforge tracker.

I'm not sure I understand the problem well enough, was my explanation on the pull request right?

[win98se]

I was surprised that @win98se said it didn't work, but looking at the code again it makes sense that it did not work: glyph.left_side_bearing += int(delta / 2) is the same as glyph.left_side_bearing = glyph.left_side_bearing + int(delta / 2), which is not right (it still stored a float).

This is indeed my oversight, my apologies.

---

@PatienceAllergy Thank you for making a pull request at #34, your logics solved it; Also @cpitclaudel meant that we should create an issue at https://github.com/fontforge/fontforge/issues, but my wording is specifically bad - I hope you may help in creating one.

I'm not sure I understand the problem well enough, was my explanation on the pull request right?

In my opinion, yes.

[BeeGass]

Is there some reason why this hasnt been merged to master? It appears the pull request is fully functional and ready, no?