load_glyphs() not working in v1.5.2 (worked in v1.5.1)

[anecdata]

Tested on Espressif, SAMD51, SAMD21, RP2040. PyPortal demo:

Adafruit CircuitPython 7.1.0-beta.0 on 2021-11-12; Adafruit PyPortal with samd51j20
>>> 
>>> from adafruit_bitmap_font import bitmap_font
>>> 
>>> bitmap_font.__version__
'1.5.1'
>>> 
>>> # from https://learn.adafruit.com/pyportal-alarm-clock/code-tour
>>> time_font = bitmap_font.load_font('/fonts/Arial-12.bdf')
>>> time_font.load_glyphs(b'0123456789:')
>>> 

Replace adafruit_bitmap_font v1.5.1 with adafruit_bitmap_font v1.5.2:

Adafruit CircuitPython 7.1.0-beta.0 on 2021-11-12; Adafruit PyPortal with samd51j20
>>> 
>>> from adafruit_bitmap_font import bitmap_font
>>> 
>>> bitmap_font.__version__
'1.5.2'
>>> 
>>> # from https://learn.adafruit.com/pyportal-alarm-clock/code-tour
>>> time_font = bitmap_font.load_font('/fonts/Arial-12.bdf')
>>> time_font.load_glyphs(b'0123456789:')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/lib/adafruit_bitmap_font/bdf.py", line 142, in load_glyphs
OSError: [Errno 22] Invalid argument
>>> 

[FoamyGuy]

It looks to me like the code at line 142 is assuming that self.file is an opened file instance.

Adafruit_CircuitPython_Bitmap_Font/adafruit_bitmap_font/bdf.py

Line 142 in a3272e2

line = self.file.readline()

tracing back up a bit in the library the file is coming ultimately from here:

Adafruit_CircuitPython_Bitmap_Font/adafruit_bitmap_font/bitmap_font.py

Lines 36 to 41 in a3272e2

	with open(filename, "rb") as font_file:
	first_four = font_file.read(4)
	if filename.endswith("bdf") and first_four == b"STAR":
	from . import bdf
	return bdf.BDF(font_file, bitmap)

I'm not super familiar with the lifecycle of things that use the with: context processor. Is it possible that the return and initializer happening on the same line is resulting in font_file getting closed automatically by the end of the with block before it has the chance to be used for reading inside of the load_glyphs() function?

[FoamyGuy]

I do think the issue is that the file is being closed before load_glyphs() can do anything with it. I verified the same error with this minimal reproducer:

>>> f = open("boot_out.txt", "r")
>>> print(f.readline())
Adafruit CircuitPython 7.0.0-alpha.5 on 2021-07-21; Adafruit FunHouse with ESP32S2

>>> f.close()
>>> f.seek(0)
84
>>> print(f.readline())
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
OSError: [Errno 22] Invalid argument

[anecdata]

I think you're right, the file diff seemed to point to that too.

[tannewt]

We should probably switch this to a filename as well.

[jposada202020]

Is there any work to be done here? or #52 solved the issue. Happy to help if needed :)

[anecdata]

As far as I know, this was fixed in 1.5.3, and versions starting then have been loading fonts and glyphs fine.

[jposada202020]

I think I will test it with https://github.com/adafruit/Adafruit_CircuitPython_Display_Text/blob/main/examples/display_text_advance_example.py , and if everything goes well and you agree Ill close the issue :)

[jposada202020]

You were right, no issues detected. Tested on

Adafruit CircuitPython 8.0.0 on 2023-02-06; Adafruit PyPortal Titano with samd51j20

Using https://github.com/adafruit/Adafruit_CircuitPython_Display_Text/blob/main/examples/display_text_advance_example.py

LGTM thanks