I was wondering the same thing, and I finally got this working. I think the problem was with the attrs package. One of the errors made it look like I needed attr (no 's'), but that is a different unrelated package.
I installed black with Stash pip, as well as attrs and any other package it needed, until I could run black.py without errors.
I put together this little script to format a document in the editor. I'm sure there's a better way to do it, but this seems to work beautifully when added to the tools menu in Pythonista.
#!/usr/bin/env python3
"""Format editor contents/selection in Pythonista with Black formatter."""
import editor
import black
import console
import time
# Options
LINE_LEN = 88 # Default: 88
FAST = False # True = skip syntax check
# Get text and selection
text = editor.get_text()
start, end = editor.get_selection()
selection = text[start:end]
if len(selection) > 0:
raw_text = selection
else:
raw_text = text
try:
start_tm = time.time()
formatted = black.format_file_contents(
raw_text, line_length=LINE_LEN, fast=int(FAST)
)
except black.NothingChanged:
console.hud_alert(
f"No formatting needed! ({time.time() - start_tm:.4f}s)", "success"
)
except Exception as err:
console.hud_alert(err, "error")
else:
new_text = formatted[:-1]
if len(selection) > 0:
editor.replace_text(start, end, new_text)
editor.set_selection(start, start + len(new_text))
else:
editor.replace_text(0, len(text), new_text)
editor.set_selection(start, end)
console.hud_alert(
f"Reformatted! ({time.time() - start_tm:.4f}s)", "success")
