Issues with odd months when restricting to "day" precision (precisedelta)

What did you do?

I’m trying to provide more precision than “months” when the timedelta is more than 1 month, but I’m finding some issues using precisedelta set to days with a format of %d as seen below. This all seems to stem from the use of 30.5 as a divisor for mod in precisedelta and how it and ngettext interact with floats vs. ints when it comes to pluralize and the display of the days itself. For what it’s worth, the same thing happens at second precision with microseconds present, etc. It seems to be at the minimum_unit where this logic takes place.

What did you expect to happen?

>>> import humanize
>>> import datetime
>>> humanize.precisedelta(datetime.timedelta(days=31), minimum_unit="days", format="%d")
'1 month'
>>> 

>>> import humanize
>>> import datetime
>>> humanize.precisedelta(datetime.timedelta(days=92), minimum_unit="days", format="%d")
'3 months'
>>> 

>>> import humanize
>>> import datetime
>>> humanize.precisedelta(datetime.timedelta(days=32), minimum_unit="days", format="%d")
'1 month and 1 day'
>>>

What actually happened?

>>> import humanize
>>> import datetime
>>> humanize.precisedelta(datetime.timedelta(days=31), minimum_unit="days", format="%d")
'1 month and 0 days'
>>> 

>>> import humanize
>>> import datetime
>>> humanize.precisedelta(datetime.timedelta(days=92), minimum_unit="days", format="%d")
'3 month and 0 days'
>>> 

>>> import humanize
>>> import datetime
>>> humanize.precisedelta(datetime.timedelta(days=32), minimum_unit="days", format="%d")
'1 month and 1 days'
>>>

What versions are you using?

• OS: Windows, Ubuntu 20.04
• Python: 3.8.10
• Humanize: 4.1.0

Please include code that reproduces the issue (included in expected, actually happened above)

[eldipa]

Actually truncate=False is what you want most of the time. Consider the following example:

>>> humanize.precisedelta(datetime.timedelta(days=31), minimum_unit='days')
'1 month and 0.50 days'

precisedelta tries to not loose any precision so it returns 0.50 (see doc

Now, if the user wants to use a interger-like formatting for the fractional part like "%d", only then it makes sense to use truncate=True because otherwise you will get a 0 units:

>>> humanize.precisedelta(datetime.timedelta(days=31), minimum_unit='days', format='%d')
'1 month and 0 days'

>>> humanize.precisedelta(datetime.timedelta(days=31), minimum_unit='days', format='%d', truncate=True)
'1 month'

See doc and doc

Also, not very sure if truncate should be public… it feels a hack: the algorithm is okay but how to enable it is what it looks hacky. For example, assuming format != '%d', is any useful case to set truncate=True. I don’t think so.

In an ideal world truncate should be automatically set from format but not sure how to do it without doing if format == '%d' ... (I’m not fully convinced to that, it is fragile). For example, for format = '%i' you have to truncate=True also.

[shazib-summar]

@eldipa the truncate parameter seems to be removed from the precisedelta func. Any ideas how I can truncate the output without it?