Add `print_mode='digits-unicode'` to p-adic numbers

[user202729]

Problem Description

Currently we have

sage: Zp(2, 10, print_mode='digits')(5)
...0000000101

this causes some "issues" with doctest (it matches too liberally)… because ... is a special marker that stands for "arbitrary string".

Proposed Solution

Implement the following

sage: Zp(2, 10, print_mode='digits-unicode')(5)
…0000000101

that uses the Unicode character … instead of 3 ASCII dots ....

Afterwards, the tests can be modified to use this print mode instead of the default one.

There's one precedent of this in src/sage/rings/valuation/limit_valuation.py (although _base_valuation is a private member).

Alternatives Considered

Motivated by looking at https://github.com/sagemath/sage/pull/41194/files

Additional Information

No response

Is there an existing issue for this?

• I have searched the existing issues for a bug report that matches the one I want to file, without success.

[Harkeerat24]

Hello,
I am new to open-source contributions and would like to work on this issue as my first contribution. Could you please assign it to me? Any guidance throughout the process would be greatly appreciated. Thank you!

[r-mb]

Indeed, when I was reviewing this I was afraid about this for the doctests. I wonder if another solution would be to have some keyword (like we do with # random for instance) to ask the tests to check ... as is.

[user202729]

@r-mb bad news, some of the ... are meant to be ellipsis and others are meant to be literal. For example https://github.com/sagemath/sage/pull/41194/files#diff-1f062e54c60f54af565aeb9ad736fe88eea2295d6ad937dfac099054bb481b0aR2676 has an ellipsis-....

elsewhere I use a different hack to check that:

sage/src/sage/doctest/test.py

Line 343 in 5c8d9e9

sage: print(proc.stdout.replace('sage:', 'sage<COLON>').replace('....:', '<DOTSCOLON>'))

But if the problem is any more frequent than a single occurrence, these hacks are unsustainable.

[r-mb]

Oof! Nice catch! Indeed the Unicode approach seems better here.