Option to show whitespace and tab characters in file and diff view

[Ryan J Ollos]

The TortoiseSVN diff view has the option to show whitespace and tab characters. It would be useful to have an option to do the same in the Trac file and diff views.

[Ryan J Ollos]

​pygments.filters.VisibleWhitespaceFilter provides a whitespace annotation similar to TortoiseSVN's diff viewer.

Possible TODO In setup.py, the minimum Pygments version would need to be bumped from 0.6 to 0.8.

[Jun Omae]

MIDDLE DOT (U+00B7) and PILCROW SIGN (U+00B6) are defined as ambiguous characters, according to ​UAX #11: East Asian Width. Then, the characters are treated and rendered as double-width for 1 character in CJK environments.

>>> from unicodedata import east_asian_width
>>> east_asian_width(u'\u00b7')
'A'
>>> east_asian_width(u'\u00bb')
'N'
>>> east_asian_width(u'\u00b6')
'A'
>>>

We should use single-width characters rather than the default if the filter is used.

[Ryan J Ollos]

I'll have a patch ready soon that includes the suggestions from comment:2. Some early thoughts:

• We'll need to add options to a form in the source browser for:
  • Visible whitespace
  • Visible new lines

Presumably the options should only be present when Pygments is installed.

• Code blocks could have keyword arguments whitespace=visible, newlines=visible (similarly, we recently added lineno keyword arguments in #10834).
• The Changeset view doesn't appear to use PygmentsRenderer. I've long considered this to be a drawback and wondered whether we can use syntax highlighting in the changeset view, perhaps with lighter colors for the added/deleted highlighting.

[Christian Boos]

I think using Pygments in the changeset view is going to be challenging. You'd need to render both the full old and full new versions, and then retrieve the appropriate lines. Otherwise, lacking the appropriate context, the chances that things will get wrongly highlighted are high.

[Ryan J Ollos]

Replying to cboos:

I think using Pygments in the changeset view is going to be challenging. You'd need to render both the full old and full new versions, and then retrieve the appropriate lines. Otherwise, lacking the appropriate context, the chances that things will get wrongly highlighted are high.

We should maybe try it then for just the case Show the changes in full context.

[Ryan J Ollos]

Replying to jomae:

We should use single-width characters rather than the default if the filter is used.

Do you have a suggestion for which characters to use?

[Jun Omae]

Do you have a suggestion for which characters to use?

Sorry for confusing about it. I tried the default characters in pre element with Internet Explorer 11 on Japanese Environment. These characters seems to be no problems even ambiguous characters. I consider that using default characters lead no problems. See whitespace-chars-on-ie11-ja.png​ and demo-1.0/ticket/3726.

[Ryan J Ollos]

Replying to rjollos:

• The Changeset view doesn't appear to use PygmentsRenderer. I've long considered this to be a drawback and wondered whether we can use syntax highlighting in the changeset view, perhaps with lighter colors for the added/deleted highlighting.

​Here is some inspiration.

[Ryan J Ollos]

Narrowing focus for 1.1.4.

[Ryan J Ollos]

Milestone renamed

[anonymous]

+1 for visible whitespace and newlines! (If possible also indicate Windows newlines CR/LF etc.)