Phabricator should only generate valid (usable) hashtags

In some situations, we intentionally generate hashtags which are not usable in comment fields. These hashtags are still usable in other contexts, like the "Projects:" field, the search nav, and URLs. The theory is that generating a faithful tag which works in many contexts is useful, and users can always add another convenience tag for comments. So, we do not guarantee that hashtags are usable in comments.

I think the only such intentional case right now is projects with names which end in periods. In comments, we assume a terminal period is always the end of a sentence, and this case seems so rare in project names that the behavior feels reasonable.

The case of internal colons does not seem like a weird special case, though, and we should get this right automatically. In particular, I think we should generate #colon_test for "colon: test" (i.e., forbid colons in slugs).

I have the same issue. May introducing a 'full name' syntax for tags like {#my_cool_project:_bug_returns_2.} be the solution?