"exact" modifier does not seem to work (at least when used in a revset within a describe() expression)

[AngelEzquerra]

Description

Steps to Reproduce the Problem

1. jj new -m "my_unique_test_description"
2. jj log -r "describe(exact:"my_unique_test_description")
3. Returns no revisions

Expected Behavior

It should return the revisions exactly matching "my_unique_test_description" (normally it should just be one)

Actual Behavior

No revisions are matched

Specifications

• Platform: Windows
• Version: 0.24

[joyously]

Does exact mean that the entire content matches exactly or that an exact match is contained in the content?

[scott2000]

I've run into this before. I think it's because technically, the description ends with a newline if it's non-empty. So description(exact:"") matches empty description, and description(exact:"my_unique_test_description\n") matches "my_unique_test_description".

[yuja]

I've run into this before. I think it's because technically, the description ends with a newline if it's non-empty. So description(exact:"") matches empty description, and description(exact:"my_unique_test_description\n") matches "my_unique_test_description".

That's probably it. I think the revset doc can be updated.

[ilyagr]

Another confusing thing is that description(exact:'my_unique_test_description\n') doesn't work. A literal newline like

jj log -r 'description(exact:\'test
\')'

or

jj log -r "description(exact:'test
')"

does work (in fish at least).

Perhaps description should match both with and without a trailing \n, since jj already adds the \n automatically? I suppose we could have strict_description that acts differently. This isn't perfect, but perhaps it's better than the status quo. Or can we think of something even better?

I suppose there could be a version of exact that trims whitespace.

[yuja]

Well, '' means raw string (i.e disable escapes).

I don't think exact match on description is useful (except for exact:"".) It's probably better to suggest regex for line-based matching than adding special case for description().

[emilazy]

What may be useful is having a query (and template?) for only the subject line of a description, which can be fairly useful to search exactly (e.g. commit subjects mentioned in emails), and could naturally strip the trailing newline.

[AngelEzquerra]

I don't think exact match on description is useful (except for exact:"".) It's probably better to suggest regex for line-based matching than adding special case for description()

I think it could be quite useful if you use certain specific descriptions for certain revisions (e.g. CI/CD, etc).
In any case, the current behavior is very surprising. If you set the description to "test" by using jj describe -m "test" one would expect to find that specific revision by doing `jj log -r "description(exact:'test')", wouldn't it? The fact that jj adds a trailing '\n' should not leak to the UX, IMHO.

What may be useful is having a query (and template?) for only the subject line of a description, which can be fairly useful to search exactly (e.g. commit subjects mentioned in emails), and could naturally strip the trailing newline.

FWIW mercurial does have a "matching" function that can take "summary" as its "field" argument, which looks for the first line of each commit message.

[martinvonz]

FWIW, jj describe -m has added since PR #936. git commit -m seems to do the same thing but hg commit -m does not.