History browser: which version changed a tag (git blame)?

[simon04]

The tag table of the history browser could display for each line (for each key) in which version this value has been changed, similar to ​git blame.

[simon04]

In 17886/josm:

see #20879 - Extract TagTableModel.getDiffItemType

[simon04]

In 17887/josm:

fix #20879 - History browser: which version changed a tag (git blame)?

[simon04]

Replying to gaben in ticket:20880#comment:6:

If the modifications not uploaded yet, the version number is messed up. After upload the since column becomes empty.

[gaben]

Oh sorry, I reopened the wrong ticket.

Aside from the bug, it's a nice feature I already like it, thank you! :D

[simon04]

In 17903/josm:

see #20879 - History browser: display version "*" if tag change has not been committed

[skyper]

I like the new feature but it can be irritating if a tag was added more than once. Right now there is no differences made and only the last version is shown. Especially, in cases of reverts and undelete actions this does not work well.

[gaben]

I have the same feeling but can't figure out a nice way to present it to the GUI. How do you want to see it?

[skyper]

A different text color or background color could be used if the tag was not added for the first time.

If I get it right, #20880 and this ticket could be tied together and the version number could get the background from #20880. Then there would be enough space for three or four different colors.

[simon04]

Idea: we could add two colour gutters:

• gutter to the left of keys shows when the key was first added
• gutter to the right of values shows when the value was last changed (added in r17887 and r17890)

[simon04]

In 17904/josm:

see #20879 - ​https://errorprone.info/bugpattern/FallThrough