Color merge commits differently in Git log output?

Question

I currently format my Git log using the following pretty definition:

[format]
  pretty = format:%C(normal)%h %C(blue)%s %C(yellow)[%an]%C(reset)

This results in the output below:

Most of the time, I don't need to pay much attention to merge commits, so I have an alias that includes the --no-merges flag by default:

I would actually prefer for merge commit log entries to always be present but be colored differently from non-merge commit log entries (so I can train my eye to skip them by default).

Is it possible to color merge commit log entries differently from non-merge commit log entries? If so, how do I achieve that?

Answer 1

You can achieve this with a git alias, using eg. sed.

[alias]
    logo = "!logo(){ git log --pretty='format:<<%p>>%H %s %D' $@ | sed -e 's/<<[^ ]* [^ ]*\\( [^ ]*\\)*>>/\\x1B[36m/' -e 's/<<[^ ]*>>//' -e 's/$/\\x1B[0m/' | less -FRSX;  }; logo"

The %p specifier prints all the parents of the commit. The sed patterns recognize when there is more than one parent and replace that case with a color code. The color is reset at the end of each line.

The function wrapper and less give you the capability to pass git log parameters and restore paging, respectively.