仅通过合并基础和合并提交过滤 git log

Question

My git repository has multiple branches. I'd like to see a branch graph which describe how these branches divided and merged.

Consider this graph:

$ git log --graph --all --oneline
*   eac03d9 (develop) Merge branch 'release/xxx' into develop
|\
* \   d94a368 Merge branch 'feature/xxx' into develop
|\ \
| * | 624b398 feat: xxx
| * | 9a87641 feat: xxx
| | | *   6bfbc30 (master) Merge branch 'release/xxx'
| | | |\
| | | |/
| | |/|
| | * | 8d85380 (release/xxx) fix: xxx
| | * | f7e9ef9 fix: xxx
| |/ /
|/| |
* | | 733751e feat: xxx
* | | d5efb9e feat: xxx
|/ /
* | 5ceb217 feat: xxx
* | ea70adf feat: xxx
* | eeff2a3 feat: xxx
|/
* b4b3db0 root

It contains many feat: xxx and fix: xxx commits, which i'd like to hidden. I'm looking for some git log options to filter only merge-base and merge commits.

For example:

*   eac03d9 (develop) Merge branch 'release/xxx' into develop
|\
* \   d94a368 Merge branch 'feature/xxx' into develop
|\ \
| | | *   6bfbc30 (master) Merge branch 'release/xxx'
| | | |\
| | | |/
| | |/|
| | * | 8d85380 (release/xxx) fix: xxx
| |/ /
|/| |
|/ /
|/
* b4b3db0 root

Answer 1

I guess this should work for you.
git log | grep -vE "[a-zA-Z0-9] feat: xxx|[a-zA-Z0-9] fix: xxx"


Explanation :

1)
| -> Pipe will provide output of command at the LHS to RHS
Example : git log | grep "fix" git log | grep "fix" will provide output of git log to grep command

2)
grep -vE -> v for avoiding / excluding , and E for adding more arguments within single grep (or I can say it as or , that is grep "a|b" means show output if there is a or b

3)
[a-zA-Z0-9] -> is a regex to avoid special character (see here : https://regex101.com/r/DXmsTi/1 )


Update:

git log |  grep -E " Merge branch |\(release/"