Reviewing a Merge Request from the terminal

Lately, I have been reviewing Merge Requests with slow (or none at all) internet connections. Because of that, I have started reviewing MRs from my terminal, instead of using Gitlab/Github's web UI. It is faster for me, as I don't need to make requests each time I need to see what changed in each commit.

Here is the workflow I follow when reviewing a MR from my terminal

1. Project high level overview

Reviewing a MR is just a matter of seeing the changes in a branch. My first step is usually seeing where this branch started, how many commits it has and whether it is really behind the target branch or not.

For this, I run git lg. It displays the complete project history as a graph.

git lg is just an alias for a formatted git log. You can alias it by running:

git config --global alias.lg "log --color --graph --pretty=format:'%Cred%h%Creset -%C(yellow)%d%Creset %s %Cgreen(%cr) %C(bold blue)<%an>%Creset' --abbrev-commit --all"

Note: Credits to the author at coderwall.com. I just take credit for adding the --all flag, so that I can see all the branches.

2. Merge Request high level overview

After seeing how this MR relates to the project, I would continue by seeing a summary of what was done in each commit. I would look at each commit's name, description and files changed.

For this, I run:

git log target-branch..feature-branch --name-status --reverse --relative-date

• target-branch..feature-branch will print all the commits that are in feature-branch but not in target-branch.
• --name-status will list the files that were changed in each commit, with a description of the change (renamed, deleted, added).
• --reverse will put the oldest commit at the top and the newest commit at the bottom.
• --relative-date will print how long ago a commit was made (like hours, days, months). Useful for teams in different timezones.

These options will print us something like this:

3. Commit detailed review

Once that I know which files where modified and in which order, I would jump into each commit detail. For that, I use:

git log target-branch..feature-branch --reverse --relative-date --histogram -U20 --color-moved

• --histogram Okey I don't have a good reason for using it. It is just another diff algorithm that I suspect gives better results but it takes slightly longer.
• -U20 Print the previous and the next 20 lines of each changed line. Useful for having more context when reviewing small changes in large code sections.
• --color-moved Display with different colors the blocks of code that were just moved and not changed.

This gives us

4. Merge request diff

Just as a final review, I would generate a diff of the entire MR. For that, I use:

git diff target-branch..feature-branch --histogram -U20 --color-moved

This would produce a complete diff of the merge request

This view is useful when a file was changed through multiple commits.