On Gitlab, how to compare a file of two different commits

Question

On GitLab, how to compare a file of two different commits? I know that that on command line git, the command is:

git diff commit1 commit12 -- file_name 

What is the link format to do this on GitLab?

See my related question

Answer 1

It will compare commits, you will be able to find file in list.

1. go to Repository > Compare
2. paste this url: https://gitlab.com/$USER/$REPO/compare?from=$SHA1&to=$SHA2
3. hit enter (notice: gitlab will set 'Source' and 'Target' properly)
4. click button 'compare'

Answer 2

It appears the direct URL for compare is as follows

# compare URL, where ref_source and ref_target can be commit SHA, tag, or branch https://${gitlab_host}/${repo_path}/-/compare/${ref_target}...${ref_source}  # tag example 1, comparing tag v1.5.1 to master https://${gitlab_host}/${repo_path}/-/compare/v1.5.1...master  # tag example 2, comparing tag v1.5.1 to tag v1.5.2 https://${gitlab_host}/${repo_path}/-/compare/v1.5.1...v1.5.2  # commit example 1, comparing commit SHA to master https://${gitlab_host}/${repo_path}/-/compare/f6098082f...master  # commit example 2, comparing commit SHA to another commit SHA https://${gitlab_host}/${repo_path}/-/compare/f6098082f...2b8daf28 

To compare a single file across two commits, one needs to get a blob id of the file first, and append it to the compare url following a octothorp (#); gotta find a way to get that id though

# compare URL, where ref_source and ref_target can be commit SHA, tag, or branch, and file_blob https://${gitlab_host}/${repo_path}/-/compare/${ref_target}...${ref_source}#${file_blob} 

And the compare UI can be reached at https://${gitlab_host}/${repo_path}/-/compare, where you can select source and target refs via drop-down.