Get default fetch remote from configuration

[cruessler]

This PR is in response to #1093. It changes how GitUI gets the remote to fetch from.

This is a follow-up PR to #2156 which added similar behaviour for pushing.

It changes the following:

• It adds get_default_remote_for_fetch_in_repo which reads git configuration related to remote repositories. It first reads branch.<name>.remote. This is according to the docs.

I followed the checklist:

• I added unittests
• I ran make check without errors
• I tested the overall application
• I added an appropriate item to the changelog

Test fetch/pull behavior in status tab:

• no upstream branch configured
  If no upstream branch is configured, you still can’t fetch from a remote if you have renamed origin to something else, e. g. non-origin. I think this is the right thing to do for the time being. As far as I’m aware, we want to provide a UI allowing users to choose a branch to fetch from in the future. man git-fetch says: “When no remote is specified, by default the origin remote will be used, unless there’s an upstream branch configured for the current branch.”
• upstream branch configured, branch.<>.remote is set

[cruessler]

@extrawurst This PR is now ready for review. It is hopefully a small step towards making the error message git: inconclusive remotes disappear. 😄

Once it is merged, GitUI should respect configured remote branches for fetching and pushing. We could then start implementing a fallback for when no remote branch is configured. I’m also thinking about creating a couple good first issues in order to deduplicate/clean up some of the new code.

[extrawurst]

Awesome!! I am going to review it tomorrow !

[extrawurst]

does this fix #1093 now?

[extrawurst]

lgtm. just one thing:

I’m also thinking about creating a couple good first issues in order to deduplicate/clean up some of the new code.

can you mark the places with //TODO: <description> ?

[extrawurst]

@cruessler

does this fix #1093 now?

if so, lets mark that in the changelog

[cruessler]

@cruessler

does this fix #1093 now?

if so, lets mark that in the changelog

I’ll have a look tomorrow on the train!

[cruessler]

@cruessler

does this fix #1093 now?

if so, lets mark that in the changelog

As far as I can tell, this fixes #1093. I’ve updated the changelog entry. This is how I prepared the repository before I tested the branch:

❯ git remote rename origin non-origin

❯ git remote
non-origin
upstream

❯ git push non-origin
[…]
 * [new branch]      test-remotes -> test-remotes
branch 'test-remotes' set up to track 'non-origin/test-remotes'.

❯ git remote set-url non-origin git@github.com:cruessler/gitui.git

❯ git config --list | grep non-origin
remote.non-origin.url=git@github.com:cruessler/gitui.git
remote.non-origin.fetch=+refs/heads/*:refs/remotes/non-origin/*
branch.test-remotes.remote=non-origin

I was able to successfully pull in this setup. Since git automatically sets up branch.<>.remote, the only reason this does not fix the issue would be additional local configuration. Or something else I don’t know yet. 😄