git remote: only check for an existing remote in local config when adding/renaming

CHANGELOG.md

@@ -125,6 +125,10 @@ should not be broken.
   date.
   [#8007](https://github.com/jj-vcs/jj/issues/8007)
 
+* `jj git clone` now succeeds if configuration for the current remote exists
+  in a global config file.
+  [#7820](https://github.com/jj-vcs/jj/issues/7820)
+
 ## [0.35.0] - 2025-11-05
 
 ### Release highlights

cli/tests/test_git_remotes.rs

@@ -553,41 +553,23 @@ fn test_git_remote_with_global_git_remote_config() {
     // Complete remotes from the global configuration are listed.
     //
     // `git remote -v` lists all remotes from the global configuration,
-    // even incomplete ones like `origin`. This is inconsistent with
-    // the other `git remote` commands, which ignore the global
-    // configuration (even `git remote get-url`).
+    // even incomplete ones like `origin`. Confusingly, these remotes
+    // are ignored by other `git remote` commands (even `git remote get-url`).
+    //
+    // This behavior is replicated by `jj git remote`. `jj git remote list`
+    // will list remotes from both global and local configuration, but other
+    // commands like `rename` will ignore the global configuration.
     insta::assert_snapshot!(output, @r"
     foo htps://example.com/repo/foo
     [EOF]
     ");
 
     let output = work_dir.run_jj(["git", "remote", "rename", "foo", "bar"]);
-    // Divergence from Git: we read the remote from the global
-    // configuration and write it back out. Git will use the global
-    // configuration for commands like `git remote -v`, `git fetch`,
-    // and `git push`, but `git remote rename`, `git remote remove`,
-    // `git remote set-url`, etc., will ignore it.
-    //
-    // This behavior applies to `jj git remote remove` and
-    // `jj git remote set-url` as well. It would be hard to change due
-    // to gitoxide’s model, but hopefully it’s relatively harmless.
-    insta::assert_snapshot!(output, @"");
-    insta::assert_snapshot!(read_git_config(work_dir.root()), @r#"
-    [core]
-    	repositoryformatversion = 0
-    	bare = true
-    	logallrefupdates = false
-    [remote "bar"]
-    	url = htps://example.com/repo/foo
-    	fetch = +refs/heads/*:refs/remotes/bar/*
-    "#);
-    // This has the unfortunate consequence that the original remote
-    // still exists after renaming.
-    let output = work_dir.run_jj(["git", "remote", "list"]);
     insta::assert_snapshot!(output, @r"
-    bar htps://example.com/repo/foo
-    foo htps://example.com/repo/foo
+    ------- stderr -------
+    Error: No git remote named 'foo'
     [EOF]
+    [exit status: 1]
     ");
 
     let output = work_dir.run_jj([
@@ -610,7 +592,6 @@ fn test_git_remote_with_global_git_remote_config() {
 
     let output = work_dir.run_jj(["git", "remote", "list"]);
     insta::assert_snapshot!(output, @r"
-    bar htps://example.com/repo/foo
     foo htps://example.com/repo/foo
     origin https://example.com/repo/origin/2
     [EOF]
@@ -620,9 +601,6 @@ fn test_git_remote_with_global_git_remote_config() {
     	repositoryformatversion = 0
     	bare = true
     	logallrefupdates = false
-    [remote "bar"]
-    	url = htps://example.com/repo/foo
-    	fetch = +refs/heads/*:refs/remotes/bar/*
     [remote "origin"]
     	url = https://example.com/repo/origin/2
     	fetch = +refs/heads/*:refs/remotes/origin/*

lib/src/git.rs

@@ -1922,6 +1922,19 @@ fn remove_remote_git_config_sections(
     Ok(())
 }
 
+/// Checks if non-empty configuration for a remote exists in the local
+/// .git/config file
+fn remote_exists_in_local_config(git_repo: &gix::Repository, remote_name: &RemoteName) -> bool {
+    let config = git_repo.config_snapshot();
+    let subsection_name = Some(BStr::new(remote_name.as_str()));
+    match config.section("remote", subsection_name) {
+        Ok(section) => {
+            section.num_values() > 0 && section.meta().source == gix::config::Source::Local
+        }
+        Err(_) => false,
+    }
+}
+
 /// Returns a sorted list of configured remote names.
 pub fn get_all_remote_names(
     store: &Store,
@@ -1952,7 +1965,7 @@ pub fn add_remote(
 
     validate_remote_name(remote_name)?;
 
-    if git_repo.try_find_remote(remote_name.as_str()).is_some() {
+    if remote_exists_in_local_config(&git_repo, remote_name) {
         return Err(GitRemoteManagementError::RemoteAlreadyExists(
             remote_name.to_owned(),
         ));
@@ -2046,14 +2059,20 @@ pub fn rename_remote(
 
     validate_remote_name(new_remote_name)?;
 
+    if !remote_exists_in_local_config(&git_repo, old_remote_name) {
+        return Err(GitRemoteManagementError::NoSuchRemote(
+            old_remote_name.to_owned(),
+        ));
+    }
+
     let Some(result) = git_repo.try_find_remote(old_remote_name.as_str()) else {
         return Err(GitRemoteManagementError::NoSuchRemote(
             old_remote_name.to_owned(),
         ));
     };
     let mut remote = result.map_err(GitRemoteManagementError::from_git)?;
 
-    if git_repo.try_find_remote(new_remote_name.as_str()).is_some() {
+    if remote_exists_in_local_config(&git_repo, new_remote_name) {
         return Err(GitRemoteManagementError::RemoteAlreadyExists(
             new_remote_name.to_owned(),
         ));

lib/tests/test_git.rs

@@ -48,6 +48,7 @@ use jj_lib::git::GitPushError;
 use jj_lib::git::GitPushStats;
 use jj_lib::git::GitRefKind;
 use jj_lib::git::GitRefUpdate;
+use jj_lib::git::GitRemoteManagementError;
 use jj_lib::git::GitResetHeadError;
 use jj_lib::git::GitSettings;
 use jj_lib::git::IgnoredRefspec;
@@ -5028,3 +5029,80 @@ fn auto_track_all() -> HashMap<RemoteNameBuf, RemoteSettings> {
         .map(|name| (name.into(), settings.clone()))
         .collect()
 }
+
+#[test]
+fn test_add_remote_rejects_duplicate_in_local_config() {
+    let test_repo = TestRepo::init_with_backend(TestRepoBackend::Git);
+
+    let mut tx = test_repo.repo.start_transaction();
+    git::add_remote(
+        tx.repo_mut(),
+        "foo".as_ref(),
+        "https://example.com/",
+        Default::default(),
+        None,
+    )
+    .unwrap();
+    let _repo = tx.commit("test").unwrap();
+    // Reload after Git configuration change.
+    let repo = &test_repo
+        .env
+        .load_repo_at_head(&testutils::user_settings(), test_repo.repo_path());
+
+    let mut tx = repo.start_transaction();
+    let result = git::add_remote(
+        tx.repo_mut(),
+        "foo".as_ref(),
+        "https://example.com/other",
+        Default::default(),
+        None,
+    );
+
+    assert_matches!(
+        result,
+        Err(GitRemoteManagementError::RemoteAlreadyExists(name)) if name.as_str() == "foo"
+    );
+}
+
+#[test]
+fn test_rename_remote_rejects_when_new_exists_in_local_config() {
+    let test_repo = TestRepo::init_with_backend(TestRepoBackend::Git);
+
+    let mut tx = test_repo.repo.start_transaction();
+    git::add_remote(
+        tx.repo_mut(),
+        "foo".as_ref(),
+        "https://example.com/foo",
+        Default::default(),
+        None,
+    )
+    .unwrap();
+    let _repo = tx.commit("test").unwrap();
+    // Reload after Git configuration change.
+    let repo = &test_repo
+        .env
+        .load_repo_at_head(&testutils::user_settings(), test_repo.repo_path());
+
+    let mut tx = repo.start_transaction();
+    git::add_remote(
+        tx.repo_mut(),
+        "bar".as_ref(),
+        "https://example.com/bar",
+        Default::default(),
+        None,
+    )
+    .unwrap();
+    let _repo = tx.commit("test").unwrap();
+    // Reload after Git configuration change.
+    let repo = &test_repo
+        .env
+        .load_repo_at_head(&testutils::user_settings(), test_repo.repo_path());
+
+    let mut tx = repo.start_transaction();
+    let result = git::rename_remote(tx.repo_mut(), "foo".as_ref(), "bar".as_ref());
+
+    assert_matches!(
+        result,
+        Err(GitRemoteManagementError::RemoteAlreadyExists(name)) if name.as_str() == "bar"
+    );
+}