Git uncommit warning (#25977)

Adds a prompt when clicking the uncommit button when the current commit
is already present on a remote branch:

![screenshot showing
prompt](https://github.com/user-attachments/assets/d6421875-588e-4db0-aee0-a92f36bce94b)

Release Notes:

- N/A

---------

Co-authored-by: Conrad <conrad@zed.dev>

crates/collab/src/rpc.rs

@@ -407,6 +407,7 @@ impl Server {
             .add_request_handler(forward_mutating_project_request::<proto::OpenCommitMessageBuffer>)
             .add_request_handler(forward_mutating_project_request::<proto::GitCreateBranch>)
             .add_request_handler(forward_mutating_project_request::<proto::GitChangeBranch>)
+            .add_request_handler(forward_mutating_project_request::<proto::CheckForPushedCommits>)
             .add_message_handler(broadcast_project_message_from_host::<proto::AdvertiseContexts>)
             .add_message_handler(update_context)
             .add_request_handler({

crates/git/src/repository.rs

@@ -202,8 +202,12 @@ pub trait GitRepository: Send + Sync {
         options: Option<PushOptions>,
     ) -> Result<RemoteCommandOutput>;
     fn pull(&self, branch_name: &str, upstream_name: &str) -> Result<RemoteCommandOutput>;
-    fn get_remotes(&self, branch_name: Option<&str>) -> Result<Vec<Remote>>;
     fn fetch(&self) -> Result<RemoteCommandOutput>;
+
+    fn get_remotes(&self, branch_name: Option<&str>) -> Result<Vec<Remote>>;
+
+    /// returns a list of remote branches that contain HEAD
+    fn check_for_pushed_commit(&self) -> Result<Vec<SharedString>>;
 }
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Deserialize, JsonSchema)]
@@ -781,6 +785,54 @@ impl GitRepository for RealGitRepository {
             ));
         }
     }
+
+    fn check_for_pushed_commit(&self) -> Result<Vec<SharedString>> {
+        let working_directory = self.working_directory()?;
+        let git_cmd = |args: &[&str]| -> Result<String> {
+            let output = new_std_command(&self.git_binary_path)
+                .current_dir(&working_directory)
+                .args(args)
+                .output()?;
+            if output.status.success() {
+                Ok(String::from_utf8(output.stdout)?)
+            } else {
+                Err(anyhow!(String::from_utf8_lossy(&output.stderr).to_string()))
+            }
+        };
+
+        let head = git_cmd(&["rev-parse", "HEAD"])
+            .context("Failed to get HEAD")?
+            .trim()
+            .to_owned();
+
+        let mut remote_branches = vec![];
+        let mut add_if_matching = |remote_head: &str| {
+            if let Ok(merge_base) = git_cmd(&["merge-base", &head, remote_head]) {
+                if merge_base.trim() == head {
+                    if let Some(s) = remote_head.strip_prefix("refs/remotes/") {
+                        remote_branches.push(s.to_owned().into());
+                    }
+                }
+            }
+        };
+
+        // check the main branch of each remote
+        let remotes = git_cmd(&["remote"]).context("Failed to get remotes")?;
+        for remote in remotes.lines() {
+            if let Ok(remote_head) =
+                git_cmd(&["symbolic-ref", &format!("refs/remotes/{remote}/HEAD")])
+            {
+                add_if_matching(remote_head.trim());
+            }
+        }
+
+        // ... and the remote branch that the checked-out one is tracking
+        if let Ok(remote_head) = git_cmd(&["rev-parse", "--symbolic-full-name", "@{u}"]) {
+            add_if_matching(remote_head.trim());
+        }
+
+        Ok(remote_branches)
+    }
 }
 
 #[cfg(not(windows))]
@@ -998,6 +1050,10 @@ impl GitRepository for FakeGitRepository {
     fn get_remotes(&self, _branch: Option<&str>) -> Result<Vec<Remote>> {
         unimplemented!()
     }
+
+    fn check_for_pushed_commit(&self) -> Result<Vec<SharedString>> {
+        unimplemented!()
+    }
 }
 
 fn check_path_to_repo_path_errors(relative_file_path: &Path) -> Result<()> {

crates/git_ui/src/git_panel.rs

@@ -1265,34 +1265,20 @@ impl GitPanel {
             return;
         };
 
-        // TODO: Use git merge-base to find the upstream and main branch split
-        let confirmation = Task::ready(true);
-        // let confirmation = if self.commit_editor.read(cx).is_empty(cx) {
-        //     Task::ready(true)
-        // } else {
-        //     let prompt = window.prompt(
-        //         PromptLevel::Warning,
-        //         "Uncomitting will replace the current commit message with the previous commit's message",
-        //         None,
-        //         &["Ok", "Cancel"],
-        //         cx,
-        //     );
-        //     cx.spawn(|_, _| async move { prompt.await.is_ok_and(|i| i == 0) })
-        // };
-
+        let confirmation = self.check_for_pushed_commits(window, cx);
         let prior_head = self.load_commit_details("HEAD", cx);
 
         let task = cx.spawn_in(window, |this, mut cx| async move {
             let result = maybe!(async {
-                if !confirmation.await {
-                    Ok(None)
-                } else {
+                if let Ok(true) = confirmation.await {
                     let prior_head = prior_head.await?;
 
                     repo.update(&mut cx, |repo, _| repo.reset("HEAD^", ResetMode::Soft))?
                         .await??;
 
                     Ok(Some(prior_head))
+                } else {
+                    Ok(None)
                 }
             })
             .await;
@@ -1315,6 +1301,48 @@ impl GitPanel {
         self.pending_commit = Some(task);
     }
 
+    fn check_for_pushed_commits(
+        &mut self,
+        window: &mut Window,
+        cx: &mut Context<Self>,
+    ) -> impl Future<Output = Result<bool, anyhow::Error>> {
+        let repo = self.active_repository.clone();
+        let mut cx = window.to_async(cx);
+
+        async move {
+            let Some(repo) = repo else {
+                return Err(anyhow::anyhow!("No active repository"));
+            };
+
+            let pushed_to: Vec<SharedString> = repo
+                .update(&mut cx, |repo, _| repo.check_for_pushed_commits())?
+                .await??;
+
+            if pushed_to.is_empty() {
+                Ok(true)
+            } else {
+                #[derive(strum::EnumIter, strum::VariantNames)]
+                #[strum(serialize_all = "title_case")]
+                enum CancelUncommit {
+                    Uncommit,
+                    Cancel,
+                }
+                let detail = format!(
+                    "This commit was already pushed to {}.",
+                    pushed_to.into_iter().join(", ")
+                );
+                let result = cx
+                    .update(|window, cx| prompt("Are you sure?", Some(&detail), window, cx))?
+                    .await?;
+
+                match result {
+                    CancelUncommit::Cancel => Ok(false),
+                    CancelUncommit::Uncommit => Ok(true),
+                }
+            }
+        }
+    }
+
     /// Suggests a commit message based on the changed files and their statuses
     pub fn suggest_commit_message(&self) -> Option<String> {
         if self.total_staged_count() != 1 {

crates/project/src/git.rs

@@ -110,6 +110,7 @@ impl GitStore {
         client.add_entity_request_handler(Self::handle_checkout_files);
         client.add_entity_request_handler(Self::handle_open_commit_message_buffer);
         client.add_entity_request_handler(Self::handle_set_index_text);
+        client.add_entity_request_handler(Self::handle_check_for_pushed_commits);
     }
 
     pub fn active_repository(&self) -> Option<Entity<Repository>> {
@@ -627,6 +628,29 @@ impl GitStore {
         })
     }
 
+    async fn handle_check_for_pushed_commits(
+        this: Entity<Self>,
+        envelope: TypedEnvelope<proto::CheckForPushedCommits>,
+        mut cx: AsyncApp,
+    ) -> Result<proto::CheckForPushedCommitsResponse> {
+        let worktree_id = WorktreeId::from_proto(envelope.payload.worktree_id);
+        let work_directory_id = ProjectEntryId::from_proto(envelope.payload.work_directory_id);
+        let repository_handle =
+            Self::repository_for_request(&this, worktree_id, work_directory_id, &mut cx)?;
+
+        let branches = repository_handle
+            .update(&mut cx, |repository_handle, _| {
+                repository_handle.check_for_pushed_commits()
+            })?
+            .await??;
+        Ok(proto::CheckForPushedCommitsResponse {
+            pushed_to: branches
+                .into_iter()
+                .map(|commit| commit.to_string())
+                .collect(),
+        })
+    }
+
     fn repository_for_request(
         this: &Entity<Self>,
         worktree_id: WorktreeId,
@@ -1423,4 +1447,30 @@ impl Repository {
             }
         })
     }
+
+    pub fn check_for_pushed_commits(&self) -> oneshot::Receiver<Result<Vec<SharedString>>> {
+        self.send_job(|repo| async move {
+            match repo {
+                GitRepo::Local(git_repository) => git_repository.check_for_pushed_commit(),
+                GitRepo::Remote {
+                    project_id,
+                    client,
+                    worktree_id,
+                    work_directory_id,
+                } => {
+                    let response = client
+                        .request(proto::CheckForPushedCommits {
+                            project_id: project_id.0,
+                            worktree_id: worktree_id.to_proto(),
+                            work_directory_id: work_directory_id.to_proto(),
+                        })
+                        .await?;
+
+                    let branches = response.pushed_to.into_iter().map(Into::into).collect();
+
+                    Ok(branches)
+                }
+            }
+        })
+    }
 }

crates/proto/proto/zed.proto

@@ -336,6 +336,9 @@ message Envelope {
         GitGetBranches git_get_branches = 312;
         GitCreateBranch git_create_branch = 313;
         GitChangeBranch git_change_branch = 314; // current max
+
+        CheckForPushedCommits check_for_pushed_commits = 315;
+        CheckForPushedCommitsResponse check_for_pushed_commits_response = 316; // current max
     }
 
     reserved 87 to 88;
@@ -2875,3 +2878,13 @@ message GitChangeBranch {
     uint64 work_directory_id = 3;
     string branch_name = 4;
 }
+
+message CheckForPushedCommits {
+    uint64 project_id = 1;
+    uint64 worktree_id = 2;
+    uint64 work_directory_id = 3;
+}
+
+message CheckForPushedCommitsResponse {
+  repeated string pushed_to = 1;
+}

crates/proto/src/proto.rs

@@ -454,6 +454,8 @@ messages!(
     (RemoteMessageResponse, Background),
     (GitCreateBranch, Background),
     (GitChangeBranch, Background),
+    (CheckForPushedCommits, Background),
+    (CheckForPushedCommitsResponse, Background),
 );
 
 request_messages!(
@@ -598,6 +600,7 @@ request_messages!(
     (Pull, RemoteMessageResponse),
     (GitCreateBranch, Ack),
     (GitChangeBranch, Ack),
+    (CheckForPushedCommits, CheckForPushedCommitsResponse),
 );
 
 entity_messages!(
@@ -701,6 +704,7 @@ entity_messages!(
     Pull,
     GitChangeBranch,
     GitCreateBranch,
+    CheckForPushedCommits,
 );
 
 entity_messages!(