almost

src-tauri/src/git.rs

@@ -82,6 +82,15 @@ pub struct GitCommitComparison {
     pub patch: String,
 }
 
+#[derive(Debug, Clone, PartialEq, Eq, Serialize)]
+pub struct ConflictFile {
+    pub path: String,
+    pub content: String,
+    pub ours: Option<String>,
+    pub theirs: Option<String>,
+    pub base: Option<String>,
+}
+
 #[derive(Debug, Clone, PartialEq, Eq, Serialize)]
 pub struct GitRepositoryFile {
     pub path: String,
@@ -260,8 +269,39 @@ pub fn merge_branch(path: String, branch: String) -> Result<GitStatus, String> {
         return Err("Branch-Name darf nicht leer sein.".to_string());
     }
 
-    run_git(&repo, ["merge", "--no-edit", branch])?;
-    status_for_repo(&repo)
+    let output = Command::new("git")
+        .arg("-C")
+        .arg(&repo)
+        .args(["merge", "--no-edit", branch])
+        .output()
+        .map_err(|err| format!("Git konnte nicht gestartet werden. Ist Git installiert? {err}"))?;
+
+    if output.status.success() {
+        return status_for_repo(&repo);
+    }
+
+    // A merge that stops on conflicts leaves unmerged paths in the work tree.
+    // Surface those through the status so the UI can offer conflict resolution
+    // instead of treating the conflict as a hard error.
+    let status = status_for_repo(&repo)?;
+    if status.files.iter().any(|file| {
+        matches!(file.staged, Some(FileStatusKind::Conflicted))
+            || matches!(file.unstaged, Some(FileStatusKind::Conflicted))
+    }) {
+        return Ok(status);
+    }
+
+    let stderr = String::from_utf8_lossy(&output.stderr);
+    let stdout = String::from_utf8_lossy(&output.stdout);
+    let details = if !stderr.trim().is_empty() {
+        stderr.trim()
+    } else if !stdout.trim().is_empty() {
+        stdout.trim()
+    } else {
+        "unbekannter Fehler"
+    };
+
+    Err(format!("Merge fehlgeschlagen: {details}"))
 }
 
 #[tauri::command]
@@ -435,6 +475,56 @@ pub fn diff_file_against_working_tree(
     })
 }
 
+#[tauri::command]
+pub fn read_conflict(path: String, file: String) -> Result<ConflictFile, String> {
+    let repo = resolve_repo(&path)?;
+    validate_files(std::slice::from_ref(&file))?;
+
+    let content = std::fs::read_to_string(repo.join(&file))
+        .map_err(|err| format!("Konfliktdatei konnte nicht gelesen werden: {err}"))?;
+
+    Ok(ConflictFile {
+        base: read_index_stage(&repo, 1, &file),
+        ours: read_index_stage(&repo, 2, &file),
+        theirs: read_index_stage(&repo, 3, &file),
+        path: file,
+        content,
+    })
+}
+
+#[tauri::command]
+pub fn resolve_conflict(path: String, file: String, content: String) -> Result<GitStatus, String> {
+    let repo = resolve_repo(&path)?;
+    validate_files(std::slice::from_ref(&file))?;
+
+    let target = repo.join(&file);
+    if let Some(parent) = target.parent() {
+        std::fs::create_dir_all(parent)
+            .map_err(|err| format!("Verzeichnis konnte nicht erstellt werden: {err}"))?;
+    }
+    std::fs::write(&target, content)
+        .map_err(|err| format!("Konfliktdatei konnte nicht geschrieben werden: {err}"))?;
+
+    run_git_with_paths(&repo, &["add"], std::slice::from_ref(&file))?;
+    status_for_repo(&repo)
+}
+
+fn read_index_stage(repo: &Path, stage: u8, file: &str) -> Option<String> {
+    let spec = format!(":{stage}:{file}");
+    let output = Command::new("git")
+        .arg("-C")
+        .arg(repo)
+        .args(["show", spec.as_str()])
+        .output()
+        .ok()?;
+
+    if output.status.success() {
+        Some(String::from_utf8_lossy(&output.stdout).to_string())
+    } else {
+        None
+    }
+}
+
 fn short_hash(hash: &str) -> String {
     hash.chars().take(7).collect()
 }
@@ -1505,6 +1595,57 @@ mod tests {
         assert!(comparison.patch.contains("working tree change"));
     }
 
+    #[test]
+    fn read_and_resolve_conflict_round_trip() {
+        let repo = init_temp_repo("resolve_conflict");
+        fs::write(repo.path.join("file.txt"), "base\n").expect("base file should be written");
+        run_git_test(&repo.path, ["add", "file.txt"]);
+        run_git_test(&repo.path, ["commit", "-q", "-m", "base"]);
+        let main_branch = git_output_test(&repo.path, ["rev-parse", "--abbrev-ref", "HEAD"]);
+
+        run_git_test(&repo.path, ["checkout", "-q", "-b", "feature"]);
+        fs::write(repo.path.join("file.txt"), "theirs change\n").expect("feature change");
+        run_git_test(&repo.path, ["commit", "-q", "-am", "feature change"]);
+
+        run_git_test(&repo.path, ["checkout", "-q", main_branch.as_str()]);
+        fs::write(repo.path.join("file.txt"), "ours change\n").expect("main change");
+        run_git_test(&repo.path, ["commit", "-q", "-am", "main change"]);
+
+        // The merge is expected to fail with a conflict, so run git directly.
+        let _ = Command::new("git")
+            .arg("-C")
+            .arg(&repo.path)
+            .args(["merge", "--no-edit", "feature"])
+            .output()
+            .expect("git merge should start");
+
+        let conflict =
+            read_conflict(repo.path.to_string_lossy().to_string(), "file.txt".to_string()).unwrap();
+        assert_eq!(
+            conflict.ours.unwrap().replace("\r\n", "\n"),
+            "ours change\n"
+        );
+        assert_eq!(
+            conflict.theirs.unwrap().replace("\r\n", "\n"),
+            "theirs change\n"
+        );
+        assert!(conflict.content.contains("<<<<<<<"));
+
+        let status = resolve_conflict(
+            repo.path.to_string_lossy().to_string(),
+            "file.txt".to_string(),
+            "resolved\n".to_string(),
+        )
+        .unwrap();
+
+        assert!(!status.files.iter().any(|file| {
+            matches!(file.staged, Some(FileStatusKind::Conflicted))
+                || matches!(file.unstaged, Some(FileStatusKind::Conflicted))
+        }));
+        let contents = fs::read_to_string(repo.path.join("file.txt")).unwrap();
+        assert_eq!(contents.replace("\r\n", "\n"), "resolved\n");
+    }
+
     #[test]
     fn restore_staged_added_file_removes_it_from_index_and_worktree() {
         let repo = init_temp_repo("restore_staged_added_file");