Handle unborn branches in VCS status

.repos/alchemy-effect/packages/alchemy/src/Telemetry/Attributes.ts

@@ -84,7 +84,7 @@ const getGitOriginUrl: Effect.Effect<string | null> = execCapture(
 );
 
 const getBranchName: Effect.Effect<string | null> = execCapture(
-  "git rev-parse --abbrev-ref HEAD",
+  "git symbolic-ref --quiet --short HEAD",
 );
 
 const getRuntime = (): { name: string; version: string } => {

apps/server/src/vcs/GitVcsDriverCore.test.ts

@@ -155,6 +155,26 @@ it.layer(TestLayer)("GitVcsDriver core integration", (it) => {
       }),
     );
 
+    it.effect("reports remote status for an unborn branch", () =>
+      Effect.gen(function* () {
+        const cwd = yield* makeTmpDir();
+        const driver = yield* GitVcsDriver.GitVcsDriver;
+        yield* driver.initRepo({ cwd });
+
+        const status = yield* driver.statusDetailsRemote(cwd);
+
+        assert.equal(status.isRepo, true);
+        assert.equal(
+          status.branch,
+          yield* git(cwd, ["symbolic-ref", "--quiet", "--short", "HEAD"]),
+        );
+        assert.equal(status.hasUpstream, false);
+        assert.equal(status.aheadCount, 0);
+        assert.equal(status.behindCount, 0);
+        assert.equal(status.aheadOfDefaultCount, 0);
+      }),
+    );
+
     it.effect("reports remote divergence without reading working-tree details", () =>
       Effect.gen(function* () {
         const cwd = yield* makeTmpDir();

apps/server/src/vcs/GitVcsDriverCore.ts

@@ -1168,25 +1168,33 @@ export const makeGitVcsDriverCore = Effect.fn("makeGitVcsDriverCore")(function*
     const branchResult = yield* executeGit(
       "GitVcsDriver.statusDetailsRemote.branch",
       cwd,
-      ["rev-parse", "--abbrev-ref", "HEAD"],
+      ["symbolic-ref", "--quiet", "--short", "HEAD"],
       { allowNonZeroExit: true },
     ).pipe(Effect.catchIf(isMissingGitCwdError, () => Effect.succeed(null)));
 
     if (branchResult === null) {
       return NON_REPOSITORY_REMOTE_STATUS_DETAILS;
     }
     if (branchResult.exitCode !== 0) {
-      const stderr = branchResult.stderr.trim();
-      return yield* createGitCommandError(
-        "GitVcsDriver.statusDetailsRemote.branch",
+      const headResult = yield* executeGit(
+        "GitVcsDriver.statusDetailsRemote.head",
         cwd,
-        ["rev-parse", "--abbrev-ref", "HEAD"],
-        stderr || "git branch lookup failed",
+        ["rev-parse", "--verify", "--quiet", "HEAD"],
+        { allowNonZeroExit: true },
       );
+      if (headResult.exitCode !== 0) {
+        const stderr = branchResult.stderr.trim() || headResult.stderr.trim();
+        return yield* createGitCommandError(
+          "GitVcsDriver.statusDetailsRemote.branch",
+          cwd,
+          ["symbolic-ref", "--quiet", "--short", "HEAD"],
+          stderr || "git branch lookup failed",
+        );
+      }
     }
 
     const branchValue = branchResult.stdout.trim();
-    const branch = branchValue.length > 0 && branchValue !== "HEAD" ? branchValue : null;
+    const branch = branchResult.exitCode === 0 && branchValue.length > 0 ? branchValue : null;
     const upstream = yield* resolveCurrentUpstream(cwd);
     const upstreamRef = upstream?.upstreamRef ?? null;
     let aheadCount = 0;