refactor(desktop): derive v2 base branch from git config

apps/desktop/src/renderer/hooks/host-service/useGitStatus/useGitStatus.ts

@@ -1,6 +1,5 @@
 import { workspaceTrpc } from "@superset/workspace-client";
 import { useCallback } from "react";
-import { useCollections } from "renderer/routes/_authenticated/providers/CollectionsProvider";
 import { useWorkspaceEvent } from "../useWorkspaceEvent";
 
 /**
@@ -15,20 +14,25 @@ import { useWorkspaceEvent } from "../useWorkspaceEvent";
  * debounce needed.
  */
 export function useGitStatus(workspaceId: string) {
-	const collections = useCollections();
-	const baseBranch: string | null =
-		collections.v2WorkspaceLocalState.get(workspaceId)?.sidebarState
-			?.baseBranch ?? null;
-
 	const utils = workspaceTrpc.useUtils();
 
+	const baseBranchQuery = workspaceTrpc.git.getBaseBranch.useQuery(
+		{ workspaceId },
+		{ staleTime: Number.POSITIVE_INFINITY, enabled: Boolean(workspaceId) },
+	);
+	const baseBranch = baseBranchQuery.data?.baseBranch ?? null;
+
 	const query = workspaceTrpc.git.getStatus.useQuery(
 		{ workspaceId, baseBranch: baseBranch ?? undefined },
 		{ refetchOnWindowFocus: true, enabled: Boolean(workspaceId) },
 	);
 
 	const invalidate = useCallback(() => {
 		void utils.git.getStatus.invalidate({ workspaceId });
+		// Current branch may have changed (external checkout), and
+		// branch.<name>.base is per-branch — drop the cache so the next read
+		// picks up the new branch's base.
+		void utils.git.getBaseBranch.invalidate({ workspaceId });
 	}, [utils, workspaceId]);
 
 	useWorkspaceEvent("git:changed", workspaceId, invalidate);

apps/desktop/src/renderer/routes/_authenticated/_dashboard/v2-workspace/$workspaceId/components/WorkspaceSidebar/hooks/useChangesTab/components/ChangesHeader/ChangesHeader.tsx

@@ -8,6 +8,7 @@ import { CommitFilterDropdown } from "../CommitFilterDropdown";
 interface ChangesHeaderProps {
 	currentBranch: { name: string; aheadCount: number; behindCount: number };
 	defaultBranchName: string;
+	baseBranch: string | null;
 	commitCount: number;
 	totalFiles: number;
 	totalAdditions: number;
@@ -25,6 +26,7 @@ interface ChangesHeaderProps {
 export function ChangesHeader({
 	currentBranch,
 	defaultBranchName,
+	baseBranch,
 	commitCount,
 	totalFiles,
 	totalAdditions,
@@ -103,7 +105,7 @@ export function ChangesHeader({
 				{commitCount} {commitCount === 1 ? "commit" : "commits"} from{" "}
 				<BaseBranchSelector
 					branches={branches}
-					currentValue={defaultBranchName}
+					currentValue={baseBranch ?? defaultBranchName}
 					onChange={onBaseBranchChange}
 				/>
 			</div>

apps/desktop/src/renderer/routes/_authenticated/_dashboard/v2-workspace/$workspaceId/components/WorkspaceSidebar/hooks/useChangesTab/components/ChangesTabContent/ChangesTabContent.tsx

@@ -16,6 +16,7 @@ interface ChangesTabContentProps {
 	commits: { data: RouterOutputs["git"]["listCommits"] | undefined };
 	branches: { data: RouterOutputs["git"]["listBranches"] | undefined };
 	filter: ChangesFilter;
+	baseBranch: string | null;
 	files: ChangesetFile[];
 	isLoading: boolean;
 	totalChanges: number;
@@ -35,6 +36,7 @@ export const ChangesTabContent = memo(function ChangesTabContent({
 	commits,
 	branches,
 	filter,
+	baseBranch,
 	files,
 	isLoading,
 	totalChanges,
@@ -69,6 +71,7 @@ export const ChangesTabContent = memo(function ChangesTabContent({
 			<ChangesHeader
 				currentBranch={status.data.currentBranch}
 				defaultBranchName={status.data.defaultBranch.name}
+				baseBranch={baseBranch}
 				commitCount={commits.data?.commits.length ?? 0}
 				totalFiles={totalChanges}
 				totalAdditions={totalAdditions}

apps/desktop/src/renderer/routes/_authenticated/_dashboard/v2-workspace/$workspaceId/components/WorkspaceSidebar/hooks/useChangesTab/useChangesTab.tsx

@@ -24,12 +24,17 @@ export function useChangesTab({
 	onSelectFile,
 }: UseChangesTabParams): SidebarTabDefinition {
 	const collections = useCollections();
+	const utils = workspaceTrpc.useUtils();
 	const localState = collections.v2WorkspaceLocalState.get(workspaceId);
 	const filter: ChangesFilter = localState?.sidebarState?.changesFilter ?? {
 		kind: "all",
 	};
-	const baseBranch: string | null =
-		localState?.sidebarState?.baseBranch ?? null;
+
+	const baseBranchQuery = workspaceTrpc.git.getBaseBranch.useQuery(
+		{ workspaceId },
+		{ staleTime: Number.POSITIVE_INFINITY },
+	);
+	const baseBranch = baseBranchQuery.data?.baseBranch ?? null;
 
 	const { viewedSet, setViewed } = useViewedFiles(workspaceId);
 
@@ -46,14 +51,20 @@ export function useChangesTab({
 		[collections, workspaceId],
 	);
 
+	const setBaseBranchMutation = workspaceTrpc.git.setBaseBranch.useMutation({
+		onSuccess: () => {
+			void utils.git.getBaseBranch.invalidate({ workspaceId });
+			void utils.git.getStatus.invalidate({ workspaceId });
+			void utils.git.listCommits.invalidate({ workspaceId });
+			void utils.git.getDiff.invalidate({ workspaceId });
+		},
+	});
+
 	const setBaseBranch = useCallback(
 		(branchName: string) => {
-			if (!collections.v2WorkspaceLocalState.get(workspaceId)) return;
-			collections.v2WorkspaceLocalState.update(workspaceId, (draft) => {
-				draft.sidebarState.baseBranch = branchName;
-			});
+			setBaseBranchMutation.mutate({ workspaceId, baseBranch: branchName });
 		},
-		[collections, workspaceId],
+		[setBaseBranchMutation, workspaceId],
 	);
 
 	const commits = workspaceTrpc.git.listCommits.useQuery(
@@ -101,6 +112,7 @@ export function useChangesTab({
 			commits={commits}
 			branches={branches}
 			filter={filter}
+			baseBranch={baseBranch}
 			files={files}
 			isLoading={isLoading}
 			totalChanges={totalChanges}

apps/desktop/src/renderer/routes/_authenticated/_dashboard/v2-workspace/$workspaceId/hooks/useSidebarDiffRef/useSidebarDiffRef.ts

@@ -1,3 +1,4 @@
+import { workspaceTrpc } from "@superset/workspace-client";
 import { eq } from "@tanstack/db";
 import { useLiveQuery } from "@tanstack/react-db";
 import { useMemo } from "react";
@@ -15,7 +16,12 @@ export function useSidebarDiffRef(workspaceId: string): DiffRef {
 	);
 	const sidebarState = rows[0]?.sidebarState;
 	const filter = sidebarState?.changesFilter ?? { kind: "all" };
-	const baseBranch = sidebarState?.baseBranch ?? null;
+
+	const baseBranchQuery = workspaceTrpc.git.getBaseBranch.useQuery(
+		{ workspaceId },
+		{ staleTime: Number.POSITIVE_INFINITY },
+	);
+	const baseBranch = baseBranchQuery.data?.baseBranch ?? null;
 
 	const filterKind = filter.kind;
 	const commitHash =

apps/desktop/src/renderer/routes/_authenticated/providers/CollectionsProvider/dashboardSidebarLocal/schema.ts

@@ -36,7 +36,6 @@ export const workspaceLocalStateSchema = z.object({
 		tabOrder: z.number().int().default(0),
 		sectionId: z.string().uuid().nullable().default(null),
 		changesFilter: changesFilterSchema.default({ kind: "all" }),
-		baseBranch: z.string().nullable().default(null),
 	}),
 	paneLayout: paneWorkspaceStateSchema,
 	rightSidebarOpen: z.boolean().default(false),

packages/host-service/src/trpc/router/git/git.ts

@@ -231,6 +231,58 @@ export const gitRouter = router({
 			return { files };
 		}),
 
+	getBaseBranch: protectedProcedure
+		.input(z.object({ workspaceId: z.string() }))
+		.query(async ({ ctx, input }) => {
+			const worktreePath = resolveWorktreePath(ctx, input.workspaceId);
+			const git = await ctx.git(worktreePath);
+			const currentBranch = (
+				await git.revparse(["--abbrev-ref", "HEAD"]).catch(() => "")
+			).trim();
+			if (!currentBranch || currentBranch === "HEAD") {
+				return { baseBranch: null as string | null };
+			}
+			const configured = (
+				await git
+					.raw(["config", `branch.${currentBranch}.base`])
+					.catch(() => "")
+			).trim();
+			return { baseBranch: (configured || null) as string | null };
+		}),
+
+	setBaseBranch: protectedProcedure
+		.input(
+			z.object({
+				workspaceId: z.string(),
+				baseBranch: z.string().nullable(),
+			}),
+		)
+		.mutation(async ({ ctx, input }) => {
+			const worktreePath = resolveWorktreePath(ctx, input.workspaceId);
+			const git = await ctx.git(worktreePath);
+			const currentBranch = (
+				await git.revparse(["--abbrev-ref", "HEAD"]).catch(() => "")
+			).trim();
+			if (!currentBranch || currentBranch === "HEAD") {
+				throw new TRPCError({
+					code: "PRECONDITION_FAILED",
+					message: "Cannot set base branch on detached HEAD",
+				});
+			}
+			if (input.baseBranch) {
+				await git.raw([
+					"config",
+					`branch.${currentBranch}.base`,
+					input.baseBranch,
+				]);
+			} else {
+				await git
+					.raw(["config", "--unset", `branch.${currentBranch}.base`])
+					.catch(() => {});
+			}
+			return { baseBranch: input.baseBranch };
+		}),
+
 	renameBranch: protectedProcedure
 		.input(
 			z.object({

packages/host-service/src/trpc/router/workspace-creation/workspace-creation.ts

@@ -639,8 +639,9 @@ export const workspaceCreationRouter = router({
 			// Always create a new branch — never check out an existing one.
 			// Checking out existing branches is a separate intent (createFromPr,
 			// or the picker's Check out action via the `checkout` procedure).
-			// --no-track prevents the new branch from tracking the remote ref
-			// (e.g. origin/main); push.autoSetupRemote handles first-push tracking.
+			// --no-track keeps `git pull` / ahead-behind counts from treating
+			// the start point as the branch's home. Push targeting is handled
+			// separately by push.autoSetupRemote (set below).
 			const startPointArg =
 				startPoint.kind === "head" ? "HEAD" : startPoint.shortName;
 			await git.raw([
@@ -655,6 +656,45 @@ export const workspaceCreationRouter = router({
 					: startPointArg,
 			]);
 
+			// Enable autoSetupRemote so the first terminal `git push` creates
+			// origin/<branchName> and sets it as upstream without requiring
+			// `-u`. Note: `--local` in a linked worktree writes to the shared
+			// repo config, so this applies repo-wide — intentional, every
+			// workspace worktree wants the same ergonomics. Safe against
+			// wrong-upstream targeting because --no-track above guarantees no
+			// upstream exists at first push, so auto-create always wins and
+			// always uses the branch's own name (never the base branch).
+			await git
+				.raw([
+					"-C",
+					worktreePath,
+					"config",
+					"--local",
+					"push.autoSetupRemote",
+					"true",
+				])
+				.catch((err) => {
+					console.warn(
+						"[workspaceCreation.create] failed to set push.autoSetupRemote:",
+						err,
+					);
+				});
+
+			// Record the base branch in git config so the Changes tab knows what
+			// to compare against on first open. startPoint.shortName is the ref
+			// we actually forked from (user selection, resolved against local /
+			// remote). Skipped for "head" start point — no meaningful base.
+			if (startPoint.kind !== "head") {
+				await git
+					.raw(["config", `branch.${branchName}.base`, startPoint.shortName])
+					.catch((err) => {
+						console.warn(
+							`[workspaceCreation.create] failed to record base branch ${startPoint.shortName}:`,
+							err,
+						);
+					});
+			}
+
 			setProgress(input.pendingId, "registering");
 
 			// 4. Register cloud workspace row
@@ -909,6 +949,28 @@ export const workspaceCreationRouter = router({
 				throw new TRPCError({ code: "CONFLICT", message });
 			}
 
+			// Enable autoSetupRemote so the first terminal `git push` on a
+			// local-only branch creates origin/<branch> without requiring -u.
+			// Branches checked out from a remote already have upstream set
+			// via --track above, so this config is a no-op for them.
+			// `--local` in a linked worktree writes to the shared repo config,
+			// so this applies repo-wide — intentional.
+			await git
+				.raw([
+					"-C",
+					worktreePath,
+					"config",
+					"--local",
+					"push.autoSetupRemote",
+					"true",
+				])
+				.catch((err) => {
+					console.warn(
+						"[workspaceCreation.checkout] failed to set push.autoSetupRemote:",
+						err,
+					);
+				});
+
 			setProgress(input.pendingId, "registering");
 
 			const rollbackWorktree = async () => {