fix(tabs): allow saving a saved sql tab after clearing content

Closes #9247

apps/desktop/src/lib/__tests__/tabs/sqlTabSaveTarget.spec.ts

@@ -0,0 +1,41 @@
+import { describe, expect, it } from "vitest";
+import { canSaveSqlTab, type SqlTabSaveTarget } from "@/lib/tabs/sqlTabSaveTarget";
+
+const PROCEDURE_SOURCE = { schema: "dbo", name: "p", objectType: "PROCEDURE" } as const;
+
+function saveTarget(overrides: Partial<SqlTabSaveTarget>): SqlTabSaveTarget {
+  return { externalSqlPath: undefined, savedSqlId: undefined, sql: "", objectSource: undefined, ...overrides };
+}
+
+describe("canSaveSqlTab", () => {
+  it("keeps a saved SQL library tab saveable after its content is deleted", () => {
+    // Issue #9247: emptying a query file is a legitimate edit that must reach the file.
+    expect(canSaveSqlTab(saveTarget({ savedSqlId: "file-1", sql: "" }))).toBe(true);
+  });
+
+  it("treats whitespace-only content in a saved tab as the emptied state, not as content", () => {
+    expect(canSaveSqlTab(saveTarget({ savedSqlId: "file-1", sql: "\n\t " }))).toBe(true);
+  });
+
+  it("keeps an external .sql file tab saveable after its content is deleted", () => {
+    expect(canSaveSqlTab(saveTarget({ externalSqlPath: "/tmp/query.sql", sql: "" }))).toBe(true);
+  });
+
+  it("still allows a brand-new tab with content", () => {
+    expect(canSaveSqlTab(saveTarget({ sql: "SELECT 1;" }))).toBe(true);
+  });
+
+  it("still blocks a brand-new tab with nothing to persist", () => {
+    expect(canSaveSqlTab(saveTarget({ sql: "  \n" }))).toBe(false);
+  });
+
+  it("still blocks an emptied object-source tab", () => {
+    // Saving an empty routine body would send a body-less CREATE to the server.
+    expect(canSaveSqlTab(saveTarget({ objectSource: PROCEDURE_SOURCE, sql: "" }))).toBe(false);
+    expect(canSaveSqlTab(saveTarget({ objectSource: PROCEDURE_SOURCE, savedSqlId: "file-1", sql: "" }))).toBe(false);
+  });
+
+  it("allows an object-source tab with content", () => {
+    expect(canSaveSqlTab(saveTarget({ objectSource: PROCEDURE_SOURCE, sql: "CREATE PROCEDURE dbo.p AS SELECT 1;" }))).toBe(true);
+  });
+});

apps/desktop/src/lib/tabs/sqlTabSaveTarget.ts

@@ -0,0 +1,22 @@
+import type { QueryTab } from "@/types/database";
+
+/** Tab fields that decide whether its SQL can be persisted. */
+export type SqlTabSaveTarget = Pick<QueryTab, "externalSqlPath" | "savedSqlId" | "sql" | "objectSource">;
+
+/**
+ * Whether the tab's SQL can be saved at all.
+ *
+ * A tab that already has a persistence target — an external `.sql` file or a
+ * saved-SQL library entry — stays saveable after its content is emptied.
+ * Deleting everything is a legitimate edit that must reach the target, and the
+ * emptied state is also the only state in which the user can observe the guard.
+ *
+ * A brand-new tab has nothing to persist, and an emptied object-source tab would
+ * push a body-less `CREATE` for a routine or view to the server, so both keep the
+ * content requirement.
+ */
+export function canSaveSqlTab(tab: SqlTabSaveTarget): boolean {
+  if (tab.externalSqlPath || tab.sql.trim()) return true;
+  if (tab.objectSource) return false;
+  return !!tab.savedSqlId;
+}