Protect referenced feeder structures from deletion

tests/circuit-device-row-move-project-command.repository.test.ts

@@ -14,6 +14,7 @@ import { circuitDeviceRows } from "../src/db/schema/circuit-device-rows.js";
 import { circuitProtectionDevices } from "../src/db/schema/circuit-protection-devices.js";
 import { circuitSections } from "../src/db/schema/circuit-sections.js";
 import { circuits } from "../src/db/schema/circuits.js";
+import { distributionBoards } from "../src/db/schema/distribution-boards.js";
 import { projectRevisions } from "../src/db/schema/project-revisions.js";
 import { projects } from "../src/db/schema/projects.js";
 import {
@@ -611,6 +612,62 @@ describe("circuit device-row move project-command repository", () => {
     }
   });
 
+  it("blocks undo from removing a generated circuit used as a feeder", () => {
+    const fixture = createTestDatabase();
+    try {
+      const store = new CircuitDeviceRowMoveProjectCommandRepository(
+        fixture.context.db
+      );
+      const targetCircuit = createMoveTargetSnapshot(fixture);
+      const command = createCircuitDeviceRowMoveWithNewCircuitProjectCommand(
+        "create",
+        targetCircuit,
+        [{
+          rowId: "row-1",
+          expectedCircuitId: "circuit-1",
+          expectedSortOrder: 10,
+          targetCircuitId: targetCircuit.id,
+          targetSortOrder: 10,
+        }]
+      );
+      const moved = store.execute({
+        projectId: "project-1",
+        expectedRevision: 0,
+        source: "user",
+        command,
+      });
+      const downstream = new DistributionBoardFixtureRepository(
+        fixture.context.db
+      ).createWithCircuitListAndDefaultSections("project-1", "UV-02");
+      fixture.context.db
+        .update(distributionBoards)
+        .set({
+          feedingDistributionBoardId: fixture.circuitListId,
+          feedingCircuitId: targetCircuit.id,
+        })
+        .where(eq(distributionBoards.id, downstream.id))
+        .run();
+
+      assert.throws(
+        () => store.execute({
+          projectId: "project-1",
+          expectedRevision: 1,
+          source: "undo",
+          historyTargetChangeSetId: moved.revision.changeSetId,
+          command: moved.inverse,
+        }),
+        /Speist UV-02 – erst Einspeisung ändern\./
+      );
+      assert.equal(getRow(fixture.context, "row-1")?.circuitId, targetCircuit.id);
+      assert.ok(
+        fixture.context.db.select().from(circuits)
+          .where(eq(circuits.id, targetCircuit.id)).get()
+      );
+    } finally {
+      fixture.context.close();
+    }
+  });
+
   it("rejects deletion when the created target changed outside history", () => {
     const fixture = createTestDatabase();
     try {