diff --git a/extensions/ql-vscode/test/unit-tests/common/errors.test.ts b/extensions/ql-vscode/test/unit-tests/common/errors.test.ts
index a7477ce41..ca9e01de3 100644
--- a/extensions/ql-vscode/test/unit-tests/common/errors.test.ts
+++ b/extensions/ql-vscode/test/unit-tests/common/errors.test.ts
@@ -19,6 +19,40 @@ describe("errorMessage", () => {
     ).toEqual("Failed to create database foo");
   });
 
+  it("fullMessageWithStack includes the stack", () => {
+    expect(
+      redactableError`Failed to create database ${"foo"}`.fullMessageWithStack,
+    ).toMatch(
+      /^Failed to create database foo\nError: Failed to create database foo\n +at redactableError \(/,
+    );
+  });
+
+  it("fullMessageWithStack includes the cause stack for given error", () => {
+    function myRealFunction() {
+      throw new Error("Internal error");
+    }
+
+    let error: Error;
+    try {
+      myRealFunction();
+
+      fail("Expected an error to be thrown");
+    } catch (e: unknown) {
+      if (!(e instanceof Error)) {
+        throw new Error("Expected an Error to be thrown");
+      }
+
+      error = e;
+    }
+
+    expect(
+      redactableError(error)`Failed to create database ${"foo"}`
+        .fullMessageWithStack,
+    ).toMatch(
+      /^Failed to create database foo\nError: Internal error\n +at myRealFunction \(/,
+    );
+  });
+
   it("redactedMessage redacts the given message", () => {
     expect(
       redactableError`Failed to create database ${"foo"}`.redactedMessage,