test: add tests for undefined and file stream

Author: trivikr

packages/util-body-length-node/src/calculateBodyLength.spec.ts

@@ -1,12 +1,23 @@
+import { lstatSync } from "fs";
+
 import { calculateBodyLength } from "./calculateBodyLength";
 
-const arrayBuffer = new ArrayBuffer(1);
-const typedArray = new Uint8Array(1);
-const view = new DataView(arrayBuffer);
+jest.mock("fs");
 
 describe(calculateBodyLength.name, () => {
-  it("should handle null/undefined objects", () => {
-    expect(calculateBodyLength(null)).toEqual(0);
+  const arrayBuffer = new ArrayBuffer(1);
+  const typedArray = new Uint8Array(1);
+  const view = new DataView(arrayBuffer);
+
+  afterEach(() => {
+    jest.clearAllMocks();
+  });
+
+  it.each([
+    [0, null],
+    [0, undefined],
+  ])("should return %s for %s", (output, input) => {
+    expect(calculateBodyLength(input)).toEqual(output);
   });
 
   it("should handle string inputs", () => {
@@ -28,4 +39,13 @@ describe(calculateBodyLength.name, () => {
   it("should handle DataView inputs", () => {
     expect(calculateBodyLength(view)).toEqual(1);
   });
+
+  it("should handle stream created using fs.createReadStream", () => {
+    const mockSize = { size: 10 };
+    (lstatSync as jest.Mock).mockReturnValue(mockSize);
+
+    // Populate path as string to mock body created from fs.createReadStream
+    const mockBody = { path: "mockPath" };
+    expect(calculateBodyLength(mockBody)).toEqual(mockSize.size);
+  });
 });