Add parseRangeHeader tests.

src/parseRangeHeader.spec.ts

@@ -0,0 +1,58 @@
+import { parseRangeHeader } from "./parseRangeHeader";
+import { SinonSandbox, createSandbox } from "sinon";
+import { Logger } from "./Logger";
+import { expect } from "chai";
+import { RangeParserError } from "./RangeParserError";
+
+describe("parseRangeHeader tests", () => {
+  let sandbox: SinonSandbox;
+  let logger: Logger;
+  beforeEach(() => {
+    sandbox = createSandbox();
+    logger = {
+      debug: sandbox.stub() as (message: string, extra?: any) => void
+    };
+  });
+  afterEach(() => {
+    sandbox.restore();
+  });
+  it("returns null if range is not specified", () => {
+    let value = parseRangeHeader("", 10, logger);
+    expect(value).to.be.equal(null);
+    value = parseRangeHeader(null, 10, logger);
+    expect(value).to.be.equal(null);
+  });
+  it("returns null if total size is zero", () => {
+    let value = parseRangeHeader("bytes=0-5", 0, logger);
+    expect(value).to.be.equal(null);
+  });
+  it("if end is not provided, sets end to the last byte (totalSize - 1).", () => {
+    let value = parseRangeHeader("bytes=0-", 10, logger);
+    expect(value).to.be.deep.equal({ start: 0, end: 9 });
+  });
+  it('if start is not provided, set it to the offset of last "end" bytes from the end of the file.', () => {
+    let value = parseRangeHeader("bytes=-5", 10, logger);
+    expect(value).to.be.deep.equal({ start: 5, end: 9 });
+  });
+  it("handles invalid ranges", () => {
+    try {
+      parseRangeHeader("bytes=6-5", 10, logger);
+    } catch (error) {
+      expect(error).that.be.instanceOf(RangeParserError);
+    }
+    try {
+      parseRangeHeader("bytes=6-7", 10, logger);
+    } catch (error) {
+      expect(error).that.be.instanceOf(RangeParserError);
+    }
+    try {
+      parseRangeHeader("bytes=6-11", 10, logger);
+    } catch (error) {
+      expect(error).that.be.instanceOf(RangeParserError);
+    }
+  });
+  it("returns a valid parsed range.", () => {
+    let value = parseRangeHeader("bytes=0-5", 10, logger);
+    expect(value).to.be.deep.equal({ start: 0, end: 5 });
+  });
+});