Add tests for custom history implementation

1 files changed, 168 insertions, 0 deletions

diff --git a/gui/test/history.spec.ts b/gui/test/history.spec.ts
new file mode 100644
index 0000000000..1bf00dd4ba
--- /dev/null
+++ b/gui/test/history.spec.ts
@@ -0,0 +1,168 @@
+import { expect, spy } from 'chai';
+import { it, describe, beforeEach } from 'mocha';
+import History from '../src/renderer/lib/history';
+
+const BASE_PATH = '/';
+const FIRST_PATH = '/first-path';
+const SECOND_PATH = '/second-path';
+const THIRD_PATH = '/third-path';
+const FOURTH_PATH = '/fourth-path';
+const FIFTH_PATH = '/fifth-path';
+const SIXTH_PATH = '/sixth-path';
+
+describe('History', () => {
+  let history: History;
+
+  beforeEach(() => {
+    history = new History(BASE_PATH);
+    history.push(FIRST_PATH);
+    history.push(SECOND_PATH);
+    history.push(THIRD_PATH);
+    history.push(FOURTH_PATH);
+  });
+
+  it('should start at the correct location', () => {
+    const history2 = new History(BASE_PATH);
+
+    expect(history2.location.pathname).to.equal(BASE_PATH);
+    expect(history2.length).to.equal(1);
+    expect(history.location.pathname).to.equal(FOURTH_PATH);
+    expect(history.length).to.equal(5);
+  });
+
+  it('should go back', () => {
+    history.goBack();
+    expect(history.location.pathname).to.equal(THIRD_PATH);
+    expect(history.length).to.equal(5);
+  });
+
+  it('should go back three entries', () => {
+    history.go(-3);
+    expect(history.location.pathname).to.equal(FIRST_PATH);
+    expect(history.length).to.equal(5);
+  });
+
+  it('should go forward', () => {
+    history.go(-3);
+    history.goForward();
+    expect(history.location.pathname).to.equal(SECOND_PATH);
+    expect(history.length).to.equal(5);
+  });
+
+  it('should go forward two entries', () => {
+    history.go(-3);
+    history.go(2);
+    expect(history.location.pathname).to.equal(THIRD_PATH);
+    expect(history.length).to.equal(5);
+  });
+
+  it('should fail to go forward', () => {
+    history.goForward();
+    expect(history.location.pathname).to.equal(FOURTH_PATH);
+    expect(history.length).to.equal(5);
+  });
+
+  it('should push', () => {
+    history.push(FIFTH_PATH);
+    history.goBack();
+    expect(history.location.pathname).to.equal(FOURTH_PATH);
+    expect(history.length).to.equal(6);
+  });
+
+  it('should replace', () => {
+    history.replace(FIFTH_PATH);
+    history.goBack();
+    expect(history.location.pathname).to.equal(THIRD_PATH);
+    expect(history.length).to.equal(5);
+  });
+
+  it('should fail to go backwards further than base path', () => {
+    history.go(-5);
+    expect(history.location.pathname).to.equal(FOURTH_PATH);
+    expect(history.length).to.equal(5);
+  });
+
+  it('should go backward to base path', () => {
+    history.reset();
+    expect(history.location.pathname).to.equal(BASE_PATH);
+    expect(history.length).to.equal(5);
+  });
+
+  it('should reset entries with path', () => {
+    history.resetWith(THIRD_PATH);
+    expect(history.location.pathname).to.equal(THIRD_PATH);
+    expect(history.length).to.equal(1);
+
+    history.goBack();
+    expect(history.location.pathname).to.equal(THIRD_PATH);
+    expect(history.length).to.equal(1);
+
+    history.goForward();
+    expect(history.location.pathname).to.equal(THIRD_PATH);
+    expect(history.length).to.equal(1);
+  });
+
+  it('should fail to go forward after navigating', () => {
+    history.goBack();
+    history.push(FIFTH_PATH);
+    history.goForward();
+    expect(history.location.pathname).to.equal(FIFTH_PATH);
+
+    history.goBack();
+    history.replace(SIXTH_PATH);
+    history.goForward();
+    expect(history.location.pathname).to.equal(FIFTH_PATH);
+  });
+
+  it('should add a listener', () => {
+    const listenerA = spy();
+    history.listen(listenerA);
+    history.goBack();
+    history.goForward();
+
+    const listenerB = spy();
+    history.listen(listenerB);
+    history.reset();
+    history.push(FIRST_PATH);
+    history.replace(SECOND_PATH);
+
+    expect(listenerA).to.have.been.called.exactly(5);
+    expect(listenerB).to.have.been.called.exactly(3);
+  });
+
+  it('should remove a listener', () => {
+    const listenerA = spy();
+    const removeListenerA = history.listen(listenerA);
+    history.goBack();
+    history.goForward();
+
+    const listenerB = spy();
+    history.listen(listenerB);
+    history.reset();
+
+    removeListenerA();
+    history.push(FIRST_PATH);
+    history.replace(SECOND_PATH);
+
+    expect(listenerA).to.have.been.called.exactly(3);
+    expect(listenerB).to.have.been.called.exactly(3);
+  });
+
+  it('should only remove listener once', () => {
+    const listenerA = spy();
+    const removeListenerA = history.listen(listenerA);
+    history.goBack();
+
+    const listenerB = spy();
+    history.listen(listenerB);
+    history.goForward();
+
+    removeListenerA();
+    removeListenerA();
+
+    history.reset();
+
+    expect(listenerA).to.have.been.called.exactly(2);
+    expect(listenerB).to.have.been.called.exactly(2);
+  });
+});