larry babby and threejs for glsl

webGl/my-threejs-test/node_modules/@parcel/events/test/ValueEmitter.test.js

@@ -0,0 +1,100 @@
+// @flow strict-local
+
+import assert from 'assert';
+import ValueEmitter from '../src/ValueEmitter';
+import {AlreadyDisposedError} from '../src/errors';
+
+describe('ValueEmitter', () => {
+  let emitter: ValueEmitter<number>;
+  let values: Array<number>;
+
+  beforeEach(() => {
+    emitter = new ValueEmitter();
+    values = [];
+  });
+
+  afterEach(() => {
+    emitter.dispose();
+  });
+
+  function numberListener(x: number): void {
+    values.push(x);
+  }
+
+  it('registers new listeners and can dispose of them', () => {
+    let disposable = emitter.addListener(numberListener);
+    assert.deepEqual(emitter._listeners, [numberListener]);
+
+    disposable.dispose();
+    assert.deepEqual(emitter._listeners, []);
+  });
+
+  it('emits values to registered listeners', () => {
+    let disposable = emitter.addListener(numberListener);
+    emitter.emit(42);
+    assert.deepEqual(values, [42]);
+
+    disposable.dispose();
+  });
+
+  it('does not emit to listeners that were just registered', () => {
+    let innerDisposable;
+    let disposable = emitter.addListener(() => {
+      innerDisposable = emitter.addListener(numberListener);
+    });
+
+    emitter.emit(42);
+    assert.deepEqual(values, []);
+
+    emitter.emit(27);
+    assert.deepEqual(values, [27]);
+
+    disposable.dispose();
+    innerDisposable && innerDisposable.dispose();
+  });
+
+  it('finishes emitting even if a listener disposes of the emitter mid-emit', () => {
+    let disposableA = emitter.addListener(() => {
+      emitter.dispose();
+    });
+
+    let disposableB = emitter.addListener(numberListener);
+
+    emitter.emit(42);
+    assert.deepEqual(values, [42]);
+
+    disposableA.dispose();
+    disposableB.dispose();
+  });
+
+  it('clears listeners when disposed', () => {
+    let disposable = emitter.addListener(numberListener);
+    assert.deepEqual(emitter._listeners, [numberListener]);
+
+    emitter.dispose();
+    assert.deepEqual(emitter._listeners, []);
+
+    disposable.dispose();
+  });
+
+  it('throws when adding a listener when already disposed', () => {
+    emitter.dispose();
+    assert.throws(() => {
+      emitter.addListener(numberListener);
+    }, AlreadyDisposedError);
+  });
+
+  it('throws when emitting when already disposed', () => {
+    emitter.dispose();
+    assert.throws(() => {
+      emitter.emit(42);
+    }, AlreadyDisposedError);
+  });
+
+  it('can be disposed multiple times', () => {
+    emitter.dispose();
+    assert.doesNotThrow(() => {
+      emitter.dispose();
+    });
+  });
+});