rafa/test/unit/core/Stream-scan.js

Rafa.js is a Javascript framework for building concurrent applications.

module.exports = (assert, Rafa) => {
  suite("scan", () => {
    test("emit values from scanner", () => {
      var values = [];
      var stream = Rafa.stream();
      
      stream.scan(1, (a,b) => a + b).each(v => values.push(v));
      stream.write(1).write(2);

      assert.equal(values.length, 2);
      assert.equal(values[0], 2);
      assert.equal(values[1], 4);

    });

    test("errors pass through", () => {
      var values = [];
      var stream = Rafa.stream();
      stream.scan(1, (a,b) => a + b).error(v => values.push(v));
      stream.write(new Error("oops"));
      assert.isNotNull(values[0]);
      assert.equal(values[0].message, "oops");
    });

  });
};