Test Observable.first;

tests/first.lua

@@ -0,0 +1,19 @@
+describe('first', function()
+  it('produces an error if its parent errors', function()
+    local observable = Rx.Observable.fromValue(''):map(function(x) return x() end)
+    expect(observable.subscribe).to.fail()
+    expect(observable:first().subscribe).to.fail()
+  end)
+
+  it('produces no elements if its parent produces no elements', function()
+    local observable = Rx.Observable.create(function(observer) return observer:onComplete() end):first()
+    expect(observable).to.produce({})
+  end)
+
+  it('produces the first element of its parent and immediately completes', function()
+    local observable = Rx.Observable.fromRange(5):first()
+    expect(observable).to.produce(1)
+  end)
+end)
+
+

tests/observable.lua

@@ -157,4 +157,5 @@ describe('Observable', function()
   dofile('tests/distinct.lua')
   dofile('tests/filter.lua')
   dofile('tests/find.lua')
+  dofile('tests/first.lua')
 end)