Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

takeUntil #258

Open
wants to merge 3 commits into
base: master
Choose a base branch
from
Open

takeUntil #258

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
0858c1d
takeUntil but test isnt working
ccorcos Mar 29, 2015
72cb224
takeUntil test works
ccorcos Mar 29, 2015
c33dd7e
takeUntil better tests
ccorcos Mar 30, 2015
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
58 changes: 58 additions & 0 deletions lib/index.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -3554,6 +3554,64 @@ Stream.prototype.debounce = function (ms) {
};
exposeMethod('debounce');


/**
* Ends a source stream when a given stream ends or emits a value.
*
* @id takeUntil
* @section Higher-order Streams
* @name Stream.takeUntil(stream)
* @param {Stream} stream - another stream which stops the source
* @api public
*
* a = _()
* b = _()
* a.takeUntil(b)
* a.each(_.log)
* a.write(1)
* // => 1
* a.write(2)
* // => 2
* b.write(1)
* // nothing
* a.write(3)
* // nothing
*/

Stream.prototype.takeUntil = function (stream) {
if (!_.isStream(stream)) {
throw new Error('Invalid stream to takeUntil:', stream);
}
var first = true,
done = false;

return this.consume(function (err, x, push, next) {
if (first) {
stream.pull(function() {
if (!done) {
push(null, _.nil);
done = true;
}
});
first = false;
}
if (err) {
push(err);
next();
}
else if (x === _.nil) {
done = true;
push(null, x);
}
else if (!done) {
push(null, x);
next();
}
});
};
exposeMethod('takeUntil');


/**
* Creates a new Stream, which when read from, only returns the last
* seen value from the source. The source stream does not experience
Expand Down
124 changes: 124 additions & 0 deletions test/test.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1545,6 +1545,130 @@ exports['wrap EventEmitter (or jQuery) on handler with args wrapping by array']
});
};


exports['takeUntil'] = {
setUp: function (callback) {
this.clock = sinon.useFakeTimers();
callback();
},
tearDown: function (callback) {
this.clock.restore();
callback();
},
'invalid stream': function (test) {
test.throws(function () {
_([1,2,3]).takeUntil(10);
});
test.done();
},
'async generator': function (test) {
function delay(push, ms, x) {
setTimeout(function () {
push(null, x);
}, ms);
}
var source = _(function (push, next) {
delay(push, 10, 1);
delay(push, 20, 2);
delay(push, 30, 3);
// should be stopped
delay(push, 40, 4);
delay(push, 50, 5);
delay(push, 60, _.nil);
})
var stopStream = _(function (push, next) {
delay(push, 25, 1);
delay(push, 35, _.nil);
})
var results = [];
source.takeUntil(stopStream).each(function (x) {
results.push(x);
});
this.clock.tick(10);
test.same(results, [1]);
this.clock.tick(10);
test.same(results, [1, 2]);
this.clock.tick(10);
test.same(results, [1, 2, 3]);
this.clock.tick(10);
test.same(results, [1, 2, 3]);
this.clock.tick(20);
test.same(results, [1, 2, 3]);
test.done();
},
'toplevel - async generator': function (test) {
function delay(push, ms, x) {
setTimeout(function () {
push(null, x);
}, ms);
}
var source = _(function (push, next) {
delay(push, 10, 1);
delay(push, 20, 2);
delay(push, 30, 3);
// should be stopped
delay(push, 40, 4);
delay(push, 50, 5);
delay(push, 60, _.nil);
})
var stopStream = _(function (push, next) {
delay(push, 25, 1);
delay(push, 35, _.nil);
})
var results = [];
_.takeUntil(stopStream, source).each(function (x) {
results.push(x);
});
this.clock.tick(10);
test.same(results, [1]);
this.clock.tick(10);
test.same(results, [1, 2]);
this.clock.tick(10);
test.same(results, [1, 2, 3]);
this.clock.tick(10);
test.same(results, [1, 2, 3]);
this.clock.tick(20);
test.same(results, [1, 2, 3]);
test.done();
},
'toplevel - partial application, async generator': function (test) {
function delay(push, ms, x) {
setTimeout(function () {
push(null, x);
}, ms);
}
var source = _(function (push, next) {
delay(push, 10, 1);
delay(push, 20, 2);
delay(push, 30, 3);
// should be stopped
delay(push, 40, 4);
delay(push, 50, 5);
delay(push, 60, _.nil);
})
var stopStream = _(function (push, next) {
delay(push, 25, 1);
delay(push, 35, _.nil);
})
var results = [];
_.takeUntil(stopStream)(source).each(function (x) {
results.push(x);
});
this.clock.tick(10);
test.same(results, [1]);
this.clock.tick(10);
test.same(results, [1, 2]);
this.clock.tick(10);
test.same(results, [1, 2, 3]);
this.clock.tick(10);
test.same(results, [1, 2, 3]);
this.clock.tick(20);
test.same(results, [1, 2, 3]);
test.done();
},
'noValueOnError': noValueOnErrorTest(_.takeUntil(_()))
};

exports['sequence'] = function (test) {
_.sequence([[1,2], [3], [[4],5]]).toArray(function (xs) {
test.same(xs, [1,2,3,[4],5]);
Expand Down