@testim/testim-cli
Version:
Command line interface for running Testing on you CI
40 lines (39 loc) • 1.57 kB
JavaScript
/**
* Applies an accumulator function over an observable sequence, returning the result of the aggregation as a single element in the result sequence. The specified seed value is used as the initial accumulator value.
* For aggregation behavior with incremental intermediate results, see Observable.scan.
* @param {Function} accumulator An accumulator function to be invoked on each element.
* @param {Any} [seed] The initial accumulator value.
* @returns {Observable} An observable sequence containing a single element with the final accumulator value.
*/
observableProto.reduce = function (accumulator) {
var hasSeed = false, seed, source = this;
if (arguments.length === 2) {
hasSeed = true;
seed = arguments[1];
}
return new AnonymousObservable(function (o) {
var hasAccumulation, accumulation, hasValue;
return source.subscribe (
function (x) {
!hasValue && (hasValue = true);
try {
if (hasAccumulation) {
accumulation = accumulator(accumulation, x);
} else {
accumulation = hasSeed ? accumulator(seed, x) : x;
hasAccumulation = true;
}
} catch (e) {
o.onError(e);
}
},
function (e) { o.onError(e); },
function () {
hasValue && o.onNext(accumulation);
!hasValue && hasSeed && o.onNext(seed);
!hasValue && !hasSeed && o.onError(new EmptyError());
o.onCompleted();
}
);
}, source);
};