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Test Info: Warnings
- This test has a WPT meta file that expects 7 subtest issues.
- This WPT test may be referenced by the following Test IDs:
- /dom/observable/tentative/observable-drop.any.html - WPT Dashboard Interop Dashboard
- /dom/observable/tentative/observable-drop.any.worker.html - WPT Dashboard Interop Dashboard
test(() => {
const source = new Observable(subscriber => {
subscriber.next(1);
subscriber.next(2);
subscriber.next(3);
subscriber.next(4);
subscriber.complete();
});
const results = [];
source.drop(2).subscribe({
next: v => results.push(v),
error: e => results.push(e),
complete: () => results.push("complete"),
});
assert_array_equals(results, [3, 4, "complete"]);
}, "drop(): Observable should skip the first n values from the source " +
"observable, then pass through the rest of the values and completion");
test(() => {
const error = new Error('source error');
const source = new Observable(subscriber => {
subscriber.next(1);
subscriber.next(2);
subscriber.next(3);
subscriber.next(4);
subscriber.error(error);
});
const results = [];
source.drop(2).subscribe({
next: v => results.push(v),
error: e => results.push(e),
complete: () => results.push("complete"),
});
assert_array_equals(results, [3, 4, error]);
}, "drop(): Observable passes through errors from source Observable");
test(() => {
const error = new Error('source error');
const source = new Observable(subscriber => {
subscriber.error(error);
subscriber.next(1);
});
const results = [];
source.drop(2).subscribe({
next: v => results.push(v),
error: e => results.push(e),
complete: () => results.push("complete"),
});
assert_array_equals(results, [error]);
}, "drop(): Observable passes through errors from source observable even " +
"before drop count is met");
test(() => {
const source = new Observable(subscriber => {
subscriber.next(1);
subscriber.complete();
});
const results = [];
source.drop(2).subscribe({
next: v => results.push(v),
error: e => results.push(e),
complete: () => results.push("complete"),
});
assert_array_equals(results, ["complete"]);
}, "drop(): Observable passes through completions from source observable even " +
"before drop count is met");
test(() => {
let sourceTeardownCalled = false;
const source = new Observable(subscriber => {
subscriber.addTeardown(() => sourceTeardownCalled = true);
subscriber.next(1);
subscriber.next(2);
subscriber.next(3);
subscriber.next(4);
subscriber.next(5);
subscriber.complete();
});
const results = [];
const controller = new AbortController();
source.drop(2).subscribe({
next: v => {
results.push(v);
if (v === 3) {
controller.abort();
}
},
error: (e) => results.push(e),
complete: () => results.push("complete"),
}, {signal: controller.signal});
assert_true(sourceTeardownCalled,
"Aborting outer observable unsubscribes the source observable");
assert_array_equals(results, [3]);
}, "drop(): Unsubscribing from the Observable returned by drop() also " +
"unsubscribes from the source Observable");
test(() => {
const source = new Observable(subscriber => {
subscriber.next(1);
subscriber.next(2);
subscriber.next(3);
subscriber.complete();
});
const results = [];
source.drop(0).subscribe({
next: v => results.push(v),
error: e => results.push(e),
complete: () => results.push("complete"),
});
assert_array_equals(results, [1, 2, 3, "complete"],
"Source Observable is mirrored");
}, "drop(): A drop amount of 0 simply mirrors the source Observable");
test(() => {
const source = new Observable(subscriber => {
subscriber.next(1);
subscriber.next(2);
subscriber.next(3);
subscriber.complete();
});
const results = [];
// Passing `-1` here is subject to the Web IDL integer conversion semantics,
// which converts the drop amount to the maximum of `18446744073709551615`.
source.drop(-1).subscribe({
next: v => results.push(v),
error: e => results.push(e),
complete: () => results.push("complete"),
});
assert_array_equals(results, ["complete"], "Source Observable is mirrored");
}, "drop(): Passing negative value wraps to maximum value ");