Marble testing doc additions #4522
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doc/marble-testing.md
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| - `hot(marbleDiagram: string, values?: object, error?: any)` - creates a ["hot" observable](https://medium.com/@benlesh/hot-vs-cold-observables-f8094ed53339) (like a subject) that will behave as though it's already "running" when the test begins. An interesting difference is that `hot` marbles allow a `^` character to signal where the "zero frame" is. That is the point at which the subscription to observables being tested begins. | ||
| - `cold(marbleDiagram: string, values?: object, error?: any)` - creates a ["cold" observable](https://medium.com/@benlesh/hot-vs-cold-observables-f8094ed53339) whose subscription starts when the test begins. | ||
| - `expectObservable(actual: Observable<T>).toBe(marbleDiagram: string, values?: object, error?: any)` - schedules an assertion for when the TestScheduler flushes. Give `subscriptionMarbles` as parameter to change the schedule of subscription and unsubscription. If you don't provide the `subscriptionMarbles` parameter it will subscribe at the beginning and never unsubscribe. Read below about subscription marble diagram. | ||
| - `expectObservable(actual: Observable<T>, subscriptionMarbles: string).toBe(marbleDiagram: string, values?: object, error?: any)` - schedules an assertion for when the TestScheduler flushes. Give `subscriptionMarbles` as parameter to change the schedule of subscription and unsubscription. If you don't provide the `subscriptionMarbles` parameter it will subscribe at the beginning and never unsubscribe. Read below about subscription marble diagram. |
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The parameter is optional: subscriptionMarbles?: string
doc/marble-testing.md
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| expectObservable(repeatingStream$, unsub).toBe(results); | ||
| }); | ||
| }) | ||
| ``` |
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Could you make this a complete example? results is not defined.
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@whiteinge ... can you also add a example of using the subscription marbles to delay the subscription?
For example, given a hot source, you can subscribe to it more than once and verify the results:
testScheduler.run(({ hot, expectObservable }) => {
const source = hot('--a--a--a--a--a--a--a--');
const sub1 = ' --^-----------!';
const sub2 = ' ---------^--------!';
const expect1 = ' --a--a--a--a--';
const expect2 = ' -----------a--a--a-';
expectObservable(source, sub1).toBe(expect1);
expectObservable(source, sub2).toBe(expect2);
});Why: This is a complete example, as requested, and also more plain to demonstrate just the one param.
whiteinge
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Will the change log bot ignore those two fixup commits? Or should I rebase them into their respective initial commits? |
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All of the commits in here are so closely related that I would expect the person merging to squash them, so I wouldn't worry about it. |
doc/marble-testing.md
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| expectObservable(repeatingStream$, unsub).toBe(results); | ||
| }); | ||
| }) | ||
| ``` |
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@whiteinge ... can you also add a example of using the subscription marbles to delay the subscription?
For example, given a hot source, you can subscribe to it more than once and verify the results:
testScheduler.run(({ hot, expectObservable }) => {
const source = hot('--a--a--a--a--a--a--a--');
const sub1 = ' --^-----------!';
const sub2 = ' ---------^--------!';
const expect1 = ' --a--a--a--a--';
const expect2 = ' -----------a--a--a-';
expectObservable(source, sub1).toBe(expect1);
expectObservable(source, sub2).toBe(expect2);
});
Co-Authored-By: whiteinge <seth@eseth.com>
Example courtesy of @benlesh.
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Could you also move this document to docs_app/content/guide (not 100% sure about the path) and make a minor adjustment in the navigation.json file. That this change will directly be in the new docs! If you need any kind of help with this, just let me know. I would love to have this in the new docs, so thank you very much!
Also remove the redundant docs so contributors know where to look for the up-to-date canonical docs.
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@jwo719 done. Thanks for the pointer. I didn't realize there was a spot for those docs in the guide and that's a much better (and nicer looking) place. |
Description:
Additions and adjustments to the marble testing documentation. These additions emphasize the async helper functions, and also make the subscriptionMarbles parameter more explicit.
Related issue (if exists):
Closes #4521.