feat(effects): allow ofType to handle ActionCreator

[alex-okrushko]

PR Checklist

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• The commit message follows our guidelines: https://github.com/ngrx/platform/blob/master/CONTRIBUTING.md#commit
• Tests for the changes have been added (for bug fixes / features)
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PR Type

What kind of change does this PR introduce?

[ ] Bugfix
[x] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Documentation content changes
[ ] Other... Please describe:

What is the current behavior?

Closes #

What is the new behavior?

Allows to filter Actions with ofType(actionCreator) as well as maintains previous behavior ofType(actionCreator.type).

Does this PR introduce a breaking change?

[ ] Yes
[x] No

Other information

[ngrxbot]

Preview docs changes for 8549f84 at https://previews.ngrx.io/pr1676-8549f84/

[timdeschryver]

What about checking on action first and next on the action creator type?

return allowedTypes.some(type => {
  // Comparing the string to type
  if (typeof type === 'string') {
    return type === action.type;
  }

  // We are filtering by ActionCreator
  return type && type.type === action.type;
});

[alex-okrushko]

You are right, reads much better. Also I think I reimplemented some in my previous solution 🤦‍♂️

[ngrxbot]

Preview docs changes for 531d115 at https://previews.ngrx.io/pr1676-531d115/

[timdeschryver]

👍 LGTM

Right now this offers type safety for 5 action types.
This was due to the fact that we had to provide the typings.
If we want, we could add new typings as in the ts-action-operators library of Nicholas.
See https://github.com/cartant/ts-action-operators#oftype for ref.

 ofType({ foo, bar }),
  tap(action => {
    // Here, the action has been narrowed to `typeof union({ foo, bar })`.
    // Common properties will be accessible, other will require further narrowing.
    if (isType(action, foo)) {
      // Here, the action has been narrowed to a FOO action.
    } else if (isType(action, bar)) {
      // Here, the action has been narrowed to a BAR action.
    }
  })