[core] deprecate Toaster in favor of OverlayToaster

[adidahiya]

Changes proposed in this pull request:

Properly deprecate Toaster API in favor of OverlayToaster, for forwards-compatibility with v5.0. See https://github.com/palantir/blueprint/wiki/Toaster-5.0-changes

This is most commonly referenced in user code like this:

- const myToaster = Toaster.create();
+ const myToaster = OverlayToaster.create();

Also mark IToasterProps as deprecated, to be replaced by OverlayToasterProps. We can auto-fix this type with the no-deprecated-type-references lint rule, but we don't have the no-deprecated-components rule set up to auto-fix components right now.

[adidahiya]

[core] deprecate Toaster in favor of OverlayToaster

Build artifact links for this commit: documentation | landing | table | demo

This is an automated comment from the deploy-preview CircleCI job.

[dlech]

FYI, this is a breaking change, e.g. https://github.com/pybricks/pybricks-code/actions/runs/4989185014/jobs/8932767904?pr=1741#step:5:6

[adidahiya]

ah, sorry about that, thanks for flagging. I suppose I could fix this by changing it to:

Suggested change

	// eslint-disable-next-line @typescript-eslint/no-redeclare
	export type Toaster = ToasterInstance;
	// eslint-disable-next-line @typescript-eslint/no-redeclare
	export type Toaster = typeof OverlayToaster;

[adidahiya]

Opened a PR: #6165

[dlech]

It should probably just be deleted until v5 to avoid complications.

[adidahiya]

I don't think removing this line will be backwards-compatible.

Before, Toaster was a class, so it could be referenced as a type or a value.

After this change, it's re-exported as a value with const Toaster = OverlayToaster. But that will break existing usage of Toaster as a type (you could work around this with typeof Toaster).

To restore Toaster as a type in the public API, I think we need an export type Toaster = ... statement.

[dlech]

👍 makes sense.