Declare more TS typings

[vidartf]

The current typescript code has a lot of anys (both explicit and implicit). These should be more explicitly typed, at least on the exported functions. A more explicit typing, maybe together with strict null checks might also reveal some bugs.

• no explicit any typings unless absolutely necessary
• no implicit any typings unless necessary
• turn on strict null checking

[jasongrout]

Sounds like an excellent sprint day project.

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On Thu, Aug 24, 2017, 07:12 Vidar Tonaas Fauske ***@***.***> wrote: The current typescript code has a lot of anys (both explicit and implicit). These should be more explicitly typed, at least on the exported functions. A more explicit typing, maybe together with strict null checks might also reveal some bugs. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#1672>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AALwZudyNRuv2mZ90yNfbH7cfegDHkUAks5sbVqtgaJpZM4PBPGA> .

[vidartf]

Yes, absolutely. If anybody wants to do it, that would be perfect, if not, I'll try to squeeze it in 😉

[cnishina]

Currently working on this. 😄

[cnishina]

Here is the examples that needs review. #1733

[vidartf]

@cnishina I did some work previously that stranded a bit, see #1734. Always meant to come back to it, but you know how it goes. If you are able to use that as a starting point to take further that would be awesome!

[cnishina]

@vidartf ☹️ I'm having some weird tsc errors that I did not get a few days ago. So I did an npm install in the main directory. I get the following error:

> @jupyter-widgets/[email protected] build:src /path/to/ipywidgets/packages/base
> tsc --project src

src/utils.ts(14,8): error TS2307: Cannot find module 'base64-js'.

That's weird, so I did an npm install -D @types/base64-js to add the typings from DefinitelyTyped. Then I get another error:

> @jupyter-widgets/[email protected] build:src /path/to/ipywidgets/packages/controls
> tsc --project src

src/phosphor/accordion.ts(10,8): error TS2307: Cannot find module '@phosphor/signaling'.
src/phosphor/currentselection.ts(14,8): error TS2307: Cannot find module '@phosphor/signaling'.
src/phosphor/tabpanel.ts(14,8): error TS2307: Cannot find module '@phosphor/signaling'.

Super weird. I did a brand new clone, install and came up with the same sort of errors. Is there something that I'm missing in the developer setup?

[vidartf]

Are you using the dev-install script? If not, what happens if you follow the appropriate steps manually?

[vidartf]

It seems a lot of this is being fixed in #1738.

[jasongrout]

Yes, it's weird that somehow these problems are just now being noticed.

[cnishina]

OOoOoOh... going to check it out.

[cnishina]

Back on track but now I have new problems. I can add some explicit typings in so there are no implicit any's; however, some of these issues might require some additional work. For example...looking at ipywidgets/packages/controls/widget_box.ts

• BoxView extends type DOMWidgetView
• DOMWidgetView has property pWidget. pWidget is type Widget
• in BoxView, the property pWidget is being set to JupyterPhosphorPanelWidget
• JupyterPhosphorPanelWidget extends type Panel and is cannot be of type Widget

🤔

[cnishina]

I also started to make ES6 changes to use fat arrows and let over var; however, this project appears to be set up as ES5 based on the tsconfig. In hind sight I probably should have clarified this first. Jupyter widgets is using ES5?

[jasongrout]

JupyterPhosphorPanelWidget extends type Panel and is cannot be of type Widget

Panel is a subclass of Widget: https://github.com/phosphorjs/phosphor/blob/23b9d075ebc5b73ab148b6ebfc20af97f85714c4/packages/widgets/src/panel.ts#L28

[jasongrout]

Jupyter widgets is using ES5?

Jupyter widgets is using Typescript. Typescript is configured to compile arrow functions and let down to ES5 for backwards compatibility.

I was hoping to go through and mak a pass changing var to let, using arrow functions, etc. If you want to do it, go for it! (perhaps on a separate PR to make reviewing easier?)

[cnishina]

I've been replacing that = this and using fat arrows, and let over var. I just realized my previous comment about ES5 is moot because the tsconfig is transpiling to ES5 but TypeScript does not care.

[blink1073]

Yep, we have been treating TypeScript as ES6 + type information, not really using the experimental features like decorators.

[jasongrout]

The other es6 thing I've been experimenting with is using async/await, though I try to use it sparingly since it makes the generated javascript harder to follow/debug.

[vidartf]

Fixed in #1734