We're seeing odd failures with Prettier on some CI branches; my hunch is that they are installing different versions of the package and therefore getting formatting conflicts. This PR updates them all and pins them to specific versions - something we should probably consider generally, or remove our `package-lock.json` from the gitignore.
* fix: make `$` and `$$` selectors generic
This means, much like TS's in built `querySelector` type, you can now do:
```ts
const listItems = page.$$<HTMLLIElement>('ul li');
```
And/or:
```ts
const h2 = page.$<HTMLHeadingElement>('h2');
```
And the return value will be of type `ElementHandle<T>|null`, where `T`
is the type you provided. By default `T` is an `Element`, so you don't
have to provide this if you don't care as a consumer about the exact
type you get back.
* chore: fix test assertions
During the migration to TS we changed `jsonValue` so it returned
`<Record<string, unknown>>`. This is only true if all the JSON values it
returns are objects; but it could return an array, a string, a number,
etc. Therefore we make the type generic, setting the default to
`unknown`, so the user has control over the type.
* chore: run unit tests on node 10.15
We saw in https://github.com/puppeteer/puppeteer/issues/6548 that the
`fs.promises` module was experimental in Node <10.17 and as such we
introduced issues for users on 10.15.
Until we can drop Node v10 (it's EOL is 30-04-20201
https://github.com/nodejs/Release#release-schedule) we should run our
tests on an old Node 10 to avoid regressing in this area.
* chore: helper for importing fs safely
In `src/common` we now use `fs.promises.X` which we can dynamically
`import`. In a browser environment this code will never run because it's
gated on `isNode` (in a future PR we will add tree-shaking to the bundle
step such that this code is eliminated). By using `import`, we ensure
TypeScript still can track types and give good type information.
In `src/node` we continue to use `util.promisify` but that's not a
concern as that code explicitly is never run in the browser.
This commit changes the internal representation of query handlers to contain Puppeteer-level code instead of page functions.
The interface `CustomQueryHandler` is introduced for user-defined query handlers. When a `CustomQueryHandler` is registered using `registerCustomQueryHandler` a corresponding Puppeteer-level handler is created through `makeQueryHandler` by wrapping the page functions as appropriate.
The internal query handlers (defined by the interface `QueryHandler`) contain two new functions: `waitFor` and `queryAllArray`.
- `waitFor` allows page-based handlers to make use of the `WaitTask`-backed implementation in `DOMWorld`, whereas purely Puppeteer-based handlers can define an alternative approach instead.
- `queryAllArray` is similar to `queryAll` but with a slightly different interface; it returns a `JSHandle` to an array with the results as opposed to an array of `ElementHandle`. It is used by `$$eval`.
After this change, we can introduce built-in query handlers that are not executed in the page context (#6307).
* chore: enforce file extensions on imports
To make our output agnostic it should include file extensions in the
output, as per the ESM spec. It's a bit odd for Node packages but makes
it easier to publish a browser build.
* chore: Use devtools-protocol package
Rather than maintain our own protocol we can instead use the devtools-protocol package and pin it to the version of Chromium that Puppeteer is shipping with.
The only changes are naming changes between the bespoke protocol that Puppeteer created and the devtools-protocol one.
This pulls in the types (based on the DefinitelyTyped repo) for
`page.$eval` (and the `$eval` method on other classes). The `$eval`
method is quite hard to type due to the way we wrap and unwrap
ElementHandles that are passed to / returned from the `pageFunction`
that users provide.
Longer term we can improve the types by providing type overloads as
DefinitelyTyped does but I've deferred that for now (see the `TODO` in
the code for more details).
This change started as a small change to pull types from DefinitelyTyped over to
Puppeteer for the `evaluateHandle` function but instead ended up also fixing
what looks to be a long standing issue with our existing documentation.
`evaluateHandle` can in fact return an `ElementHandle` rather than a `JSHandle`.
Note that `ElementHandle` extends `JSHandle` so whilst the docs are technically
correct (all ElementHandles are JSHandles) it's confusing because JSHandles
don't have methods like `click` on them, but ElementHandles do.
if you return something that is an HTML element:
```
const button = page.evaluateHandle(() => document.querySelector('button'));
// this is an ElementHandle, not a JSHandle
```
Therefore I've updated the original docs and added a large explanation to the
TSDoc for `page.evaluateHandle`.
In TypeScript land we'll assume the function will return a `JSHandle` but you
can tell TS otherwise via the generic argument, which can only be `JSHandle`
(the default) or `ElementHandle`:
```
const button = page.evaluateHandle<ElementHandle>(() => document.querySelector('button'));
```
* feat(types): improve typing of `.evaluate()`
This is the start of the work to take the types from the
`@types/puppeteer` repository and port them into our repo so we can ship
our built-in types out the box.
This change types the `evaluate` function properly. It takes a generic
type which is the type of the function you're passing, and the arguments
and the return that you get back from the `evaluate` call are typed
correctly.
This CL migrates all the tests to TypeScript. The main benefits of this is that we start consuming our TypeScript definitions and therefore find errors in them. The act of migrating found some bugs in our definitions and now we can be sure to avoid them going forwards.
You'll notice the addition of some `TODO`s in the code; I didn't want this CL to get any bigger than it already is but I intend to follow those up once this lands. It's mostly figuring out how to extend the `expect` types with our `toBeGolden` helpers and some other slight confusions with types that the tests exposed.
Co-authored-by: Mathias Bynens <mathias@qiwi.be>
These files will be used by both the web and node versions of Puppeteer.
Another name for this might be "core" but I don't want to cause
confusion with the puppeteer-core package that we publish at the moment.
