When this test was failing, it would cause no future tests to run. This
was because the `expect` call within the `page.on` callback would throw
an error, and that would trigger a unhandled promise rejection that
caused the test framework to stop.
The fundamental issue here is making `expect` calls within callbacks.
They are brittle due to the fact that they throw, and the test framework
won't catch it, but also because you have no guarantee that they will
run. If the callback is never executed you dont' know about it.
Although it's slightly more code, using a stub is the way to do this.
Not only can we assert that the stub was called, we can make synchronous
`expect` calls that Mocha will pick up properly if they fail.
Before this change, running the tests (and making it fail on purpose)
would cause all test execution to stop:
```
> puppeteer@3.0.4-post unit /Users/jacktfranklin/src/puppeteer
> mocha --config mocha-config/puppeteer-unit-tests.js
.(node:69580) UnhandledPromiseRejectionWarning: Error: expect(received).toBe(expected) // Object.is equality
Expected: "yes."
Received: ""
at Page.<anonymous> (/Users/jacktfranklin/src/puppeteer/test/dialog.spec.js:42:37)
[snip]
(node:69580) UnhandledPromiseRejectionWarning: Unhandled promise rejection ... [snip]
```
But with this change, the rest of the tests run:
```
> puppeteer@3.0.4-post unit /Users/jacktfranklin/src/puppeteer
> mocha --config mocha-config/puppeteer-unit-tests.js
Page.Events.Dialog
✓ should fire
1) should allow accepting prompts
✓ should dismiss the prompt
2 passing (2s)
1 failing
1) Page.Events.Dialog
should allow accepting prompts:
Error: expect(received).toBe(expected) // Object.is equality
Expected: "yes."
Received: ""
at Context.<anonymous> (test/dialog.spec.js:53:35)
at processTicksAndRejections (internal/process/task_queues.js:94:5)
```
This is much better because one failing test now doesn't stop the rest
of the test suite.
This probably isn't the only instance of this in the codebase so I
propose as we encounter them we fix them usng this commit as the
template.
We have some bug where some test runs will pass but then stall as Mocha
doesn't exit cleanly. This is proving very hard to track down (I've yet
to replicate it or find the test that causes it) and it doesn't happen
consistently.
The `exit` flag forces Mocha to hard exit. This will help with CI
stability. The flag only gets set on CI runs.
Sticking to a specific version of TS rather than a ^ version so we know
everyone is on the exact same version. Think that's preferable for such
an important dependency.
* chore: extract `BrowserRunner` into its own module
`src/Launcher.ts` is large and hard to work in. It has multiple objects
defined in it:
* ChromeLauncher
* FirefoxLauncher
* BrowserRunner
* Launcher
This change moves BrowserRunner into its own module. More refactorings
like this will follow but this is the first step.
* Warn when given unsupported product name.
Fixes#5844.
This change means when a user launches Puppeteer with a product name
that is not supported (which at the time of this commit means it's not
`firefox` or `chrome) we will warn them about it.
Decided on just a warning vs an error because the current behaviour is
that we fallback to launching Chrome and I don't think this warrants a
breaking change.
Now the first pass of migrating to TypeScript is complete I'm going
through the src files one by one to tidy up the public/private
interfaces.
Puppeteer used an underscore convention to denote privacy but violates
this in some places; we should be strict with TypeScript's `public` and
`private` keywords instead.
This means we'll get nice TS errors if you try to refer to a private
method/variable, and means when we swap to generating our TS docs the
tooling knows what method(s) are public and therefore need to be
documented vs private internals that don't.
* chore: Remove src/TaskQueue
The only place it's used is in `src/Page.ts` to have a chain of
screenshot promises. Rather than initialize a task queue in `Browser`
and pass it through a chain of constructors we instead move the class
into `src/Page` and define it inline.
In the future we might want to create a helpers folder to contain small
utilities like that (`src/Page.ts` is already far too large) but I'm
leaving that for a future PR.
`TaskQueue` isn't documented in `api.md` so I don't think this is a
breaking change.
I updated the type of `screenshot()` to return `Promise<string | Buffer
| void>` because if a promise rejects it's silently swallowed. I'd like
to change this behaviour but one step at a time. This type only had to
change as now we type the screenshot task queue correctly rather than
using `any` which then exposed the incorrect `screenshot()` types.
closes#5719
Original stream.pipeline issue has been fixed in Node 14.1.0 and above.
Meanwhile, the workaround itself caused timout failures in many CI Node 14 runs, as reported in #5719.
Removed it, as it's no longer needed, and actually blocks consumers from adding CI testing on Node 14.
* chore: remove src/externs.d.ts
It defined global types that we don't want to use, and instead we move
to using interfaces that we import and reference just like with any
other interface.
This means other than Protocol (which I think is fine to leave as is),
there are no other magic global types and you have to import any types
or interfaces that you want.
* chore: migrate src/Page.js to TypeScript
The final one! This is a huge file and needs to be split up and tidied,
but for now I've left all the definitions in place and converted types
accordingly.
There's some additional tidying we can do now every `src` file is TS,
but I'll leave that for another PR to avoid this one getting any bigger.
Co-authored-by: Mathias Bynens <mathias@qiwi.be>
* chore: update how we track coverage during unit tests
The old method of tracking coverage was causing issues. If a test failed
on CI, that test's failure would be lost because the test failing would
in turn cause the coverage to fail, but the `process.exit(1)` in the
coverage code caused Mocha to not output anything useful.
Instead the coverage checker now:
* tracks the coverage in memory in a Map (this hasn't changed)
* after all tests, writes that to disk in test/coverage.json (which is
gitignored)
* we then run a single Mocha test that asserts every method was called.
This means if the test run fails, the build will fail and give the error
about that test run, and that output won't be lost when the coverage
then fails too.
Co-authored-by: Mathias Bynens <mathias@qiwi.be>
This change enforces how we type arrays, e.g. choosing between:
* `string[]`
* `Array<string>`
I've gone for the `array-simple` option [1] which enforces that:
* primitive types and type references use `X[]`
* complex types use `Array<X>`
For example, we'd type an array of strings as `string[]`, but an array
of a union type as `Array<SomeUnionType>`.
[1]: https://github.com/typescript-eslint/typescript-eslint/blob/master/packages/eslint-plugin/docs/rules/array-type.md
