* [refactor] Migrate from Mocha+Chai to Jest
This change migrates all the existing unit tests
- to Jest's global expect and matchers from chai's imported expect, asserts and matchers.
- to Jest's describe/test from mocha's describe/it
The majority of the mechanical changes to tests are achieved through running jest-codemods. The only two note-worthy manual tweaks:
1. Setting a testURL of http://localhost in jest config and adjusting a few tests to leverage this value instead of relying on about:blank.
2. Re-enabling ExploreChartPanel_spec which was previously commented out as we cannot have empty tests with nothing in it with Jest. :)
This change also removes dependencies to Mocha and Chai.
* Remove the test:one command as it now does the same thing as test.
* Fixing lint errors. The diff looks large but is large done through `yarn run lint --fix`
The only noteworthy change is the one in eslintrc for tests. The env has been updated from mocha to jest.
* Adding eslint-plugin-jest and further modify tests.
- One small fix in sqllab's Timer Spec for a test that is not using the spy it created for testing.
- Deletion of a duplicated test caught by eslint-plugin-jest.
* - Make istanbul coverage work with Jest.
- Remove dependency on stand-alone istanbul and babel-istanbul as they're built-into jest. Yes!
* Attempt to fix dynamic imports in tests.
* run sequentially and log heap usage
* - tweaking maxworkers for travis and specifying coverageDirectory for codecov
- remove dynamic import in shim.js now that it is set in babelrc for tests only.
Introducing a nice component as a label that show when data was
loaded from cache, when the cache was taken (in humanize duration as in
`a few minutes ago`) in a tooltip, and it can act as a button that
can trigger a force-refresh.
While working on it, it became clear that it was going to be hard to
use this component in the Dashboard view since it's not pure React.
I'm planning on refactoring the dashboard view with proper React/Redux
and introducing the CachedLabel component at that point.
While digging around in the Dashboard view I realized that there was a
bunch on unused code around managing timers that was used in explorev1
and decided to rip it out.
