* fix(typescript): remove parens from union types where possible, fixes#1885
* fix(typescript): ensure parenthesis removal is stable
* fix(typescript): don't strip parens around function type
- I want to get to a place where we don't use ast-types in order to do the traversal. This almost removes it from fast-path.
- Remove FastPath.from and copy
- Use .prototype instead of the weird Fpp
- Remove unused TODO
- Remove unused needsParen condition with a bunch of associated code
* Improve ESLint setup
- Uses `eslint:recommended` + a handful more rules.
- Uses .eslintignore so that editors can understand which files to lint.
- Uses .eslintrc<strong>.js</strong> so more editors get syntax highlighting.
* Fix ESLint errors
About half of them were fixed by `eslint . --fix`.
* Use `const`/`let` instead of `var`
This was done with [lebab], by running:
lebab --replace src -t let
[lebab]: https://github.com/lebab/lebab
* Remove remaining `var` usages
These were not automatically fixed by `lebab`, so they had to be
manually refactored.
* fix(typescript): improve handling of computed properties
* test(typescript): add Symbol computed property test
* fix(typescript): do not print brackets for literals
This was added in order to follow some eslint rule but it's only confusing when it doesn't break, when it breaks the indentation makes it clear what is happening and you don't need parenthesis.
Fixes#1379
* Add eslint as dev dep, reorder scripts.
* Add tests & docs to eslintignore.
* Add eslintcache to gitignore.
* Update yarn lock file 😽.
* Add linting step in the test pipeline.
* Add a set of really basic rules for linting.
* Fix linting 🚀.
* No need for .jsx files to be linted...
* Reorder rules alphabetically.
* Refine rules: drop styling ones, only keep what provides dead code elimination.
* Add no-console rule to be consistent along with the no-debugger one.
* Remove empty line.
* Add eslint-disable-next-line no-console where console log/warn/error are allowed.
* Drop no-console rule.
* Remove eslint-disable-next-line no-console comments.
* Remove linting step in Travis CI.
* Fix linting after merging current master.
* Run `npm test -- -u` after noticing one test was out of sync.
* Drop eslint references from previous implementation.
* Revert yarn lock file.
* Revert scripts ordering.
* Fix incorrect yarn lock file.
I'm unclear whether anyone was ever confused by this but the eslint page is kind of compelling
```js
// The intent is not clear
var x = a => 1 ? 2 : 3;
// Did the author mean this
var x = function (a) { return 1 ? 2 : 3 };
// Or this
var x = a <= 1 ? 2 : 3;
```
Adding a parenthesis makes it valid with `{"allowParens": true}` rule. Note that if this option is not enabled, the code would not pass lint in the first place.