@Boshen
The `ScopeTree.descendants` function would return all scopes starting
from the root, and wasn't truly descendants from a specific scope. To
improve this, I've renamed this function to `descendants_from_root` and
have introduced a new `descendants` function that does support from a
specific scope.
Furthermore, I've introduced helper functions to `SymbolTree` to make
reading symbols/scopes easier.
To verify this functionality, I enabled the `function_name` transformer
(and fixed it), and ran some example transforms. Here's the input:
```js
let fn;
fn = function (a, b, c) {
const d = "";
};
const func = function (arg) {
{
const value = "";
}
};
const f = function (f) {};
```
And the output using _the old implementation_. Note that all function
names are suffixed with a number, this is incorrect, since it was
inheriting far too many scopes.
```js
let fn;
fn = function fn1(a, b, c) {
const d = '';
};
const func = function func1(arg) {
{
const value = '';
}
};
const f = function f2(f) {
};
```
And here's the output with the new implementation. Note that only `f` is
suffixed with a number. That's because it has a shadowed argument of the
same name.
```js
let fn;
fn = function fn(a, b, c) {
const d = '';
};
const func = function func(arg) {
{
const value = '';
}
};
const f = function f1(f) {
};
```
This PR introduces the oxc transformer.
The code is purposely arranged without any Rust trickery such as traits
and macros.
I intend to keep the code style this way until something blows up.
The next steps are:
* unit tests
* conformance tests with TypeScript and Babel
* benchmarks
