mirror of
https://github.com/danbulant/oxc
synced 2026-05-24 12:21:58 +00:00
c6ad6603a4
@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) {
};
```
|
||
|---|---|---|
| .. | ||
| examples | ||
| src | ||
| tests | ||
| Cargo.toml | ||
| README.md | ||
Minifier
A JavaScript minifier has three components:
- printer
- mangler
- compressor
Mangler
The mangler implementation is part of the SymbolTable residing in oxc_semantic.
It is responsible for shortening variables. Its algorithm should be gzip friendly.
The printer is also responsible for printing out the shortened variable names.
Compressor
The compressor is responsible for rewriting statements and expressions for minimal text output. Terser is a good place to start for learning the fundamentals.
Terser Tests
The fixtures are copied from https://github.com/terser/terser/tree/master/test/compress