pdf.js/external/builder/fixtures_esprima/deadcode.js
Nicolò Ribaudo f724ae98a1
Replace the webpack+acorn transform with a Babel plugin
This commit converts the pdfjsdev-loader transform into a Babel plugin,
to skip a AST->string->AST round-trip.

Before this commit, the webpack build process was:
1. Babel parses the code
2. Babel transforms the AST
3. Babel generates the code
4. Acorn parses the code
5. pdfjsdev-loader transforms the AST
6. @javascript-obfuscator/escodegen generates the code
7. Webpack parses the file
8. Webpack concatenates the files

After this commit, it is reduced to:
1. Babel parses the code
2. Babel transforms the AST
3. babel-plugin-pdfjs-preprocessor transforms the AST
4. Babel generates the code
5. Webpack parses the file
6. Webpack concatenates the files

This change improves the build time by ~25% (tested on MacBook Air M2):
- `gulp lib`: 3.4s to 2.6s
- `gulp dist`: 36s to 29s
- `gulp generic`: 5.5s to 4.0s
- `gulp mozcentral`: 4.7s to 3.2s

The new Babel plugin doesn't support the `saveComments` option of
pdfjsdev-loader, and it just always discards comments. Even though
pdfjsdev-loader supported multiple values for that option, it was
effectively ignored due to `acorn` dropping comments by default.
2024-01-23 16:00:59 +01:00

38 lines
462 B
JavaScript

function f1() {
return;
var i = 0;
}
function f2() {
return 1;
var i = 0;
}
function f3() {
var i = 0;
throw "test";
var j = 0;
}
function f4() {
var i = 0;
if (true) {
return;
}
throw "test";
var j = 0;
}
var obj = {
method1() { return; var i = 0; },
method2() { return; },
};
class C {
method1() { return; var i = 0; }
method2() { return; }
}
var arrow1 = () => { return; var i = 0; };
var arrow2 = () => { return; };