The simplify plugin seems to place variables declared and initialized before a while loop into a for loop, even if the variable is used again after the loop.
versions
babel-preset-minify@0.2.0
babel-cli@6.26.0
.babelrc
{
"presets": [
["env", {"targets":{"browsers":["last 2 versions"]}}],
["minify", {}]
]
}
Input Code
(function() {
let count = 10;
while (count++ < 20) {}
return count;
})();Actual Output
npx babel test.js --out-file test.min.js
"use strict";(function(){for(var a=10;20>a++;);return count})();This gives a Uncaught ReferenceError: count is not defined(…).
Expected Output
"use strict";(function(){var a=10;while(20>a++){}return a})();Details
It works as expected if I disabled the simplify plugin:
{
"presets": [
["env", {
"modules": false,
"targets":{
"browsers": ["last 2 version"]
}
}],
["minify", {
"simplify": false
}]
]
}
It also works if I change the input code as follows:
```js
(function() {
let count = 10;
0;
while (count++ < 20) {}
return count;
})();
Also, this
(function(x) {
let count = 10;
while (x++ < 20) {}
return count;
})(5);becomes
"use strict";(function(a){for(;20>a++;);return count})(5);which removes the variable initialization to 10 completely.
This one also happens on babeljs.io. It works correctly if I either turn off all presets or minify.
The simplify plugin seems to place variables declared and initialized before a while loop into a for loop, even if the variable is used again after the loop.
versions
.babelrc
Input Code
Actual Output
This gives a
Uncaught ReferenceError: count is not defined(…).Expected Output
Details
It works as expected if I disabled the simplify plugin:
Also, this
becomes
which removes the variable initialization to 10 completely.
This one also happens on babeljs.io. It works correctly if I either turn off all presets or minify.