JoBoEVD/UglifyJS
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

fix unused on labeled for-loop (#1831)

Browse Source 
fixes #1830
This commit is contained in:
Alex Lam S.L
2017-04-20 04:18:38 +08:00
committed by GitHub
parent 4dcff038cb
commit 88e7a542cd
2 changed files with 55 additions and 14 deletions
Download Patch File Download Diff File Expand all files Collapse all files

34
lib/compress.js
View File

@@ -2090,26 +2090,32 @@ merge(Compressor.prototype, {
return maintain_this_binding(tt.parent(), node, node.right.transform(tt));
}
}
// certain combination of unused name + side effect leads to:
// https://github.com/mishoo/UglifyJS2/issues/44
// https://github.com/mishoo/UglifyJS2/issues/1830
// that's an invalid AST.
// We fix it at this stage by moving the `var` outside the `for`.
if (node instanceof AST_For) {
descend(node, this);
if (node.init instanceof AST_BlockStatement) {
// certain combination of unused name + side effect leads to:
// https://github.com/mishoo/UglifyJS2/issues/44
// that's an invalid AST.
// We fix it at this stage by moving the `var` outside the `for`.
var body = node.init.body.slice(0, -1);
node.init = node.init.body.slice(-1)[0].body;
body.push(node);
return in_list ? MAP.splice(body) : make_node(AST_BlockStatement, node, {
body: body
});
var block = node.init;
node.init = block.body.pop();
block.body.push(node);
return in_list ? MAP.splice(block.body) : block;
} else if (is_empty(node.init)) {
node.init = null;
return node;
}
return node;
}
if (node instanceof AST_LabeledStatement && node.body instanceof AST_For) {
descend(node, this);
if (node.body instanceof AST_BlockStatement) {
var block = node.body;
node.body = block.body.pop();
block.body.push(node);
return in_list ? MAP.splice(block.body) : block;
}
return node;
}
if (node instanceof AST_Scope && node !== self)
return node;