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

fix AST_Binary.lift_sequences() (#1621)

Browse Source 
Commit eab99a1c fails to account for side effects from compound assignments.
This commit is contained in:
Alex Lam S.L
2017-03-19 03:04:22 +08:00
committed by GitHub
parent 274331d0ea
commit cd58635dcc
2 changed files with 39 additions and 22 deletions
Download Patch File Download Diff File Expand all files Collapse all files

35
lib/compress.js
View File

@@ -2999,14 +2999,6 @@ merge(Compressor.prototype, {
return self;
});
function has_side_effects_or_prop_access(node, compressor) {
var save_pure_getters = compressor.option("pure_getters");
compressor.options.pure_getters = false;
var ret = node.has_side_effects(compressor);
compressor.options.pure_getters = save_pure_getters;
return ret;
}
AST_Binary.DEFMETHOD("lift_sequences", function(compressor){
if (compressor.option("sequences")) {
if (this.left instanceof AST_Seq) {
@@ -3014,18 +3006,23 @@ merge(Compressor.prototype, {
var x = seq.to_array();
this.left = x.pop();
x.push(this);
seq = AST_Seq.from_array(x).transform(compressor);
return seq;
return AST_Seq.from_array(x).optimize(compressor);
}
if (this.right instanceof AST_Seq
&& this instanceof AST_Assign
&& !has_side_effects_or_prop_access(this.left, compressor)) {
var seq = this.right;
var x = seq.to_array();
this.right = x.pop();
x.push(this);
seq = AST_Seq.from_array(x).transform(compressor);
return seq;
if (this.right instanceof AST_Seq && !this.left.has_side_effects(compressor)) {
var assign = this.operator == "=" && this.left instanceof AST_SymbolRef;
var root = this.right;
var cursor, seq = root;
while (assign || !seq.car.has_side_effects(compressor)) {
cursor = seq;
if (seq.cdr instanceof AST_Seq) {
seq = seq.cdr;
} else break;
}
if (cursor) {
this.right = cursor.cdr;
cursor.cdr = this;
return root.optimize(compressor);
}
}
}
return this;