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

enhance side_effects (#4727)

Browse Source
This commit is contained in:
Alex Lam S.L
2021-03-03 10:47:17 +00:00
committed by GitHub
parent 04ed818f0a
commit 2a49760032
6 changed files with 64 additions and 43 deletions
Download Patch File Download Diff File Expand all files Collapse all files

59
lib/compress.js
View File

@@ -4797,9 +4797,15 @@ merge(Compressor.prototype, {
|| this.right.has_side_effects(compressor);
});
def(AST_Binary, function(compressor) {
return this.left.has_side_effects(compressor)
|| this.right.has_side_effects(compressor)
|| this.operator == "in" && !is_object(this.right);
var lhs = this.left;
if (lhs.has_side_effects(compressor)) return true;
var rhs = this.right;
var op = this.operator;
if (!rhs.has_side_effects(compressor)) return op == "in" && !is_object(rhs);
if (op == "&&" && rhs instanceof AST_PropAccess && lhs.equivalent_to(rhs.expression)) {
return rhs instanceof AST_Sub && rhs.property.has_side_effects(compressor);
}
return true;
});
def(AST_Block, function(compressor) {
return any(this.body, compressor);
@@ -7208,33 +7214,42 @@ merge(Compressor.prototype, {
return node;
});
def(AST_Binary, function(compressor, first_in_statement) {
if (this.operator == "in" && !is_object(this.right)) {
var left = this.left.drop_side_effect_free(compressor, first_in_statement);
if (left === this.left) return this;
var left = this.left;
var right = this.right;
var op = this.operator;
if (op == "in" && !is_object(right)) {
var lhs = left.drop_side_effect_free(compressor, first_in_statement);
if (lhs === left) return this;
var node = this.clone();
node.left = left || make_node(AST_Number, this.left, {
value: 0
});
node.left = lhs || make_node(AST_Number, left, { value: 0 });
return node;
}
var right = this.right.drop_side_effect_free(compressor, first_in_statement);
if (!right) return this.left.drop_side_effect_free(compressor, first_in_statement);
if (lazy_op[this.operator] && !(right instanceof AST_Function)) {
var rhs = right.drop_side_effect_free(compressor, first_in_statement);
if (!rhs) return left.drop_side_effect_free(compressor, first_in_statement);
if (lazy_op[op] && !(rhs instanceof AST_Function)) {
var node = this;
if (right !== node.right) {
node = this.clone();
node.right = right.drop_side_effect_free(compressor);
if (op == "&&"
&& rhs instanceof AST_PropAccess
&& left.equivalent_to(rhs.expression)
&& !left.has_side_effects(compressor)) {
var prop = rhs instanceof AST_Sub && rhs.property.drop_side_effect_free(compressor);
if (!prop) return left.drop_side_effect_free(compressor, first_in_statement);
node = node.clone();
node.right = prop;
} else if (rhs !== right) {
node = node.clone();
node.right = rhs.drop_side_effect_free(compressor);
}
if (this.operator == "??") return node;
if (op == "??") return node;
return (first_in_statement ? best_of_statement : best_of_expression)(node, make_node(AST_Binary, this, {
operator: node.operator == "&&" ? "||" : "&&",
left: node.left.negate(compressor, first_in_statement),
right: node.right
operator: op == "&&" ? "||" : "&&",
left: left.negate(compressor, first_in_statement),
right: node.right,
}));
} else {
var left = this.left.drop_side_effect_free(compressor, first_in_statement);
if (!left) return right;
return make_sequence(this, [ left, right.drop_side_effect_free(compressor) ]);
var lhs = left.drop_side_effect_free(compressor, first_in_statement);
if (!lhs) return rhs;
return make_sequence(this, [ lhs, rhs.drop_side_effect_free(compressor) ]);
}
});
def(AST_Call, function(compressor, first_in_statement) {