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

account for side-effects in conditional call inversion

Browse Source 
fixes #2560
This commit is contained in:
alexlamsl 2017-12-07 21:55:29 +08:00
parent d21cb84696
commit 5d6f068455
2 changed files with 96 additions and 27 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

31
lib/compress.js
View File

@ -4652,18 +4652,20 @@ merge(Compressor.prototype, {
});
}
// x ? y(a) : y(b) --> y(x ? a : b)
var arg_index;
if (consequent instanceof AST_Call
&& alternative.TYPE === consequent.TYPE
&& consequent.args.length == 1
&& alternative.args.length == 1
&& consequent.expression.equivalent_to(alternative.expression)
&& !consequent.expression.has_side_effects(compressor)) {
consequent.args[0] = make_node(AST_Conditional, self, {
&& !self.condition.has_side_effects(compressor)
&& !consequent.expression.has_side_effects(compressor)
&& typeof (arg_index = single_arg_diff()) == "number") {
var node = consequent.clone();
node.args[arg_index] = make_node(AST_Conditional, self, {
condition: self.condition,
consequent: consequent.args[0],
alternative: alternative.args[0]
consequent: consequent.args[arg_index],
alternative: alternative.args[arg_index]
});
return consequent;
return node;
}
// x?y?z:a:a --> x&&y?z:a
if (consequent instanceof AST_Conditional
@ -4760,6 +4762,21 @@ merge(Compressor.prototype, {
&& node.expression instanceof AST_Constant
&& node.expression.getValue());
}
function single_arg_diff() {
var a = consequent.args;
var b = alternative.args;
var len = a.length;
if (len != b.length) return;
for (var i = 0; i < len; i++) {
if (!a[i].equivalent_to(b[i])) {
for (var j = i + 1; j < len; j++) {
if (!a[j].equivalent_to(b[j])) return;
}
return i;
}
}
}
});
OPT(AST_Boolean, function(self, compressor){

92
test/compress/conditionals.js
View File

@ -166,22 +166,24 @@ cond_1: {
conditionals: true
};
input: {
var do_something; // if undeclared it's assumed to have side-effects
if (some_condition()) {
do_something(x);
} else {
do_something(y);
}
if (some_condition()) {
side_effects(x);
} else {
side_effects(y);
function foo(do_something, some_condition) {
if (some_condition) {
do_something(x);
} else {
do_something(y);
}
if (some_condition) {
side_effects(x);
} else {
side_effects(y);
}
}
}
expect: {
var do_something;
do_something(some_condition() ? x : y);
some_condition() ? side_effects(x) : side_effects(y);
function foo(do_something, some_condition) {
do_something(some_condition ? x : y);
some_condition ? side_effects(x) : side_effects(y);
}
}
}
@ -190,16 +192,18 @@ cond_2: {
conditionals: true
};
input: {
var x, FooBar;
if (some_condition()) {
x = new FooBar(1);
} else {
x = new FooBar(2);
function foo(x, FooBar, some_condition) {
if (some_condition) {
x = new FooBar(1);
} else {
x = new FooBar(2);
}
}
}
expect: {
var x, FooBar;
x = new FooBar(some_condition() ? 1 : 2);
function foo(x, FooBar, some_condition) {
x = new FooBar(some_condition ? 1 : 2);
}
}
}
@ -1115,3 +1119,51 @@ issue_2535_2: {
"false",
]
}
issue_2560: {
options = {
conditionals: true,
inline: true,
reduce_funcs: true,
reduce_vars: true,
toplevel: true,
unused: true,
}
input: {
function log(x) {
console.log(x);
}
function foo() {
return log;
}
function bar() {
if (x !== (x = foo())) {
x(1);
} else {
x(2);
}
}
var x = function() {
console.log("init");
};
bar();
bar();
}
expect: {
function log(x) {
console.log(x);
}
function bar() {
x !== (x = log) ? x(1) : x(2);
}
var x = function() {
console.log("init");
};
bar();
bar();
}
expect_stdout: [
"1",
"2",
]
}