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enhance evaluate (#3549)
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@alexlamsl
alexlamsl authored Oct 29, 2019
1 parent 22a09ea commit 1d5c2be
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Showing 2 changed files with 127 additions and 22 deletions.
68 changes: 46 additions & 22 deletions lib/compress.js
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Original file line number Diff line number Diff line change
Expand Up @@ -3019,7 +3019,26 @@ merge(Compressor.prototype, {
});
def(AST_Call, function(compressor, cached, depth) {
var exp = this.expression;
if (compressor.option("unsafe") && exp instanceof AST_PropAccess) {
if (exp instanceof AST_SymbolRef) {
var fn = exp.fixed_value();
if (!(fn instanceof AST_Lambda)) return this;
if (fn.name && fn.name.definition().recursive_refs > 0) return this;
if (fn.body.length != 1 || !fn.is_constant_expression()) return this;
var stat = fn.body[0];
if (!(stat instanceof AST_Return)) return this;
var args = eval_args(this.args);
if (!args) return this;
fn.argnames.forEach(function(sym, i) {
var value = args[i];
sym.definition().references.forEach(function(node) {
node._eval = function() {
return value;
};
cached.push(node);
});
});
return stat.value ? stat.value._eval(compressor, cached, depth) : undefined;
} else if (compressor.option("unsafe") && exp instanceof AST_PropAccess) {
var key = exp.property;
if (key instanceof AST_Node) {
key = key._eval(compressor, cached, depth);
Expand All @@ -3037,13 +3056,8 @@ merge(Compressor.prototype, {
var native_fn = native_fns[val.constructor.name];
if (!native_fn || !native_fn[key]) return this;
}
var args = [];
for (var i = 0; i < this.args.length; i++) {
var arg = this.args[i];
var value = arg._eval(compressor, cached, depth);
if (arg === value) return this;
args.push(value);
}
var args = eval_args(this.args);
if (!args) return this;
if (key == "replace" && typeof args[1] == "function") return this;
try {
return val[key].apply(val, args);
Expand All @@ -3057,6 +3071,17 @@ merge(Compressor.prototype, {
}
}
return this;

function eval_args(args) {
var values = [];
for (var i = 0; i < args.length; i++) {
var arg = args[i];
var value = arg._eval(compressor, cached, depth);
if (arg === value) return;
values.push(value);
}
return values;
}
});
def(AST_New, return_this);
})(function(node, func) {
Expand Down Expand Up @@ -3406,19 +3431,19 @@ merge(Compressor.prototype, {
def(AST_Lambda, function(scope) {
var self = this;
var result = true;
var inner_scopes = [];
var scopes = [];
self.walk(new TreeWalker(function(node, descend) {
if (!result) return true;
if (node instanceof AST_Catch) {
inner_scopes.push(node.argname.scope);
scopes.push(node.argname.scope);
descend();
inner_scopes.pop();
scopes.pop();
return true;
}
if (node instanceof AST_Scope && node !== self) {
inner_scopes.push(node);
if (node instanceof AST_Scope) {
scopes.push(node);
descend();
inner_scopes.pop();
scopes.pop();
return true;
}
if (node instanceof AST_SymbolRef) {
Expand All @@ -3427,16 +3452,15 @@ merge(Compressor.prototype, {
return true;
}
var def = node.definition();
if (!self.variables.has(def.name) && !member(def.scope, inner_scopes)) {
if (scope) {
var scope_def = scope.find_variable(node);
if (def.undeclared ? !scope_def : scope_def === def) {
result = "f";
return true;
}
if (member(def.scope, scopes)) return true;
if (scope) {
var scope_def = scope.find_variable(node);
if (def.undeclared ? !scope_def : scope_def === def) {
result = "f";
return true;
}
result = false;
}
result = false;
return true;
}
}));
Expand Down
81 changes: 81 additions & 0 deletions test/compress/evaluate.js
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1757,3 +1757,84 @@ issue_3387_2: {
}
expect_stdout: "NaN"
}

simple_function_1: {
options = {
evaluate: true,
reduce_vars: true,
toplevel: true,
unused: true,
}
input: {
function sum(a, b) {
return a + b;
}
console.log(sum(1, 2) * sum(3, 4));
}
expect: {
console.log(21);
}
expect_stdout: "21"
}

simple_function_2: {
options = {
evaluate: true,
reduce_vars: true,
toplevel: true,
unused: true,
}
input: {
var sum = function(a, b) {
return a + b;
}
console.log(sum(1, 2) * sum(3, 4));
}
expect: {
console.log(21);
}
expect_stdout: "21"
}

recursive_function_1: {
options = {
evaluate: true,
reduce_vars: true,
toplevel: true,
unused: true,
}
input: {
function factorial(a) {
return a > 0 ? a * factorial(a - 1) : 1;
}
console.log(factorial(5));
}
expect: {
console.log(function factorial(a) {
return a > 0 ? a * factorial(a - 1) : 1;
}(5));
}
expect_stdout: "120"
}

recursive_function_2: {
options = {
evaluate: true,
reduce_vars: true,
toplevel: true,
unused: true,
}
input: {
var factorial = function(a) {
return a > 0 ? a * factorial(a - 1) : 1;
}
console.log(factorial(5));
}
expect: {
var factorial = function(a) {
return a > 0 ? a * factorial(a - 1) : 1;
}
console.log(factorial(5));
}
expect_stdout: "120"
}

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