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graphite-app merged 1 commit into from
Aug 16, 2025
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feat(minifier): mark more known global methods as side-effect free #13086

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106 changes: 85 additions & 21 deletions crates/oxc_ecmascript/src/side_effects/may_have_side_effects.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -242,6 +242,36 @@ impl<'a> MayHaveSideEffects<'a> for BinaryExpression<'a> {
}
}

fn is_pure_regexp(name: &str, args: &[Argument<'_>]) -> bool {
name == "RegExp"
&& match args.len() {
0 | 1 => true,
2 => args[1].as_expression().is_some_and(|e| {
matches!(e, Expression::Identifier(_) | Expression::StringLiteral(_))
}),
_ => false,
}
}

#[rustfmt::skip]
fn is_pure_global_function(name: &str) -> bool {
matches!(name, "decodeURI" | "decodeURIComponent" | "encodeURI" | "encodeURIComponent"
| "escape" | "isFinite" | "isNaN" | "parseFloat" | "parseInt")
}

#[rustfmt::skip]
fn is_pure_call(name: &str) -> bool {
matches!(name, "Date" | "Boolean" | "Error" | "EvalError" | "RangeError" | "ReferenceError"
| "SyntaxError" | "TypeError" | "URIError" | "Number" | "Object" | "String" | "Symbol")
}

#[rustfmt::skip]
fn is_pure_constructor(name: &str) -> bool {
matches!(name, "Set" | "Map" | "WeakSet" | "WeakMap" | "ArrayBuffer" | "Date"
| "Boolean" | "Error" | "EvalError" | "RangeError" | "ReferenceError"
| "SyntaxError" | "TypeError" | "URIError" | "Number" | "Object" | "String" | "Symbol")
}

/// Whether the name matches any known global constructors.
///
/// <https://tc39.es/ecma262/multipage/global-object.html#sec-constructor-properties-of-the-global-object>
Expand Down Expand Up @@ -530,43 +560,77 @@ fn get_array_minimum_length(arr: &ArrayExpression) -> usize {
.sum()
}

// `PF` in <https://github.com/rollup/rollup/blob/master/src/ast/nodes/shared/knownGlobals.ts>
impl<'a> MayHaveSideEffects<'a> for CallExpression<'a> {
fn may_have_side_effects(&self, ctx: &impl MayHaveSideEffectsContext<'a>) -> bool {
if (self.pure && ctx.annotations()) || ctx.manual_pure_functions(&self.callee) {
return self.arguments.iter().any(|e| e.may_have_side_effects(ctx));
}

if let Expression::Identifier(ident) = &self.callee
&& ctx.is_global_reference(ident)
&& let name = ident.name.as_str()
&& (is_pure_global_function(name)
|| is_pure_call(name)
|| is_pure_regexp(name, &self.arguments))
{
return self.arguments.iter().any(|e| e.may_have_side_effects(ctx));
}

let (ident, name) = match &self.callee {
Expression::StaticMemberExpression(member) if !member.optional => {
(member.object.get_identifier_reference(), member.property.name.as_str())
}
Expression::ComputedMemberExpression(member) if !member.optional => {
match &member.expression {
Expression::StringLiteral(s) => {
(member.object.get_identifier_reference(), s.value.as_str())
}
_ => return true,
}
}
_ => return true,
};

let Some(object) = ident.map(|ident| ident.name.as_str()) else { return true };

#[rustfmt::skip]
let is_global = match object {
"Array" => matches!(name, "isArray" | "of"),
"ArrayBuffer" => name == "isView",
"Date" => matches!(name, "now" | "parse" | "UTC"),
"Math" => matches!(name, "abs" | "acos" | "acosh" | "asin" | "asinh" | "atan" | "atan2" | "atanh"
| "cbrt" | "ceil" | "clz32" | "cos" | "cosh" | "exp" | "expm1" | "floor" | "fround" | "hypot"
| "imul" | "log" | "log10" | "log1p" | "log2" | "max" | "min" | "pow" | "random" | "round"
| "sign" | "sin" | "sinh" | "sqrt" | "tan" | "tanh" | "trunc"),
"Number" => matches!(name, "isFinite" | "isInteger" | "isNaN" | "isSafeInteger" | "parseFloat" | "parseInt"),
"Object" => matches!(name, "create" | "getOwnPropertyDescriptor" | "getOwnPropertyDescriptors" | "getOwnPropertyNames"
| "getOwnPropertySymbols" | "getPrototypeOf" | "hasOwn" | "is" | "isExtensible" | "isFrozen" | "isSealed" | "keys"),
"String" => matches!(name, "fromCharCode" | "fromCodePoint" | "raw"),
"Symbol" => matches!(name, "for" | "keyFor"),
"URL" => name == "canParse",
"Float32Array" | "Float64Array" | "Int16Array" | "Int32Array" | "Int8Array" | "Uint16Array" | "Uint32Array" | "Uint8Array" | "Uint8ClampedArray" => name == "of",
_ => false,
};

if is_global {
return self.arguments.iter().any(|e| e.may_have_side_effects(ctx));
}

true
}
}

// `[ValueProperties]: PURE` in <https://github.com/rollup/rollup/blob/master/src/ast/nodes/shared/knownGlobals.ts>
impl<'a> MayHaveSideEffects<'a> for NewExpression<'a> {
fn may_have_side_effects(&self, ctx: &impl MayHaveSideEffectsContext<'a>) -> bool {
if (self.pure && ctx.annotations()) || ctx.manual_pure_functions(&self.callee) {
return self.arguments.iter().any(|e| e.may_have_side_effects(ctx));
}
if let Expression::Identifier(ident) = &self.callee
&& ctx.is_global_reference(ident)
&& matches!(
ident.name.as_str(),
"Set"
| "Map"
| "WeakSet"
| "WeakMap"
| "ArrayBuffer"
| "Date"
| "Boolean"
| "Error"
| "EvalError"
| "RangeError"
| "ReferenceError"
| "RegExp"
| "SyntaxError"
| "TypeError"
| "URIError"
| "Number"
| "Object"
| "String"
)
&& let name = ident.name.as_str()
&& (is_pure_constructor(name) || is_pure_regexp(name, &self.arguments))
{
return self.arguments.iter().any(|e| e.may_have_side_effects(ctx));
}
Expand Down
2 changes: 1 addition & 1 deletion crates/oxc_minifier/src/peephole/remove_unused_expression.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -577,7 +577,7 @@ impl<'a> PeepholeOptimizations {
}
}

false
!call_expr.may_have_side_effects(ctx)
}

fn fold_arguments_into_needed_expressions(
Expand Down
26 changes: 13 additions & 13 deletions crates/oxc_minifier/src/peephole/replace_known_methods.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -1431,7 +1431,7 @@ mod test {
test("x = String.fromCharCode(0)", "x = '\\0'");
test("x = String.fromCharCode(120)", "x = 'x'");
test("x = String.fromCharCode(120, 121)", "x = 'xy'");
test_same("String.fromCharCode(55358, 56768)");
test_same("x = String.fromCharCode(55358, 56768)");
test("x = String.fromCharCode(0x10000)", "x = '\\0'");
test("x = String.fromCharCode(0x10078, 0x10079)", "x = 'xy'");
test("x = String.fromCharCode(0x1_0000_FFFF)", "x = '\u{ffff}'");
Expand Down Expand Up @@ -1635,8 +1635,8 @@ mod test {
test("x = encodeURI('café')", "x = 'caf%C3%A9'"); // spellchecker:disable-line
test("x = encodeURI('测试')", "x = '%E6%B5%8B%E8%AF%95'");

test_same("encodeURI('a', 'b')");
test_same("encodeURI(x)");
test_same("x = encodeURI('a', 'b')");
test_same("x = encodeURI(x)");
}

#[test]
Expand All @@ -1654,8 +1654,8 @@ mod test {
test("x = encodeURIComponent('café')", "x = 'caf%C3%A9'"); // spellchecker:disable-line
test("x = encodeURIComponent('测试')", "x = '%E6%B5%8B%E8%AF%95'");

test_same("encodeURIComponent('a', 'b')");
test_same("encodeURIComponent(x)");
test_same("x = encodeURIComponent('a', 'b')");
test_same("x = encodeURIComponent(x)");
}

#[test]
Expand All @@ -1675,11 +1675,11 @@ mod test {
test("x = decodeURI('caf%C3%A9')", "x = 'café'"); // spellchecker:disable-line
test("x = decodeURI('%E6%B5%8B%E8%AF%95')", "x = '测试'");

test_same("decodeURI('%ZZ')"); // URIError
test_same("decodeURI('%A')"); // URIError
test_same("x = decodeURI('%ZZ')"); // URIError
test_same("x = decodeURI('%A')"); // URIError

test_same("decodeURI('a', 'b')");
test_same("decodeURI(x)");
test_same("x = decodeURI('a', 'b')");
test_same("x = decodeURI(x)");
}

#[test]
Expand All @@ -1698,11 +1698,11 @@ mod test {
test("x = decodeURIComponent('caf%C3%A9')", "x = 'café'"); // spellchecker:disable-line
test("x = decodeURIComponent('%E6%B5%8B%E8%AF%95')", "x = '测试'");

test_same("decodeURIComponent('%ZZ')"); // URIError
test_same("decodeURIComponent('%A')"); // URIError
test_same("x = decodeURIComponent('%ZZ')"); // URIError
test_same("x = decodeURIComponent('%A')"); // URIError

test_same("decodeURIComponent('a', 'b')");
test_same("decodeURIComponent(x)");
test_same("x = decodeURIComponent('a', 'b')");
test_same("x = decodeURIComponent(x)");
}

#[test]
Expand Down
2 changes: 1 addition & 1 deletion crates/oxc_minifier/src/peephole/substitute_alternate_syntax.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -1699,7 +1699,7 @@ mod test {
test("new RegExp('a')", "");
test("new RegExp(0)", "");
test("new RegExp(null)", "");
test("new RegExp('a', 'g')", "RegExp('a', 'g')");
test("x = new RegExp('a', 'g')", "x = RegExp('a', 'g')");
test_same("new RegExp(foo)");
test("new RegExp(/foo/)", "");
}
Expand Down
129 changes: 126 additions & 3 deletions crates/oxc_minifier/tests/ecmascript/may_have_side_effects.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -180,7 +180,8 @@ fn closure_compiler_tests() {
test("templateFunction`template`", true);
test("st = `${name}template`", true);
test("tempFunc = templateFunction`template`", true);
// test("new RegExp('foobar', 'i')", false);
test("new RegExp('foobar', 'i')", false);
test("new RegExp('foobar', 2)", true);
test("new RegExp(SomethingWacky(), 'i')", true);
// test("new Array()", false);
// test("new Array", false);
Expand All @@ -205,8 +206,8 @@ fn closure_compiler_tests() {
// test("(true ? {} : []).foo = 2;", false);
// test("({},[]).foo = 2;", false);
test("delete a.b", true);
// test("Math.random();", false);
test("Math.random(seed);", true);
test("Math.random();", false);
test("Math.random(Math);", true);
// test("[1, 1].foo;", false);
// test("export var x = 0;", true);
// test("export let x = 0;", true);
Expand Down Expand Up @@ -751,6 +752,7 @@ fn test_property_access() {
test("[...a, 1][0]", true); // "...a" may have a sideeffect
}

// `[ValueProperties]: PURE` in <https://github.com/rollup/rollup/blob/master/src/ast/nodes/shared/knownGlobals.ts>
#[test]
fn test_new_expressions() {
test("new AggregateError", true);
Expand All @@ -773,6 +775,127 @@ fn test_new_expressions() {
test("new Number", false);
test("new Object", false);
test("new String", false);
test("new Symbol", false);
}

// `PF` in <https://github.com/rollup/rollup/blob/master/src/ast/nodes/shared/knownGlobals.ts>
#[test]
fn test_call_expressions() {
test("AggregateError()", true);
test("DataView()", true);
test("Set()", true);
test("Map()", true);
test("WeakSet()", true);
test("WeakMap()", true);
test("ArrayBuffer()", true);
test("Date()", false);
test("Boolean()", false);
test("Error()", false);
test("EvalError()", false);
test("RangeError()", false);
test("ReferenceError()", false);
test("RegExp()", false);
test("SyntaxError()", false);
test("TypeError()", false);
test("URIError()", false);
test("Number()", false);
test("Object()", false);
test("String()", false);
test("Symbol()", false);

test("decodeURI()", false);
test("decodeURIComponent()", false);
test("encodeURI()", false);
test("encodeURIComponent()", false);
test("escape()", false);
test("isFinite()", false);
test("isNaN()", false);
test("parseFloat()", false);
test("parseInt()", false);

test("Array.isArray()", false);
test("Array.of()", false);

test("ArrayBuffer.isView()", false);

test("Date.now()", false);
test("Date.parse()", false);
test("Date.UTC()", false);

test("Math.abs()", false);
test("Math.acos()", false);
test("Math.acosh()", false);
test("Math.asin()", false);
test("Math.asinh()", false);
test("Math.atan()", false);
test("Math.atan2()", false);
test("Math.atanh()", false);
test("Math.cbrt()", false);
test("Math.ceil()", false);
test("Math.clz32()", false);
test("Math.cos()", false);
test("Math.cosh()", false);
test("Math.exp()", false);
test("Math.expm1()", false);
test("Math.floor()", false);
test("Math.fround()", false);
test("Math.hypot()", false);
test("Math.imul()", false);
test("Math.log()", false);
test("Math.log10()", false);
test("Math.log1p()", false);
test("Math.log2()", false);
test("Math.max()", false);
test("Math.min()", false);
test("Math.pow()", false);
test("Math.random()", false);
test("Math.round()", false);
test("Math.sign()", false);
test("Math.sin()", false);
test("Math.sinh()", false);
test("Math.sqrt()", false);
test("Math.tan()", false);
test("Math.tanh()", false);
test("Math.trunc()", false);

test("Number.isFinite()", false);
test("Number.isInteger()", false);
test("Number.isNaN()", false);
test("Number.isSafeInteger()", false);
test("Number.parseFloat()", false);
test("Number.parseInt()", false);

test("Object.create()", false);
test("Object.getOwnPropertyDescriptor()", false);
test("Object.getOwnPropertyDescriptors()", false);
test("Object.getOwnPropertyNames()", false);
test("Object.getOwnPropertySymbols()", false);
test("Object.getPrototypeOf()", false);
test("Object.hasOwn()", false);
test("Object.is()", false);
test("Object.isExtensible()", false);
test("Object.isFrozen()", false);
test("Object.isSealed()", false);
test("Object.keys()", false);

test("String.fromCharCode()", false);
test("String.fromCodePoint()", false);
test("String.raw()", false);

test("Symbol.for()", false);
test("Symbol.keyFor()", false);

test("URL.canParse()", false);

test("Float32Array.of()", false);
test("Float64Array.of()", false);
test("Int16Array.of()", false);
test("Int32Array.of()", false);
test("Int8Array.of()", false);
test("Uint16Array.of()", false);
test("Uint32Array.of()", false);
test("Uint8Array.of()", false);
test("Uint8ClampedArray.of()", false);
}

#[test]
Expand Down
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