feat(minifier): try collapse conditional to logical or expr (#8197)

This commit is contained in:
Cameron 2024-12-31 07:59:08 +00:00 committed by GitHub
parent 3eaff2a51c
commit bf266e13b0
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
2 changed files with 33 additions and 11 deletions

View file

@ -57,6 +57,9 @@ impl<'a> Traverse<'a> for PeepholeMinimizeConditions {
fn exit_expression(&mut self, expr: &mut Expression<'a>, ctx: &mut TraverseCtx<'a>) {
if let Some(folded_expr) = match expr {
Expression::UnaryExpression(e) => Self::try_minimize_not(e, ctx),
Expression::ConditionalExpression(conditional_expr) => {
Self::try_minimize_conditional(conditional_expr, ctx)
}
_ => None,
} {
*expr = folded_expr;
@ -253,6 +256,28 @@ impl<'a> PeepholeMinimizeConditions {
None => ctx.ast.void_0(return_stmt.span),
}
}
/// `a ? a : b` -> `a || b`
fn try_minimize_conditional(
expr: &mut ConditionalExpression<'a>,
ctx: &mut TraverseCtx<'a>,
) -> Option<Expression<'a>> {
let Expression::Identifier(test_ident) = &expr.test else { return None };
let Expression::Identifier(consequent_ident) = &expr.consequent else { return None };
if test_ident.name != consequent_ident.name {
return None;
}
let ident = ctx.ast.move_expression(&mut expr.test);
Some(ctx.ast.expression_logical(
expr.span,
ident,
LogicalOperator::Or,
ctx.ast.move_expression(&mut expr.alternate),
))
}
}
/// <https://github.com/google/closure-compiler/blob/v20240609/test/com/google/javascript/jscomp/PeepholeMinimizeConditionsTest.java>
@ -662,21 +687,18 @@ mod test {
}
#[test]
#[ignore]
fn test_minimize_hook() {
fold("x ? x : y", "x || y");
// We assume GETPROPs don't have side effects.
fold("x.y ? x.y : x.z", "x.y || x.z");
fold("x?.y ? x?.y : x.z", "x?.y || x.z");
fold("x?.y ? x?.y : x?.z", "x?.y || x?.z");
fold_same("x.y ? x.y : x.z");
fold_same("x?.y ? x?.y : x.z");
fold_same("x?.y ? x?.y : x?.z");
// This can be folded if x() does not have side effects.
fold_same("x() ? x() : y()");
fold_same("x?.() ? x?.() : y()");
fold("!x ? foo() : bar()", "x ? bar() : foo()");
fold("while(!(x ? y : z)) foo();", "while(x ? !y : !z) foo();");
fold("(x ? !y : !z) ? foo() : bar()", "(x ? y : z) ? bar() : foo()");
// fold("!x ? foo() : bar()", "x ? bar() : foo()");
// fold("while(!(x ? y : z)) foo();", "while(x ? !y : !z) foo();");
// fold("(x ? !y : !z) ? foo() : bar()", "(x ? y : z) ? bar() : foo()");
}
#[test]

View file

@ -21,7 +21,7 @@ Original | minified | minified | gzip | gzip | Fixture
3.20 MB | 1.01 MB | 1.01 MB | 332.21 kB | 331.56 kB | echarts.js
6.69 MB | 2.32 MB | 2.31 MB | 493.08 kB | 488.28 kB | antd.js
6.69 MB | 2.32 MB | 2.31 MB | 493.07 kB | 488.28 kB | antd.js
10.95 MB | 3.51 MB | 3.49 MB | 910.42 kB | 915.50 kB | typescript.js
10.95 MB | 3.51 MB | 3.49 MB | 910.37 kB | 915.50 kB | typescript.js