feat(minifier): minimize (x = 1) === 1 -> (x = 1) == 1 (#8310)

oxc-project · Jan 7, 2025 · e3ff81e · e3ff81e
1 parent 4b68cc0
commit e3ff81e
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Showing 2 changed files with 31 additions and 9 deletions.
diff --git a/crates/oxc_minifier/src/ast_passes/peephole_minimize_conditions.rs b/crates/oxc_minifier/src/ast_passes/peephole_minimize_conditions.rs
@@ -541,8 +541,27 @@ impl<'a> PeepholeMinimizeConditions {
         e: &mut BinaryExpression<'a>,
         ctx: &mut TraverseCtx<'a>,
     ) -> Option<Expression<'a>> {
+        if !e.operator.is_equality() {
+            return None;
+        }
+        let left = ValueType::from(&e.left);
+        let right = ValueType::from(&e.right);
+        if left.is_undetermined() || right.is_undetermined() {
+            return None;
+        }
+        if left == right {
+            match e.operator {
+                BinaryOperator::StrictInequality => {
+                    e.operator = BinaryOperator::Inequality;
+                }
+                BinaryOperator::StrictEquality => {
+                    e.operator = BinaryOperator::Equality;
+                }
+                _ => {}
+            }
+        }
         match &mut e.right {
-            Expression::BooleanLiteral(b) if ValueType::from(&e.left).is_boolean() => {
+            Expression::BooleanLiteral(b) if left.is_boolean() => {
                 match e.operator {
                     BinaryOperator::Inequality | BinaryOperator::StrictInequality => {
                         e.operator = BinaryOperator::Equality;
@@ -562,9 +581,9 @@ impl<'a> PeepholeMinimizeConditions {
                 })
             }
             Expression::NumericLiteral(lit)
-                if lit.value == 0.0
+                if lit.value  == 0.0
                     && !e.left.is_literal() // let constant folding do the work
-                    && ValueType::from(&e.left).is_number()
+                    && left.is_number()
                     && Self::is_in_boolean_context(ctx) =>
             {
                 match e.operator {
@@ -1733,6 +1752,9 @@ mod test {
         test("if(x >> y !== 0){}", "if(x >> y){}");
         test("if((-0 != +0) !== false){}", "if (-0 != +0) {}");
         test_same("foo(x >> y == 0)");
+
+        test("(x = 1) === 1", "(x = 1) == 1");
+        test("(x = 1) !== 1", "(x = 1) != 1");
     }
 
     #[test]

diff --git a/tasks/minsize/minsize.snap b/tasks/minsize/minsize.snap
@@ -3,25 +3,25 @@ Original   | minified   | minified   | gzip       | gzip       | Fixture
 -------------------------------------------------------------------------------------
 72.14 kB   | 23.68 kB   | 23.70 kB   | 8.61 kB    | 8.54 kB    | react.development.js
 
-173.90 kB  | 59.87 kB   | 59.82 kB   | 19.43 kB   | 19.33 kB   | moment.js 
+173.90 kB  | 59.86 kB   | 59.82 kB   | 19.43 kB   | 19.33 kB   | moment.js 
 
 287.63 kB  | 90.15 kB   | 90.07 kB   | 32.07 kB   | 31.95 kB   | jquery.js 
 
-342.15 kB  | 118.22 kB  | 118.14 kB  | 44.52 kB   | 44.37 kB   | vue.js    
+342.15 kB  | 118.21 kB  | 118.14 kB  | 44.52 kB   | 44.37 kB   | vue.js    
 
 544.10 kB  | 71.79 kB   | 72.48 kB   | 26.18 kB   | 26.20 kB   | lodash.js 
 
-555.77 kB  | 273.15 kB  | 270.13 kB  | 90.95 kB   | 90.80 kB   | d3.js     
+555.77 kB  | 273.14 kB  | 270.13 kB  | 90.95 kB   | 90.80 kB   | d3.js     
 
 1.01 MB    | 460.31 kB  | 458.89 kB  | 126.84 kB  | 126.71 kB  | bundle.min.js
 
 1.25 MB    | 652.68 kB  | 646.76 kB  | 163.53 kB  | 163.73 kB  | three.js  
 
-2.14 MB    | 726.15 kB  | 724.14 kB  | 180.16 kB  | 181.07 kB  | victory.js
+2.14 MB    | 726.14 kB  | 724.14 kB  | 180.16 kB  | 181.07 kB  | victory.js
 
-3.20 MB    | 1.01 MB    | 1.01 MB    | 331.88 kB  | 331.56 kB  | echarts.js
+3.20 MB    | 1.01 MB    | 1.01 MB    | 331.89 kB  | 331.56 kB  | echarts.js
 
 6.69 MB    | 2.32 MB    | 2.31 MB    | 492.77 kB  | 488.28 kB  | antd.js   
 
-10.95 MB   | 3.50 MB    | 3.49 MB    | 909.11 kB  | 915.50 kB  | typescript.js
+10.95 MB   | 3.50 MB    | 3.49 MB    | 909.12 kB  | 915.50 kB  | typescript.js