feat(minifier): improve minimizing unary not expressions

oxc-project · Jan 5, 2025 · 0e5b5ec · 0e5b5ec
1 parent a580c32
commit 0e5b5ec
Show file tree

Hide file tree

Showing 2 changed files with 43 additions and 34 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
@@ -85,13 +85,20 @@ impl<'a> PeepholeMinimizeConditions {
         }
         if let Expression::UnaryExpression(e1) = &mut expr.argument {
             if e1.operator.is_not() {
+                // `!!!a` -> `!!a`
                 if let Expression::UnaryExpression(e2) = &mut e1.argument {
                     if e2.operator.is_not() {
                         expr.argument = ctx.ast.move_expression(&mut e2.argument);
+                        return Some(ctx.ast.move_expression(&mut expr.argument));
                     }
                 }
+                // `!!a` -> `a` // ONLY in boolean contexts
+                if Self::is_in_boolean_context(ctx) {
+                    return Some(ctx.ast.move_expression(&mut e1.argument));
+                }
             }
         }
+
         let Expression::BinaryExpression(binary_expr) = &mut expr.argument else { return None };
         let new_op = binary_expr.operator.equality_inverse_operator()?;
         binary_expr.operator = new_op;
@@ -386,10 +393,6 @@ impl<'a> PeepholeMinimizeConditions {
                 }
                 (true, false) => {
                     let ident = ctx.ast.move_expression(&mut expr.test);
-
-                    if Self::is_in_boolean_context(ctx) {
-                        return Some(ident);
-                    }
                     return Some(ctx.ast.expression_unary(
                         expr.span,
                         UnaryOperator::LogicalNot,
@@ -409,15 +412,11 @@ impl<'a> PeepholeMinimizeConditions {
                 let ident = ctx.ast.move_expression(&mut expr.test);
                 return Some(ctx.ast.expression_logical(
                     expr.span,
-                    if Self::is_in_boolean_context(ctx) {
-                        ident
-                    } else {
-                        ctx.ast.expression_unary(
-                            SPAN,
-                            UnaryOperator::LogicalNot,
-                            ctx.ast.expression_unary(SPAN, UnaryOperator::LogicalNot, ident),
-                        )
-                    },
+                    ctx.ast.expression_unary(
+                        SPAN,
+                        UnaryOperator::LogicalNot,
+                        ctx.ast.expression_unary(SPAN, UnaryOperator::LogicalNot, ident),
+                    ),
                     LogicalOperator::Or,
                     ctx.ast.move_expression(&mut expr.alternate),
                 ));
@@ -448,15 +447,11 @@ impl<'a> PeepholeMinimizeConditions {
             let ident = ctx.ast.move_expression(&mut expr.test);
             return Some(ctx.ast.expression_logical(
                 expr.span,
-                if Self::is_in_boolean_context(ctx) {
-                    ident
-                } else {
-                    ctx.ast.expression_unary(
-                        SPAN,
-                        UnaryOperator::LogicalNot,
-                        ctx.ast.expression_unary(SPAN, UnaryOperator::LogicalNot, ident),
-                    )
-                },
+                ctx.ast.expression_unary(
+                    SPAN,
+                    UnaryOperator::LogicalNot,
+                    ctx.ast.expression_unary(SPAN, UnaryOperator::LogicalNot, ident),
+                ),
                 LogicalOperator::And,
                 ctx.ast.move_expression(&mut expr.consequent),
             ));
@@ -851,10 +846,10 @@ mod test {
 
     #[test]
     fn test_minimize_expr_condition() {
-        fold("(x ? true : false) && y()", "x && y()");
+        fold("(x ? true : false) && y()", "!!x && y()");
         fold("(x ? false : true) && y()", "!x && y()");
-        fold("(x ? true : y) && y()", "(x || y) && y()");
-        fold("(x ? y : false) && y()", "(x && y) && y()");
+        fold("(x ? true : y) && y()", "(!!x || y) && y()");
+        fold("(x ? y : false) && y()", "(!!x && y) && y()");
         fold("var x; (x && true) && y()", "var x; x && y()");
         fold("var x; (x && false) && y()", "var x; false && y()");
         fold("(x && true) && y()", "x && y()");
@@ -1688,4 +1683,18 @@ mod test {
         test("delete x !== false", "delete x");
         test("delete x != false", "delete x");
     }
+
+    #[test]
+    fn minimize_duplicate_nots() {
+        test("!!x", "x");
+        test("!!!x", "!x");
+        test("!!!!x", "x");
+        test("!!!(x && y)", "!(x && y)");
+        test_same("var k = () => { !!x; }");
+
+        test_same("var k = !!x;");
+        test_same("function k () { return !!x; }");
+        test_same("var k = () => { return !!x; }");
+        test_same("var k = () => !!x;");
+    }
 }
diff --git a/tasks/minsize/minsize.snap b/tasks/minsize/minsize.snap
@@ -5,23 +5,23 @@ Original   | minified   | minified   | gzip       | gzip       | Fixture
 
 173.90 kB  | 59.87 kB   | 59.82 kB   | 19.43 kB   | 19.33 kB   | moment.js 
 
-287.63 kB  | 90.19 kB   | 90.07 kB   | 32.10 kB   | 31.95 kB   | jquery.js 
+287.63 kB  | 90.18 kB   | 90.07 kB   | 32.10 kB   | 31.95 kB   | jquery.js 
 
-342.15 kB  | 118.25 kB  | 118.14 kB  | 44.53 kB   | 44.37 kB   | vue.js    
+342.15 kB  | 118.23 kB  | 118.14 kB  | 44.52 kB   | 44.37 kB   | vue.js    
 
-544.10 kB  | 71.82 kB   | 72.48 kB   | 26.20 kB   | 26.20 kB   | lodash.js 
+544.10 kB  | 71.80 kB   | 72.48 kB   | 26.18 kB   | 26.20 kB   | lodash.js 
 
-555.77 kB  | 273.19 kB  | 270.13 kB  | 90.98 kB   | 90.80 kB   | d3.js     
+555.77 kB  | 273.17 kB  | 270.13 kB  | 90.96 kB   | 90.80 kB   | d3.js     
 
-1.01 MB    | 460.34 kB  | 458.89 kB  | 126.86 kB  | 126.71 kB  | bundle.min.js
+1.01 MB    | 460.34 kB  | 458.89 kB  | 126.85 kB  | 126.71 kB  | bundle.min.js
 
 1.25 MB    | 652.70 kB  | 646.76 kB  | 163.54 kB  | 163.73 kB  | three.js  
 
-2.14 MB    | 726.21 kB  | 724.14 kB  | 180.20 kB  | 181.07 kB  | victory.js
+2.14 MB    | 726.18 kB  | 724.14 kB  | 180.17 kB  | 181.07 kB  | victory.js
 
-3.20 MB    | 1.01 MB    | 1.01 MB    | 331.90 kB  | 331.56 kB  | echarts.js
+3.20 MB    | 1.01 MB    | 1.01 MB    | 331.88 kB  | 331.56 kB  | echarts.js
 
-6.69 MB    | 2.32 MB    | 2.31 MB    | 492.87 kB  | 488.28 kB  | antd.js   
+6.69 MB    | 2.32 MB    | 2.31 MB    | 492.84 kB  | 488.28 kB  | antd.js   
 
-10.95 MB   | 3.50 MB    | 3.49 MB    | 909.30 kB  | 915.50 kB  | typescript.js
+10.95 MB   | 3.50 MB    | 3.49 MB    | 909.21 kB  | 915.50 kB  | typescript.js