feat(minifier): typeof foo === 'number' => typeof foo == 'number' (…

…#8112)
oxc-project · Dec 25, 2024 · 2331ea8 · 2331ea8
1 parent e594c39
commit 2331ea8
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Showing 3 changed files with 53 additions and 11 deletions.
diff --git a/crates/oxc_minifier/src/ast_passes/peephole_substitute_alternate_syntax.rs b/crates/oxc_minifier/src/ast_passes/peephole_substitute_alternate_syntax.rs
@@ -86,6 +86,7 @@ impl<'a> Traverse<'a> for PeepholeSubstituteAlternateSyntax {
                 self.try_compress_arrow_expression(arrow_expr, ctx);
             }
             Expression::ChainExpression(e) => self.try_compress_chain_call_expression(e, ctx),
+            Expression::BinaryExpression(e) => self.try_compress_type_of_equal_string(e, ctx),
             _ => {}
         }
 
@@ -622,6 +623,30 @@ impl<'a, 'b> PeepholeSubstituteAlternateSyntax {
         }
     }
 
+    /// `typeof foo === 'number'` -> `typeof foo == 'number'`
+    fn try_compress_type_of_equal_string(
+        &mut self,
+        e: &mut BinaryExpression<'a>,
+        _ctx: Ctx<'a, 'b>,
+    ) {
+        let op = match e.operator {
+            BinaryOperator::StrictEquality => BinaryOperator::Equality,
+            BinaryOperator::StrictInequality => BinaryOperator::Inequality,
+            _ => return,
+        };
+        if Self::commutative_pair(
+            (&e.left, &e.right),
+            |a| a.is_string_literal().then_some(()),
+            |b| matches!(b, Expression::UnaryExpression(e) if e.operator.is_typeof()).then_some(()),
+        )
+        .is_none()
+        {
+            return;
+        }
+        e.operator = op;
+        self.changed = true;
+    }
+
     fn try_compress_chain_call_expression(
         &mut self,
         chain_expr: &mut ChainExpression<'a>,
@@ -1100,4 +1125,16 @@ mod test {
         test("foo !== 1 || foo !== void 0 && foo !== null", "foo !== 1 || foo != null");
         test_same("foo !== void 0 && bar !== null");
     }
+
+    #[test]
+    fn test_try_compress_type_of_equal_string() {
+        test("typeof foo === 'number'", "typeof foo == 'number'");
+        test("'number' === typeof foo", "'number' == typeof foo");
+        test("typeof foo === `number`", "typeof foo == 'number'");
+        test("`number` === typeof foo", "'number' == typeof foo");
+        test("typeof foo !== 'number'", "typeof foo != 'number'");
+        test("'number' !== typeof foo", "'number' != typeof foo");
+        test("typeof foo !== `number`", "typeof foo != 'number'");
+        test("`number` !== typeof foo", "'number' != typeof foo");
+    }
 }
diff --git a/crates/oxc_syntax/src/operator.rs b/crates/oxc_syntax/src/operator.rs
@@ -488,6 +488,11 @@ impl UnaryOperator {
         self == Self::BitwiseNot
     }
 
+    /// Returns `true` if this is the [`void`](UnaryOperator::Typeof) operator.
+    pub fn is_typeof(self) -> bool {
+        self == Self::Typeof
+    }
+
     /// Returns `true` if this is the [`void`](UnaryOperator::Void) operator.
     pub fn is_void(self) -> bool {
         self == Self::Void

diff --git a/tasks/minsize/minsize.snap b/tasks/minsize/minsize.snap
@@ -1,27 +1,27 @@
            | Oxc        | ESBuild    | Oxc        | ESBuild    |
 Original   | minified   | minified   | gzip       | gzip       | Fixture
 -------------------------------------------------------------------------------------
-72.14 kB   | 24.00 kB   | 23.70 kB   | 8.58 kB    | 8.54 kB    | react.development.js
+72.14 kB   | 23.96 kB   | 23.70 kB   | 8.58 kB    | 8.54 kB    | react.development.js
 
-173.90 kB  | 61.55 kB   | 59.82 kB   | 19.54 kB   | 19.33 kB   | moment.js 
+173.90 kB  | 61.52 kB   | 59.82 kB   | 19.54 kB   | 19.33 kB   | moment.js 
 
-287.63 kB  | 92.59 kB   | 90.07 kB   | 32.28 kB   | 31.95 kB   | jquery.js 
+287.63 kB  | 92.51 kB   | 90.07 kB   | 32.29 kB   | 31.95 kB   | jquery.js 
 
-342.15 kB  | 121.55 kB  | 118.14 kB  | 44.64 kB   | 44.37 kB   | vue.js    
+342.15 kB  | 121.48 kB  | 118.14 kB  | 44.65 kB   | 44.37 kB   | vue.js    
 
 544.10 kB  | 73.32 kB   | 72.48 kB   | 26.13 kB   | 26.20 kB   | lodash.js 
 
-555.77 kB  | 276.01 kB  | 270.13 kB  | 91.13 kB   | 90.80 kB   | d3.js     
+555.77 kB  | 275.83 kB  | 270.13 kB  | 91.13 kB   | 90.80 kB   | d3.js     
 
-1.01 MB    | 466.62 kB  | 458.89 kB  | 126.69 kB  | 126.71 kB  | bundle.min.js
+1.01 MB    | 466.57 kB  | 458.89 kB  | 126.69 kB  | 126.71 kB  | bundle.min.js
 
-1.25 MB    | 661.47 kB  | 646.76 kB  | 163.94 kB  | 163.73 kB  | three.js  
+1.25 MB    | 661.44 kB  | 646.76 kB  | 163.95 kB  | 163.73 kB  | three.js  
 
-2.14 MB    | 740.43 kB  | 724.14 kB  | 181.34 kB  | 181.07 kB  | victory.js
+2.14 MB    | 740.15 kB  | 724.14 kB  | 181.34 kB  | 181.07 kB  | victory.js
 
-3.20 MB    | 1.02 MB    | 1.01 MB    | 332.00 kB  | 331.56 kB  | echarts.js
+3.20 MB    | 1.02 MB    | 1.01 MB    | 332.02 kB  | 331.56 kB  | echarts.js
 
-6.69 MB    | 2.39 MB    | 2.31 MB    | 495.62 kB  | 488.28 kB  | antd.js   
+6.69 MB    | 2.39 MB    | 2.31 MB    | 495.64 kB  | 488.28 kB  | antd.js   
 
-10.95 MB   | 3.54 MB    | 3.49 MB    | 909.73 kB  | 915.50 kB  | typescript.js
+10.95 MB   | 3.54 MB    | 3.49 MB    | 909.75 kB  | 915.50 kB  | typescript.js