feat(minifier): minimize ~undefined, ~null, ~true, ~false (#8247

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oxc-project · Jan 4, 2025 · bd8d677 · bd8d677
1 parent f73dc9e
commit bd8d677
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diff --git a/crates/oxc_ecmascript/src/constant_evaluation/mod.rs b/crates/oxc_ecmascript/src/constant_evaluation/mod.rs
@@ -440,6 +440,10 @@ pub trait ConstantEvaluation<'a> {
                         .map(|v| !v.to_int_32())
                         .map(|v| v as f64)
                         .map(ConstantValue::Number),
+                    ValueType::Undefined | ValueType::Null => Some(ConstantValue::Number(-1.0)),
+                    ValueType::Boolean => self
+                        .get_side_free_boolean_value(&expr.argument)
+                        .map(|v| ConstantValue::Number(if v { -2.0 } else { -1.0 })),
                     _ => None,
                 }
             }

diff --git a/crates/oxc_minifier/src/ast_passes/peephole_fold_constants.rs b/crates/oxc_minifier/src/ast_passes/peephole_fold_constants.rs
@@ -1447,6 +1447,14 @@ mod test {
         test("y | 3 & 7", "y | 3");
     }
 
+    #[test]
+    fn test_fold_bitwise_not() {
+        test("~undefined", "-1");
+        test("~null", "-1");
+        test("~false", "-1");
+        test("~true", "-2");
+    }
+
     #[test]
     fn test_fold_bit_shifts() {
         test("x = 1 << 0", "x=1");