Optimize conditionals where the consequent and alternative are both booleans and not equivalent

2014-09-13 18:59:19 +03:00
parent 189dbf02b6
commit a1a4c2ada7
2 changed files with 68 additions and 0 deletions
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -2386,6 +2386,20 @@ merge(Compressor.prototype, {

            }
        }
+        // x=y?true:false --> x=!!y
+        if (consequent instanceof AST_True
+            && alternative instanceof AST_False) {
+            self.condition = self.condition.negate(compressor);
+            return make_node(AST_UnaryPrefix, self.condition, {
+                operator: "!",
+                expression: self.condition
+            });
+        }
+        // x=y?false:true --> x=!y
+        if (consequent instanceof AST_False
+            && alternative instanceof AST_True) {
+            return self.condition.negate(compressor)
+        }
        return self;
    });