From af917b1e4d719f25d04e5443e676779afd5f5ce5 Mon Sep 17 00:00:00 2001
From: Futago-za Ryuu <futagoza.ryuu@gmail.com>
Date: Thu, 29 Mar 2018 03:55:50 +0100
Subject: [PATCH] Refactor removeProxyRules

---
 lib/compiler/passes/remove-proxy-rules.js | 39 +++++++----------------
 1 file changed, 12 insertions(+), 27 deletions(-)

diff --git a/lib/compiler/passes/remove-proxy-rules.js b/lib/compiler/passes/remove-proxy-rules.js
index 690dc08..d40b3b0 100644
--- a/lib/compiler/passes/remove-proxy-rules.js
+++ b/lib/compiler/passes/remove-proxy-rules.js
@@ -9,48 +9,33 @@ function removeProxyRules( ast, session, options ) {
 
     }
 
-    function replaceRuleRefs( ast, from, to ) {
+    const replaceRuleRefs = session.buildVisitor( {
 
-        const replace = session.buildVisitor( {
-            rule_ref( node ) {
+        rule_ref( node, proxy, real ) {
 
-                if ( node.name === from ) {
+            if ( node.name === proxy ) node.name = real;
 
-                    node.name = to;
-
-                }
-
-            }
-        } );
-
-        replace( ast );
+        }
 
-    }
+    } );
 
-    const indices = [];
+    const allowedStartRules = options.allowedStartRules;
+    const rules = [];
 
-    ast.rules.forEach( ( rule, i ) => {
+    for ( const rule of ast.rules ) {
 
         if ( isProxyRule( rule ) ) {
 
             replaceRuleRefs( ast, rule.name, rule.expression.name );
-            if ( options.allowedStartRules.indexOf( rule.name ) === -1 ) {
-
-                indices.push( i );
-
-            }
+            if ( allowedStartRules.indexOf( rule.name ) < 0 ) continue;
 
         }
 
-    } );
-
-    indices.reverse();
+        rules.push( rule );
 
-    indices.forEach( i => {
-
-        ast.rules.splice( i, 1 );
+    }
 
-    } );
+    ast.rules = rules;
 
 }