From 940175e23f3dbfeecb5fc26a318c76e89f7844b1 Mon Sep 17 00:00:00 2001
From: Wesley Wigham <wwigham@gmail.com>
Date: Thu, 26 Oct 2017 13:01:48 -0700
Subject: [PATCH] Memoize rule provider (#19501)

---
 src/harness/unittests/extractTestHelpers.ts | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/src/harness/unittests/extractTestHelpers.ts b/src/harness/unittests/extractTestHelpers.ts
index ac4d1494811..b8974694cfe 100644
--- a/src/harness/unittests/extractTestHelpers.ts
+++ b/src/harness/unittests/extractTestHelpers.ts
@@ -67,7 +67,8 @@ namespace ts {
     }
 
     export const newLineCharacter = "\n";
-    export function getRuleProvider(action?: (opts: FormatCodeSettings) => void) {
+    export const getRuleProvider = memoize(getRuleProviderInternal);
+    function getRuleProviderInternal() {
         const options = {
             indentSize: 4,
             tabSize: 4,
@@ -89,9 +90,6 @@ namespace ts {
             placeOpenBraceOnNewLineForFunctions: false,
             placeOpenBraceOnNewLineForControlBlocks: false,
         };
-        if (action) {
-            action(options);
-        }
         const rulesProvider = new formatting.RulesProvider();
         rulesProvider.ensureUpToDate(options);
         return rulesProvider;