From 9f1e389441bb5ec92338c216df45efbcd0a008de Mon Sep 17 00:00:00 2001
From: Ben Lichtman <belichtm@microsoft.com>
Date: Wed, 18 Dec 2019 10:44:40 -0800
Subject: [PATCH] Remove unnecessary internal tags, handle bad input

---
 src/server/scriptInfo.ts | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/server/scriptInfo.ts b/src/server/scriptInfo.ts
index e3f4bd2d195..53bbc6cba75 100644
--- a/src/server/scriptInfo.ts
+++ b/src/server/scriptInfo.ts
@@ -622,6 +622,7 @@ namespace ts.server {
         }
 
         positionToLineOffset(position: number): protocol.Location {
+            failIfInvalidPosition(position);
             const location = this.textStorage.positionToLineOffset(position);
             failIfInvalidLocation(location);
             return location;
@@ -645,7 +646,11 @@ namespace ts.server {
         }
     }
 
-    /*@internal*/
+    function failIfInvalidPosition(position: number) {
+        Debug.assert(typeof position === "number", `Expected position ${position} to be a number.`);
+        Debug.assert(position >= 0, `Expected position to be non-negative.`);
+    }
+
     function failIfInvalidLocation(location: protocol.Location) {
         Debug.assert(typeof location.line === "number", `Expected line ${location.line} to be a number.`);
         Debug.assert(typeof location.offset === "number", `Expected offset ${location.offset} to be a number.`);