From 0c1d459bc94767797dda4c56ac82c2fb8449be13 Mon Sep 17 00:00:00 2001
From: David Wilson <daviwil@microsoft.com>
Date: Mon, 12 Jun 2017 11:52:24 -0700
Subject: [PATCH] Handle null case in ReferencesCodeLensProvider's CodeLens
 resolver

This change fixes an issue where a null case isn't being handled
gracefully in the ReferencesCodeLensProvider when resolving a CodeLens
while the user is typing out a new function defintion or doing anything
else that causes the code to change like formatting the script.

Resolves PowerShell/vscode-powershell#857
Resolves PowerShell/vscode-powershell#855
---
 .../CodeLens/CodeLensFeature.cs               |  3 ++-
 .../CodeLens/ReferencesCodeLensProvider.cs    | 22 ++++++++++---------
 2 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/src/PowerShellEditorServices.Host/CodeLens/CodeLensFeature.cs b/src/PowerShellEditorServices.Host/CodeLens/CodeLensFeature.cs
index 17bcc65b21..6907f4a170 100644
--- a/src/PowerShellEditorServices.Host/CodeLens/CodeLensFeature.cs
+++ b/src/PowerShellEditorServices.Host/CodeLens/CodeLensFeature.cs
@@ -147,7 +147,8 @@ await requestContext.SendResult(
                 }
                 else
                 {
-                    // TODO: Write error!
+                    await requestContext.SendError(
+                        $"Could not find provider for the original CodeLens: {codeLensData.ProviderId}");
                 }
             }
         }
diff --git a/src/PowerShellEditorServices.Host/CodeLens/ReferencesCodeLensProvider.cs b/src/PowerShellEditorServices.Host/CodeLens/ReferencesCodeLensProvider.cs
index 3d1efc79d5..1fedc6cc5b 100644
--- a/src/PowerShellEditorServices.Host/CodeLens/ReferencesCodeLensProvider.cs
+++ b/src/PowerShellEditorServices.Host/CodeLens/ReferencesCodeLensProvider.cs
@@ -64,16 +64,18 @@ await editorSession.LanguageService.FindReferencesOfSymbol(
                     references,
                     editorSession.Workspace);
 
-            var referenceLocations =
-                referencesResult
-                    .FoundReferences
-                    .Select(
-                        r => new Location
-                        {
-                            Uri = GetFileUri(r.FilePath),
-                            Range = r.ScriptRegion.ToRange()
-                        })
-                    .ToArray();
+            Location[] referenceLocations =
+                referencesResult == null
+                    ? new Location[0]
+                    : referencesResult
+                        .FoundReferences
+                        .Select(
+                            r => new Location
+                            {
+                                Uri = GetFileUri(r.FilePath),
+                                Range = r.ScriptRegion.ToRange()
+                            })
+                        .ToArray();
 
             return
                 new CodeLens(