From da9091716f72e22e238f4ebb96eb1ae87b937f25 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=A9r=C3=B4me=20Piquot?= <jpiquot@fiveforty.fr>
Date: Sun, 16 Dec 2018 19:09:45 +0100
Subject: [PATCH] Settings[nameof(ContentTypeSettings.Stereotype)] can return a
 null value. So calling
 Settings[nameof(ContentTypeSettings.Stereotype)].ToString() can throw a null
 reference exception.

---
 .../ContentPartDisplayDriverTPart.cs          | 102 +++++++-----------
 1 file changed, 37 insertions(+), 65 deletions(-)

diff --git a/src/OrchardCore/OrchardCore.ContentManagement.Display/ContentDisplay/ContentPartDisplayDriverTPart.cs b/src/OrchardCore/OrchardCore.ContentManagement.Display/ContentDisplay/ContentPartDisplayDriverTPart.cs
index 4a1816d9ba8..6c4469d6528 100644
--- a/src/OrchardCore/OrchardCore.ContentManagement.Display/ContentDisplay/ContentPartDisplayDriverTPart.cs
+++ b/src/OrchardCore/OrchardCore.ContentManagement.Display/ContentDisplay/ContentPartDisplayDriverTPart.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Threading.Tasks;
+
 using OrchardCore.ContentManagement.Display.Models;
 using OrchardCore.ContentManagement.Metadata.Models;
 using OrchardCore.ContentManagement.Metadata.Settings;
@@ -18,6 +19,18 @@ namespace OrchardCore.ContentManagement.Display.ContentDisplay
     {
         private ContentTypePartDefinition _typePartDefinition;
 
+        public virtual IDisplayResult Display(TPart part, BuildPartDisplayContext context) => Display(part);
+
+        public virtual IDisplayResult Display(TPart part) => null;
+
+        public virtual Task<IDisplayResult> DisplayAsync(TPart part, BuildPartDisplayContext context) => Task.FromResult(Display(part, context));
+
+        public virtual IDisplayResult Edit(TPart part, BuildPartEditorContext context) => Edit(part);
+
+        public virtual IDisplayResult Edit(TPart part) => null;
+
+        public virtual Task<IDisplayResult> EditAsync(TPart part, BuildPartEditorContext context) => Task.FromResult(Edit(part, context));
+
         public override ShapeResult Factory(string shapeType, Func<IBuildShapeContext, Task<IShape>> shapeBuilder, Func<IShape, Task> initializeAsync)
         {
             // e.g., HtmlBodyPart.Summary, HtmlBodyPart-BlogPost, BagPart-LandingPage-Services
@@ -29,18 +42,25 @@ public override ShapeResult Factory(string shapeType, Func<IBuildShapeContext, T
             {
                 // The stereotype is used when not displaying for a specific content type. We don't use [Stereotype] and [ContentType] at
                 // the same time in an alternate because a content type is always of one stereotype.
-
-                var stereotype = _typePartDefinition.ContentTypeDefinition.Settings[nameof(ContentTypeSettings.Stereotype)].ToString();
-
-                if (String.IsNullOrEmpty(stereotype) || String.Equals("Content", stereotype, StringComparison.OrdinalIgnoreCase))
+                string stereotype;
+                var stereotypeSetting = _typePartDefinition.ContentTypeDefinition?.Settings[nameof(ContentTypeSettings.Stereotype)];
+                if (stereotypeSetting != null)
                 {
-                    stereotype = "";
+                    stereotype = stereotypeSetting.ToString();
+                    if (String.IsNullOrEmpty(stereotype) || String.Equals("Content", stereotype, StringComparison.OrdinalIgnoreCase))
+                    {
+                        stereotype = "";
+                    }
+                    else
+                    {
+                        stereotype = stereotype + "__";
+                    }
                 }
                 else
                 {
-                    stereotype = stereotype + "__";
+                    stereotype = "";
                 }
-                
+
                 var partName = _typePartDefinition.Name;
                 var partType = _typePartDefinition.PartDefinition.Name;
                 var contentType = _typePartDefinition.ContentTypeDefinition.Name;
@@ -134,6 +154,12 @@ public override ShapeResult Factory(string shapeType, Func<IBuildShapeContext, T
             return result;
         }
 
+        public virtual Task<IDisplayResult> UpdateAsync(TPart part, IUpdateModel updater, UpdatePartEditorContext context) => UpdateAsync(part, context);
+
+        public virtual Task<IDisplayResult> UpdateAsync(TPart part, BuildPartEditorContext context) => UpdateAsync(part, context.Updater);
+
+        public virtual Task<IDisplayResult> UpdateAsync(TPart part, IUpdateModel updater) => Task.FromResult<IDisplayResult>(null);
+
         async Task<IDisplayResult> IContentPartDisplayDriver.BuildDisplayAsync(ContentPart contentPart, ContentTypePartDefinition typePartDefinition, BuildDisplayContext context)
         {
             var part = contentPart as TPart;
@@ -198,51 +224,6 @@ async Task<IDisplayResult> IContentPartDisplayDriver.UpdateEditorAsync(ContentPa
             return result;
         }
 
-        public virtual Task<IDisplayResult> DisplayAsync(TPart part, BuildPartDisplayContext context)
-        {
-            return Task.FromResult(Display(part, context));
-        }
-
-        public virtual IDisplayResult Display(TPart part, BuildPartDisplayContext context)
-        {
-            return Display(part);
-        }
-
-        public virtual IDisplayResult Display(TPart part)
-        {
-            return null;
-        }
-
-        public virtual Task<IDisplayResult> EditAsync(TPart part, BuildPartEditorContext context)
-        {
-            return Task.FromResult(Edit(part, context));
-        }
-
-        public virtual IDisplayResult Edit(TPart part, BuildPartEditorContext context)
-        {
-            return Edit(part);
-        }
-
-        public virtual IDisplayResult Edit(TPart part)
-        {
-            return null;
-        }
-
-        public virtual Task<IDisplayResult> UpdateAsync(TPart part, IUpdateModel updater, UpdatePartEditorContext context)
-        {
-            return UpdateAsync(part, context);
-        }
-
-        public virtual Task<IDisplayResult> UpdateAsync(TPart part, BuildPartEditorContext context)
-        {
-            return UpdateAsync(part, context.Updater);
-        }
-
-        public virtual Task<IDisplayResult> UpdateAsync(TPart part, IUpdateModel updater)
-        {
-            return Task.FromResult<IDisplayResult>(null);
-        }
-
         protected string GetEditorShapeType(string shapeType, ContentTypePartDefinition typePartDefinition)
         {
             var editor = typePartDefinition.Editor();
@@ -251,20 +232,11 @@ protected string GetEditorShapeType(string shapeType, ContentTypePartDefinition
                 : shapeType;
         }
 
-        protected string GetEditorShapeType(string shapeType, BuildPartEditorContext context)
-        {
-            return GetEditorShapeType(shapeType, context.TypePartDefinition);
-        }
+        protected string GetEditorShapeType(string shapeType, BuildPartEditorContext context) => GetEditorShapeType(shapeType, context.TypePartDefinition);
 
-        protected string GetEditorShapeType(ContentTypePartDefinition typePartDefinition)
-        {
-            return GetEditorShapeType(typeof(TPart).Name + "_Edit", typePartDefinition);
-        }
+        protected string GetEditorShapeType(ContentTypePartDefinition typePartDefinition) => GetEditorShapeType(typeof(TPart).Name + "_Edit", typePartDefinition);
 
-        protected string GetEditorShapeType(BuildPartEditorContext context)
-        {
-            return GetEditorShapeType(context.TypePartDefinition);
-        }
+        protected string GetEditorShapeType(BuildPartEditorContext context) => GetEditorShapeType(context.TypePartDefinition);
 
         private void BuildPrefix(ContentTypePartDefinition typePartDefinition, string htmlFieldPrefix)
         {
@@ -276,4 +248,4 @@ private void BuildPrefix(ContentTypePartDefinition typePartDefinition, string ht
             }
         }
     }
-}
+}
\ No newline at end of file