Merge pull request #1411 from SimonCropp/use-some-range-indexors

use some range indexors

Author: baywet

test/Microsoft.OpenApi.Readers.Tests/OpenApiReaderTests/OpenApiDiagnosticTests.cs

@@ -71,7 +71,7 @@ public Stream Load(Uri uri)
         public Task<Stream> LoadAsync(Uri uri)
         {
             var path = new Uri(new("http://example.org/OpenApiReaderTests/Samples/OpenApiDiagnosticReportMerged/"), uri).AbsolutePath;
-            path = path.Substring(1); // remove leading slash
+            path = path[1..]; // remove leading slash
             return Task.FromResult(Resources.GetStream(path));
         }
     }

test/Microsoft.OpenApi.Readers.Tests/OpenApiWorkspaceTests/OpenApiWorkspaceStreamTests.cs

@@ -108,7 +108,7 @@ public Stream Load(Uri uri)
         public Task<Stream> LoadAsync(Uri uri)
         {
             var path = new Uri(new("http://example.org/V3Tests/Samples/OpenApiWorkspace/"), uri).AbsolutePath;
-            path = path.Substring(1); // remove leading slash
+            path = path[1..]; // remove leading slash
             return Task.FromResult(Resources.GetStream(path));
         }
     }

test/Microsoft.OpenApi.Tests/Services/OpenApiUrlTreeNodeTests.cs

@@ -199,10 +199,10 @@ public void AttachPathWorks()
             rootNode.Attach(path2, pathItem2, label2);
 
             Assert.Equal(4, rootNode.Children.Count);
-            Assert.True(rootNode.Children.ContainsKey(path1.Substring(1)));
-            Assert.True(rootNode.Children.ContainsKey(path2.Substring(1)));
-            Assert.True(rootNode.Children[path1.Substring(1)].PathItems.ContainsKey(label1));
-            Assert.True(rootNode.Children[path2.Substring(1)].PathItems.ContainsKey(label2));
+            Assert.True(rootNode.Children.ContainsKey(path1[1..]));
+            Assert.True(rootNode.Children.ContainsKey(path2[1..]));
+            Assert.True(rootNode.Children[path1[1..]].PathItems.ContainsKey(label1));
+            Assert.True(rootNode.Children[path2[1..]].PathItems.ContainsKey(label2));
         }
 
         [Fact]