Improved GraphQLClientException message when there is only one GraphQ…

…L error. (ChilliCream#4528)

src/StrawberryShake/Client/src/Core/GraphQLClientException.cs

@@ -59,15 +59,28 @@ public GraphQLClientException(params IClientError[] errors)
                 throw new ArgumentNullException(nameof(errors));
             }
 
-            var message = new StringBuilder("Multiple errors occured:");
-
-            foreach (var error in errors)
+            if (errors.Length == 0)
+            {
+                Message = "Unknown error occurred";
+            }
+            else if (errors.Length == 1)
             {
-                message.Append("- ");
-                message.AppendLine(error.Message);
+                Message = errors[0].Message;
+            }
+            else
+            {
+                var message = new StringBuilder("Multiple errors occurred:");
+
+                foreach (IClientError error in errors)
+                {
+                    message.AppendLine();
+                    message.Append("- ");
+                    message.Append(error.Message);
+                }
+
+                Message = message.ToString();
             }
 
-            Message = message.ToString();
             Errors = errors;
         }
 

src/StrawberryShake/Client/test/Core.Tests/GraphQLClientExceptionTests.cs

@@ -0,0 +1,55 @@
+using Xunit;
+
+namespace StrawberryShake
+{
+    public class GraphQLClientExceptionTests
+    {
+        [Fact]
+        public void Constructor_ZeroErrors()
+        {
+            //arrange
+            var errors = new IClientError[0];
+
+            //act
+            var exception = new GraphQLClientException(errors);
+
+            //assert
+            Assert.Equal("Unknown error occurred", exception.Message);
+        }
+
+        [Fact]
+        public void Constructor_OneError()
+        {
+            //arrange
+            var errors = new IClientError[]
+            {
+                new ClientError("some message"),
+            };
+
+            //act
+            var exception = new GraphQLClientException(errors);
+
+            //assert
+            Assert.Equal("some message", exception.Message);
+        }
+
+        [Fact]
+        public void Constructor_TwoErrors()
+        {
+            //arrange
+            var errors = new IClientError[]
+            {
+                new ClientError("first message"),
+                new ClientError("second message"),
+            };
+
+            //act
+            var exception = new GraphQLClientException(errors);
+
+            //assert
+            Assert.Equal(@"Multiple errors occurred:
+- first message
+- second message", exception.Message.Replace("\r", ""));
+        }
+    }
+}