Use Moq for mocking objects, write more tests

test/Discord.Net.Commands.Tests/CommandServiceConfigTests.Data.cs

@@ -16,11 +16,13 @@ namespace Discord.Net.Commands.Tests
             new CommandServiceConfig{ SeparatorChar = '"'}
         }.Select(x => new object[] { x, x.SeparatorChar });
 
-        public static IEnumerable<string> DefaultAliases => _defaultAliases;
-        private static readonly IEnumerable<string> _defaultAliases = new List<string>
+        public static IEnumerable<object[]> CaseSensitivityTestData => _caseSensitivityTestData;
+        private static readonly IEnumerable<object[]> _caseSensitivityTestData = new object[][]
         {
-            "debug ping",
-            "debug pong"
+            new object[]{  true, false },
+            new object[]{  true,  true },
+            new object[]{ false,  true },
+            new object[]{ false, false }
         };
     }
 }

test/Discord.Net.Commands.Tests/CommandServiceConfigTests.cs

@@ -1,4 +1,5 @@
 using Discord.Commands;
+using Moq;
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -14,37 +15,40 @@ namespace Discord.Net.Commands.Tests
         public async Task CommandSeparators(CommandServiceConfig config, char separatorChar)
         {
             var service = new CommandService(config);
-            var module = await service.AddModuleAsync(typeof(DummyModule)).ConfigureAwait(false);
+            await service.AddModuleAsync(typeof(DummyModule)).ConfigureAwait(false);
 
-            Assert.True(CommandsLoaded(service, separatorChar));
+            var contextMock = new Mock<ICommandContext>();
+            var context = contextMock.Object;
 
-            var dummyContext = new DummyCommandContext();
-
-            foreach (var _alias in DefaultAliases)
+            foreach (var _name in DummyModule.CommandNames)
             {
-                var alias = _alias.Replace(' ', separatorChar);
+                var name = _name.Replace(' ', separatorChar);
 
-                var result = service.Search(dummyContext, alias);
+                var result = service.Search(context, name);
                 Assert.True(result.IsSuccess, result.ErrorReason);
             }
         }
 
-        public bool CommandsLoaded(CommandService service, char separatorChar)
+        [Theory]
+        [MemberData(nameof(CaseSensitivityTestData), MemberType = typeof(CommandServiceConfigTests))]
+        public async Task CaseSensitivity(bool caseSensitive, bool upperCase)
         {
-            if (!service.Commands.Any())
-                return false;
+            var service = new CommandService(new CommandServiceConfig { CaseSensitiveCommands = caseSensitive });
+            await service.AddModuleAsync(typeof(DummyModule)).ConfigureAwait(false);
 
-            var loadedAliases = service.Commands.SelectMany(x => x.Aliases);
+            var contextMock = new Mock<ICommandContext>();
+            var context = contextMock.Object;
 
-            foreach (var alias in DefaultAliases)
+            foreach (var _name in DummyModule.CommandNames)
             {
-                if (!loadedAliases.Contains(alias.Replace(' ', separatorChar)))
-                {
-                    return false;
-                }
-            }
+                var name = upperCase ? _name.ToUpper() : _name;
 
-            return true;
+                var result = service.Search(context, name);
+                if (caseSensitive && upperCase)
+                    Assert.False(result.IsSuccess, $"Searching for `{name}` returned successfully");
+                else
+                    Assert.True(result.IsSuccess, result.ErrorReason);
+            }
         }
     }
 }

test/Discord.Net.Commands.Tests/CommandServiceTests.cs

@@ -0,0 +1,45 @@
+using Discord.Commands;
+using System;
+using System.Linq;
+using System.Threading.Tasks;
+using Xunit;
+
+namespace Discord.Net.Commands.Tests
+{
+    class CommandServiceTests
+    {
+        [Fact]
+        public async Task CommandsLoad()
+        {
+            var service = new CommandService();
+
+            var module = await service.AddModuleAsync(typeof(DummyModule)).ConfigureAwait(false);
+            Assert.NotNull(module);
+
+            var commandAliases = module.Commands.SelectMany(x => x.Aliases);
+
+            foreach (var name in DummyModule.CommandNames)
+            {
+                Assert.True(commandAliases.Contains(name), $"The loaded module did not contain the command {name}");
+            }
+        }
+
+        [Fact]
+        public async Task MultipleLoadsThrows()
+        {
+            var service = new CommandService();
+
+            var module = await service.AddModuleAsync(typeof(DummyModule)).ConfigureAwait(false);
+            await Assert.ThrowsAsync<ArgumentException>(() => service.AddModuleAsync(typeof(DummyModule)))
+                .ConfigureAwait(false);
+        }
+
+        [Fact]
+        public async Task InvalidTypeThrows()
+        {
+            var service = new CommandService();
+            await Assert.ThrowsAsync<InvalidOperationException>(() => service.AddModuleAsync(typeof(CommandServiceTests)))
+                .ConfigureAwait(false);
+        }
+    }
+}

test/Discord.Net.Commands.Tests/Discord.Net.Commands.Tests.csproj

@@ -12,6 +12,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.0.0" />
+    <PackageReference Include="Moq" Version="4.7.25" />
     <PackageReference Include="xunit" Version="2.2.0" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.2.0" />
   </ItemGroup>

test/Discord.Net.Commands.Tests/DummyCommandContext.cs

@@ -1,20 +0,0 @@
-using Discord.Commands;
-using System;
-using System.Collections.Generic;
-using System.Text;
-
-namespace Discord.Net.Commands.Tests
-{
-    class DummyCommandContext : ICommandContext
-    {
-        public IDiscordClient Client { get; set; }
-
-        public IGuild Guild { get; set; }
-
-        public IMessageChannel Channel { get; set; }
-
-        public IUser User { get; set; }
-
-        public IUserMessage Message { get; set; }
-    }
-}

test/Discord.Net.Commands.Tests/DummyModule.cs

@@ -20,5 +20,19 @@ namespace Discord.Net.Commands.Tests
         {
             return Task.Delay(0);
         }
+
+        //NOTE: do not add this to CommandNames: it is intentional for this command to not be loaded!
+        [Command("doesNotLoad")]
+        private Task DoesNotLoadAsync()
+        {
+            return Task.Delay(0);
+        }
+
+        public static IEnumerable<string> CommandNames => _commandNames;
+        private static readonly IEnumerable<string> _commandNames = new List<string>
+        {
+            "debug ping",
+            "debug pong"
+        };
     }
 }