Add a catch to wrap parsing/input errors

src/Discord.Net.Commands/Readers/NamedArgumentTypeReader.cs

@@ -10,8 +10,7 @@ namespace Discord.Commands
     internal sealed class NamedArgumentTypeReader<T> : TypeReader
         where T : class, new()
     {
-        private static readonly TypeInfo _tInfo = typeof(T).GetTypeInfo();
-        private static readonly IReadOnlyDictionary<string, PropertyInfo> _tProps = _tInfo.DeclaredProperties
+        private static readonly IReadOnlyDictionary<string, PropertyInfo> _tProps = typeof(T).GetTypeInfo().DeclaredProperties
             .Where(p => p.SetMethod != null && p.SetMethod.IsPublic && !p.SetMethod.IsStatic)
             .ToImmutableDictionary(p => p.Name, StringComparer.OrdinalIgnoreCase);
 
@@ -30,12 +29,20 @@ namespace Discord.Commands
 
             while (state != ReadState.End)
             {
-                var prop = Read(out var arg);
-                var propVal = await ReadArgumentAsync(prop, arg).ConfigureAwait(false);
-                if (propVal != null)
-                    prop.SetMethod.Invoke(result, new[] { propVal });
-                else
-                    return TypeReaderResult.FromError(CommandError.ParseFailed, $"Could not parse the argument for the parameter '{prop.Name}' as type '{prop.PropertyType}'.");
+                try
+                {
+                    var prop = Read(out var arg);
+                    var propVal = await ReadArgumentAsync(prop, arg).ConfigureAwait(false);
+                    if (propVal != null)
+                        prop.SetMethod.Invoke(result, new[] { propVal });
+                    else
+                        return TypeReaderResult.FromError(CommandError.ParseFailed, $"Could not parse the argument for the parameter '{prop.Name}' as type '{prop.PropertyType}'.");
+                }
+                catch (Exception ex)
+                {
+                    //TODO: use the Exception overload after a rebase on latest
+                    return TypeReaderResult.FromError(CommandError.Exception, ex.Message);
+                }
             }
 
             return TypeReaderResult.FromSuccess(result);
@@ -92,6 +99,9 @@ namespace Discord.Commands
                     }
                 }
 
+                if (currentParam == null)
+                    throw new InvalidOperationException("No parameter name was read.");
+
                 return GetPropAndValue(out arg);
 
                 PropertyInfo GetPropAndValue(out string argv)

test/Discord.Net.Tests/Tests.TypeReaders.cs

@@ -58,6 +58,28 @@ namespace Discord
             Assert.Equal(expected: 42, actual: m.Foo);
             Assert.Equal(expected: "hello", actual: m.Bar);
         }
+
+        [Fact]
+        public async Task TestNonPatternInput()
+        {
+            var commands = new CommandService();
+            var module = await commands.AddModuleAsync<TestModule>(null);
+
+            Assert.NotNull(module);
+            Assert.NotEmpty(module.Commands);
+
+            var cmd = module.Commands[0];
+            Assert.NotNull(cmd);
+            Assert.NotEmpty(cmd.Parameters);
+
+            var param = cmd.Parameters[0];
+            Assert.NotNull(param);
+            Assert.True(param.IsRemainder);
+
+            var result = await param.ParseAsync(null, "foobar");
+            Assert.False(result.IsSuccess);
+            Assert.Equal(expected: CommandError.Exception, actual: result.Error);
+        }
     }
 
     [NamedArgumentType]