NLogConfigurationException - Improve styling of error-message when fa…

…iling to assign config-property (NLog#4809)

src/NLog/Config/LoggingConfigurationParser.cs

@@ -1069,7 +1069,7 @@ private void SetPropertyValueFromString(object targetObject, string propertyName
  if (ex.MustBeRethrownImmediately())
  throw;
 
- var configException = new NLogConfigurationException($"Error when setting value '{propertyValue}' for property '{propertyName}' on {targetObject?.GetType()} in section '{element.Name}'", ex);
+ var configException = new NLogConfigurationException($"'{targetObject?.GetType()?.Name}' cannot assign property '{propertyName}'='{propertyValue}' in section '{element.Name}'. Error: {ex.Message}", ex);
  if (MustThrowConfigException(configException))
  throw;
  }
@@ -1090,7 +1090,7 @@ private void SetPropertyValuesFromElement(object o, ValidatedConfigurationElemen
  {
  if (!PropertyHelper.TryGetPropertyInfo(o, childElement.Name, out var propInfo))
  {
- var configException = new NLogConfigurationException($"Unknown property '{childElement.Name}' for '{o?.GetType()}' in section '{parentElement.Name}'");
+ var configException = new NLogConfigurationException($"'{o?.GetType()?.Name}' cannot assign unknown property '{childElement.Name}' in section '{parentElement.Name}'");
  if (MustThrowConfigException(configException))
  throw configException;
 

src/NLog/Internal/Reflection/PropertyHelper.cs

@@ -96,7 +96,7 @@ internal static void SetPropertyFromString(object obj, string propertyName, stri
 
  if (!TryGetPropertyInfo(objType, propertyName, out var propInfo))
  {
- throw new NLogConfigurationException($"Unknown property '{propertyName}'='{value}' for '{objType.Name}'");
+ throw new NLogConfigurationException($"'{objType?.Name}' cannot assign unknown property '{propertyName}'='{value}'");
  }
 
  SetPropertyFromString(obj, propertyName, value, propInfo, configurationItemFactory);
@@ -112,7 +112,7 @@ internal static void SetPropertyFromString(object obj, string propertyName, stri
  {
  if (propInfo.IsDefined(_arrayParameterAttribute.GetType(), false))
  {
- throw new NotSupportedException($"Property {propertyName} on {obj.GetType().Name} is an array, and cannot be assigned a scalar value: '{value}'.");
+ throw new NotSupportedException($"'{obj?.GetType()?.Name}' cannot assign property '{propertyName}', because property of type array and not scalar value: '{value}'.");
  }
 
  propertyType = Nullable.GetUnderlyingType(propertyType) ?? propertyType;
@@ -128,7 +128,7 @@ internal static void SetPropertyFromString(object obj, string propertyName, stri
  }
  catch (TargetInvocationException ex)
  {
- throw new NLogConfigurationException($"Error when setting property '{propInfo.Name}'='{value}' on {obj.GetType().Name}", ex.InnerException);
+ throw new NLogConfigurationException($"'{obj?.GetType()?.Name}' cannot assign property '{propInfo.Name}'='{value}'", ex.InnerException ?? ex);
  }
  catch (Exception exception)
  {
@@ -137,7 +137,7 @@ internal static void SetPropertyFromString(object obj, string propertyName, stri
  throw;
  }
 
- throw new NLogConfigurationException($"Error when setting property '{propInfo.Name}'='{value}' on {obj.GetType().Name}", exception);
+ throw new NLogConfigurationException($"'{obj?.GetType()?.Name}' cannot assign property '{propInfo.Name}'='{value}'. Error={exception.Message}", exception);
  }
  }
 

src/NLog/Layouts/LayoutParser.cs

@@ -461,7 +461,7 @@ private static LayoutRenderer ParseLayoutRenderer(ConfigurationItemFactory confi
  var value = ParseParameterValue(stringReader);
  if (!string.IsNullOrEmpty(parameterName) || !StringHelpers.IsNullOrWhiteSpace(value))
  {
- var configException = new NLogConfigurationException($"Unknown property '{parameterName}=' for ${{{typeName}}} ({layoutRenderer?.GetType()})");
+ var configException = new NLogConfigurationException($"${{{typeName}}} cannot assign unknown property '{parameterName}='");
  if (throwConfigExceptions ?? configException.MustBeRethrown())
  {
  throw configException;
@@ -522,7 +522,7 @@ private static string ValidatePreviousParameterName(string previousParameterName
  {
  if (parameterName?.Equals(previousParameterName, StringComparison.OrdinalIgnoreCase) == true)
  {
- var configException = new NLogConfigurationException($"Same property '{parameterName}' assigned twice for {layoutRenderer?.GetType()} ");
+ var configException = new NLogConfigurationException($"'{layoutRenderer?.GetType()?.Name}' has same property '{parameterName}=' assigned twice");
  if (throwConfigExceptions ?? configException.MustBeRethrown())
  {
  throw configException;
@@ -590,7 +590,7 @@ private static string SetDefaultPropertyValue(string value, LayoutRenderer layou
  }
  else
  {
- var configException = new NLogConfigurationException($"{layoutRenderer.GetType()} has no default property to assign value {value}");
+ var configException = new NLogConfigurationException($"'{layoutRenderer?.GetType()?.Name}' has no default property to assign value {value}");
  if (throwConfigExceptions ?? configException.MustBeRethrown())
  {
  throw configException;

tests/NLog.UnitTests/Internal/Reflection/PropertyHelperTests.cs

@@ -62,7 +62,7 @@ public void AssignArrayPropertyFromStringWillResultInNotSupportedExceptionSomeWh
  // Assert
  Assert.IsType<NLogConfigurationException>(ex.InnerException);
  Assert.IsType<NotSupportedException>(ex.InnerException.InnerException);
- Assert.Contains("is an array, and cannot be assigned a scalar value", ex.InnerException.InnerException.Message);
+ Assert.Contains("because property of type array and not scalar value", ex.InnerException.InnerException.Message);
  }
  }
 }

tests/NLog.UnitTests/Layouts/SimpleLayoutParserTests.cs

@@ -71,6 +71,18 @@ public void UnknownLayoutRenderer()
  Assert.Throws<NLogConfigurationException>(() => new SimpleLayout("'${{unknown-type}}'"));
  }
 
+ [Fact]
+ public void UnknownLayoutRendererProperty()
+ {
+ Assert.Throws<NLogConfigurationException>(() => new SimpleLayout("'${message:unknown_item=${unknown-value}}'"));
+ }
+
+ [Fact]
+ public void UnknownLayoutRendererPropertyValue()
+ {
+ Assert.Throws<NLogConfigurationException>(() => new SimpleLayout("'${message:withexception=${unknown-value}}'"));
+ }
+
  [Fact]
  public void SingleParamTest()
  {