[generator] Improve BI1014 - include name of unsupported field and update valid types on docs, fixes bug 57094. (#3001)

* [generator] Improve BI1014 - include name of unsupported field and update valid types on docs, fixes bug 57094.

https://bugzilla.xamarin.com/show_bug.cgi?id=57094

* Implement feedback

* fix error message

* More feedback

docs/website/binding_types_reference_guide.md

@@ -1380,7 +1380,19 @@ static library, use "__Internal" as the `libraryName` parameter.
 
 The generated properties are always static.
 
-Properties flagged with the Field attribute can be of type `NSString`, `NSArray`, `nint`, `double`, `nfloat` or `System.IntPtr`.
+Properties flagged with the Field attribute can be of the following types:
+
+* `NSString`
+* `NSArray`
+* `nint` / `int` / `long`
+* `nuint` / `uint` / `ulong`
+* `nfloat` / `float`
+* `double`
+* `CGSize`
+* `System.IntPtr`
+* Enums
+
+Setters are not supported for [enums backed by NSString constants](#enum-attributes), but they can be manually bound if needed.
 
 Example:
 

docs/website/generator-errors.md

@@ -70,7 +70,9 @@ This usually indicates a bug in Xamarin.iOS/Xamarin.Mac; please [file a bug repo
 
 ### <a name='BI1013'/>BI1013: Unsupported type for Fields (string), you probably meant NSString
 
-### <a name='BI1014'/>BI1014: Unsupported type for Fields: *
+### <a name='BI1014'/>BI1014: Unsupported type for Fields: * for '*'.
+
+Please go to [[FieldAttribute]](https://developer.xamarin.com/guides/cross-platform/macios/binding/binding-types-reference/#FieldAttribute) documentation to see supported types.
 
 ### <a name='BI1015'/>BI1015: In class * You specified the Events property, but did not bind those to names with Delegates
 

src/generator.cs

@@ -6223,7 +6223,7 @@ public partial class Generator : IMemberGatherer {
 							else if (btype == TypeManager.System_nuint || btype == TypeManager.System_UInt64)
 								print ($"return ({fieldTypeName}) (ulong) Dlfcn.GetNUInt (Libraries.{library_name}.Handle, \"{fieldAttr.SymbolName}\");");
 							else
-								throw new BindingException (1014, true, "Unsupported type for Fields: {0}", fieldTypeName);
+								throw new BindingException (1014, true, $"Unsupported type for Fields: {fieldTypeName} for '{field_pi}'.");
 						} else {
 							if (btype == TypeManager.System_Int32)
 								print ($"return ({fieldTypeName}) Dlfcn.GetInt32 (Libraries.{library_name}.Handle, \"{fieldAttr.SymbolName}\");");
@@ -6234,13 +6234,13 @@ public partial class Generator : IMemberGatherer {
 							else if (btype == TypeManager.System_UInt64)
 								print ($"return ({fieldTypeName}) Dlfcn.GetUInt64 (Libraries.{library_name}.Handle, \"{fieldAttr.SymbolName}\");");
 							else
-								throw new BindingException (1014, true, "Unsupported type for Fields: {0}", fieldTypeName);
+								throw new BindingException (1014, true, $"Unsupported type for Fields: {fieldTypeName} for '{field_pi}'.");
 						}
 					} else {
 						if (field_pi.PropertyType == TypeManager.System_String)
 							throw new BindingException (1013, true, "Unsupported type for Fields (string), you probably meant NSString");
 						else
-							throw new BindingException (1014, true, "Unsupported type for Fields: {0}", fieldTypeName);
+							throw new BindingException (1014, true, $"Unsupported type for Fields: {fieldTypeName} for '{field_pi}'.");
 					}
 					
 					indent--;

tests/generator/ErrorTests.cs

@@ -213,5 +213,29 @@ namespace Bug57804TestsRef {
 			bgen.AssertExecuteError ("build");
 			bgen.AssertError (1048, "Unsupported type 'ref/out NSValue' decorated with [BindAs]");
 		}
+
+		[Test]
+		public void Bug57094Test ()
+		{
+			// https://bugzilla.xamarin.com/show_bug.cgi?id=57094
+			var bgen = new BGenTool ();
+			bgen.Profile = Profile.iOS;
+			bgen.CreateTemporaryBinding (@"
+using System;
+using Foundation;
+using ObjCRuntime;
+
+namespace Bug57094 {
+
+	[BaseType (typeof (NSObject))]
+	interface FooObject {
+
+		[Field (""SomeField"", ""__Internal"")]
+		byte [] SomeField { get; }
+	}
+}");
+			bgen.AssertExecuteError ("build");
+			bgen.AssertError (1014, "Unsupported type for Fields: byte[] for 'Bug57094.FooObject SomeField'.");
+		}
 	}
 }