Add .NET Standard 2.0 Target (#35)

2.0 adds some things we were missing.
Primarily, we're interested in System.ICloneable.
Don't bother trying to bootstrap in 2.0, it won't work.

.travis.yml

@@ -1,13 +1,9 @@
 language: csharp
 sudo: required  
 dist: trusty  
-addons:  
-  apt:
-    packages:
-      - referenceassemblies-pcl
+dotnet: 2.0.0
 mono:  
   - latest
-solution: NetTopologySuite.sln
 install:  
   - nuget install NUnit.Runners -version 3.6.0 -OutputDirectory .testRunner
 script:

GeoAPI.nuspec

@@ -34,6 +34,7 @@
 				<dependency id="System.Runtime.Extensions" version="[4.3.0, )" />
 				<dependency id="System.Threading" version="[4.3.0, )" />
 			</group>
+			<group targetFramework=".NETStandard2.0" />
 		</dependencies>
 	</metadata>
 

src/GeoAPI/Consts.cs

@@ -35,6 +35,8 @@ internal static class Consts
     public const string Guid = FullFrameworkGuid;
 #elif NETSTANDARD1_0
     public const string Product = "GeoAPI.NetStandard10";
+#elif NETSTANDARD2_0
+    public const string Product = "GeoAPI.NetStandard20";
 #elif PCL
     public const string Product = "GeoAPI.PCL";
 #endif

src/GeoAPI/GeoAPI.csproj

@@ -2,7 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <SolutionDir Condition=" '$(SolutionDir)' == '' ">$(ProjectDir)..\..\</SolutionDir>
-    <TargetFrameworks>net20;net35-client;net35-cf;net40-client;net403-client;net45;netstandard1.0;portable40-net40+sl5+win8+wp8+wpa81;portable40-net403+sl5+win8+wp8+wpa81</TargetFrameworks>
+    <TargetFrameworks>net20;net35-client;net35-cf;net40-client;net403-client;net45;netstandard1.0;netstandard2.0;portable40-net40+sl5+win8+wp8+wpa81;portable40-net403+sl5+win8+wp8+wpa81</TargetFrameworks>
     <NoWarn>1591</NoWarn>
     <OutputPath>$(SolutionDir)$(Configuration)\$(Platform)</OutputPath>
     <DocumentationFile>$(OutputPath)\$(TargetFramework)\$(AssemblyName).xml</DocumentationFile>
@@ -89,8 +89,15 @@
     <RequiresFrameworkAssemblyReferences>true</RequiresFrameworkAssemblyReferences>
     <DebugType>full</DebugType>
 
+    <!-- NetFX targets set GeometryServiceProvider.Instance using reflection if it's not explicitly
+         set externally before the first access.  This is sketchy at best (it won't work if, e.g.,
+         someone tries this before the first thing loads NetTopologySuite into the AppDomain), so
+         other targets need to either explicitly bootstrap or just not use that global variable. -->
+    <DefineConstants>$(DefineConstants);COMPAT_BOOTSTRAP_USING_REFLECTION</DefineConstants>
+
     <DefineConstants>$(DefineConstants);FEATURE_DEFAULT_PARAMETERS</DefineConstants>
     <DefineConstants>$(DefineConstants);FEATURE_INTERFACE_VARIANCE</DefineConstants>
+
     <DefineConstants>$(DefineConstants);HAS_SYSTEM_APPDOMAIN_GETASSEMBLIES</DefineConstants>
     <DefineConstants>$(DefineConstants);HAS_SYSTEM_APPLICATIONEXCEPTION</DefineConstants>
     <DefineConstants>$(DefineConstants);HAS_SYSTEM_DOUBLE_TRYPARSE</DefineConstants>
@@ -105,13 +112,24 @@
 
   <PropertyGroup Condition=" '$(TargetFramework)' == 'netstandard1.0' ">
     <DisableImplicitFrameworkReferences>true</DisableImplicitFrameworkReferences>
+  </PropertyGroup>
 
+  <PropertyGroup Condition=" '$(TargetFramework)' == 'netstandard1.0' Or '$(TargetFramework)' == 'netstandard2.0' ">
     <DefineConstants>$(DefineConstants);FEATURE_DEFAULT_PARAMETERS</DefineConstants>
     <DefineConstants>$(DefineConstants);FEATURE_INTERFACE_VARIANCE</DefineConstants>
+
     <DefineConstants>$(DefineConstants);HAS_SYSTEM_DOUBLE_TRYPARSE</DefineConstants>
     <DefineConstants>$(DefineConstants);HAS_SYSTEM_STRING_TOUPPERINVARIANT</DefineConstants>
   </PropertyGroup>
 
+  <PropertyGroup Condition=" '$(TargetFramework)' == 'netstandard2.0' ">
+    <DefineConstants>$(DefineConstants);HAS_SYSTEM_APPDOMAIN_GETASSEMBLIES</DefineConstants>
+    <DefineConstants>$(DefineConstants);HAS_SYSTEM_APPLICATIONEXCEPTION</DefineConstants>
+    <DefineConstants>$(DefineConstants);HAS_SYSTEM_ICLONEABLE</DefineConstants>
+    <DefineConstants>$(DefineConstants);HAS_SYSTEM_SERIALIZABLEATTRIBUTE</DefineConstants>
+    <DefineConstants>$(DefineConstants);HAS_SYSTEM_STRING_TOUPPER_CULTUREINFO</DefineConstants>
+  </PropertyGroup>
+
   <ItemGroup Condition=" '$(RequiresFrameworkAssemblyReferences)' == 'true' ">
     <Reference Include="System" />
     <Reference Include="System.Core" Condition=" '$(TargetFramework)' != 'net20' " />

src/GeoAPI/GeometryServiceProvider.cs

@@ -72,7 +72,7 @@ private static IEnumerable<Type> GetLoadableTypes(Assembly assembly)
 
         private static IGeometryServices ReflectInstance()
         {
-#if HAS_SYSTEM_APPDOMAIN_GETASSEMBLIES
+#if COMPAT_BOOTSTRAP_USING_REFLECTION && HAS_SYSTEM_APPDOMAIN_GETASSEMBLIES
             var a = AppDomain.CurrentDomain.GetAssemblies();
             foreach (var assembly in a)
             {