c#: Checking null for parameters generated code.

Checking null for generated code
ref T8399

Reviewed-by: Felipe Magno de Almeida <felipe@expertisesolutions.com.br>
Differential Revision: https://phab.enlightenment.org/D10970

src/bin/eolian_mono/eolian/mono/events.hh

@@ -165,7 +165,8 @@ struct pack_event_info_and_call_visitor
       if (regular.is_struct())
         {
            return as_generator(
-                indent << "IntPtr info = Marshal.AllocHGlobal(Marshal.SizeOf(e.arg));\n"
+                indent << "Contract.Requires(e != null, nameof(e));\n"
+                << indent << "IntPtr info = Marshal.AllocHGlobal(Marshal.SizeOf(e.arg));\n"
                 << indent << "CallNativeEventCallback(" + library_name + ", \"_" + evt_c_name + "\", info, " << "(p) => Marshal.FreeHGlobal(p));\n"
               ).generate(sink, attributes::unused, *context);
         }
@@ -192,7 +193,8 @@ struct pack_event_info_and_call_visitor
       auto str_accept_func = [&](std::string const& conversion)
         {
            return as_generator(
-             indent << "IntPtr info = Eina.StringConversion.ManagedStringToNativeUtf8Alloc(" << conversion << ");\n"
+             indent << "Contract.Requires(e != null, nameof(e));\n"
+             << indent << "IntPtr info = Eina.StringConversion.ManagedStringToNativeUtf8Alloc(" << conversion << ");\n"
              << indent << "CallNativeEventCallback(" + library_name + ", \"_" + evt_c_name + "\", info, " << "(p) => Eina.MemoryNative.Free(p));\n"
              ).generate(sink, attributes::unused, *context);
         };
@@ -210,7 +212,8 @@ struct pack_event_info_and_call_visitor
       auto value_accept_func = [&](std::string const& conversion)
         {
            return as_generator(
-             indent << "IntPtr info = Eina.PrimitiveConversion.ManagedToPointerAlloc(" << conversion << ");\n"
+             indent << "Contract.Requires(e != null, nameof(e));\n"
+             << indent << "IntPtr info = Eina.PrimitiveConversion.ManagedToPointerAlloc(" << conversion << ");\n"
              << indent << "CallNativeEventCallback(" + library_name + ", \"_" + evt_c_name + "\", info, " << "(p) => Marshal.FreeHGlobal(p));\n"
              ).generate(sink, attributes::unused, *context);
         };
@@ -223,7 +226,9 @@ struct pack_event_info_and_call_visitor
    bool operator()(grammar::attributes::klass_name const&) const
    {
       auto const& indent = current_indentation(*context);
-      return as_generator(indent << "IntPtr info = e.arg.NativeHandle;\n"
+      return as_generator(
+                          indent << "Contract.Requires(e != null, nameof(e));\n"
+                          << indent << "IntPtr info = e.arg.NativeHandle;\n"
                           << "CallNativeEventCallback(" << library_name << ", \"_" << evt_c_name << "\", IntPtr.Zero, null);\n"
                           ).generate(sink, attributes::unused, *context);
    }
@@ -233,7 +238,9 @@ struct pack_event_info_and_call_visitor
       if ((type.outer.base_type == "iterator") || (type.outer.base_type == "accessor"))
         return true;
 
-      return as_generator(indent << "IntPtr info = e.arg.Handle;\n"
+      return as_generator(
+                          indent << "Contract.Requires(e != null, nameof(e));\n"
+                          << indent << "IntPtr info = e.arg.Handle;\n"
                           << "CallNativeEventCallback(" << library_name << ", \"_" << evt_c_name << "\", IntPtr.Zero, null);\n"
                           ).generate(sink, attributes::unused, *context);
    }

src/bin/eolian_mono/eolian/mono/function_definition.hh

@@ -305,6 +305,7 @@ struct property_extension_method_definition_generator
           if (!as_generator(scope_tab << "public static Efl.BindableProperty<" << type(true) << "> " << managed_name << "<T>(this Efl.BindablePart<T> part, Efl.Csharp.ExtensionTag<"
                             << name_helpers::klass_full_concrete_or_interface_name(cls)
                             << ", T>magic = null) where T : " << name_helpers::klass_full_concrete_or_interface_name(cls) <<  " {\n"
+                            << scope_tab << scope_tab << "Contract.Requires(part != null, nameof(part));\n"
                             << scope_tab << scope_tab << "return new Efl.BindableProperty<" << type(true) << ">(part.PartName, \"" << property.name << "\", part.Binder);\n"
                             << scope_tab << "}\n\n"
                             ).generate(sink, std::make_tuple(prop_type, prop_type), context))

src/bin/eolian_mono/eolian/mono/parameter.hh

@@ -693,10 +693,10 @@ struct convert_in_variable_generator
         }
       else if (param.type.c_type == "Eina_Binbuf *" || param.type.c_type == "const Eina_Binbuf *")
         {
-           auto var_name = in_variable_name(param.param_name);
            if (!as_generator(
-                 "var " << string << " = " << escape_keyword(param.param_name) << ".Handle;\n"
-              ).generate(sink, var_name, context))
+                             "Contract.Requires(" << string << " != null, nameof(" << string << "));\n"
+                             << scope_tab(2) << "var " << string << " = " << string << ".Handle;\n"
+                             ).generate(sink, std::make_tuple(escape_keyword(param.param_name), escape_keyword(param.param_name), in_variable_name(param.param_name), escape_keyword(param.param_name)), context))
              return false;
            if (param.type.has_own)
              {
@@ -710,10 +710,10 @@ struct convert_in_variable_generator
            attributes::complex_type_def const* complex = efl::eina::get<attributes::complex_type_def>(&param.type.original_type);
            if (!complex || complex->subtypes.size() != 2)
              return false;
-           auto var_name = in_variable_name(param.param_name);
            if (!as_generator(
-                 "var " << string << " = " << escape_keyword(param.param_name) << ".Handle;\n"
-              ).generate(sink, var_name, context))
+                             "Contract.Requires(" << string << " != null, nameof(" << string << "));\n"
+                             << scope_tab(2) << "var " << string << " = " << string << ".Handle;\n"
+                             ).generate(sink, std::make_tuple(escape_keyword(param.param_name), escape_keyword(param.param_name), in_variable_name(param.param_name), escape_keyword(param.param_name)), context))
              return false;
            if (param.type.has_own && !as_generator(
                      escape_keyword(param.param_name) << ".SetOwn(false);\n"
@@ -736,10 +736,12 @@ struct convert_in_variable_generator
            attributes::complex_type_def const* complex = efl::eina::get<attributes::complex_type_def>(&param.type.original_type);
            if (!complex)
              return false;
-           auto var_name = in_variable_name(param.param_name);
            if (!as_generator(
-                 "var " << string << " = " << escape_keyword(param.param_name) << ".Handle;\n"
-              ).generate(sink, var_name, context))
+                             "Contract.Requires(" << string << " != null, nameof(" << string << "));\n"
+                             << "var " << string << " = " << string << ".Handle;\n"
+                             ).generate(sink, std::make_tuple(escape_keyword(param.param_name), escape_keyword(param.param_name),
+                                                         in_variable_name(param.param_name), escape_keyword(param.param_name))
+                                        , context))
              return false;
            if (param.type.has_own && !as_generator(
                      escape_keyword(param.param_name) << ".Own = false;\n"
@@ -777,8 +779,9 @@ struct convert_in_variable_generator
      else if (param.type.c_type == "Eina_Value")
        {
           return as_generator(
-                "var " << string << " = " << string << ".GetNative();\n"
-                  ).generate(sink, std::make_tuple(in_variable_name(param.param_name), param.param_name), context);
+                              "Contract.Requires(" << string << " != null, nameof(" << string << "));\n"
+                              "var " << string << " = " << string << ".GetNative();\n"
+                              ).generate(sink, std::make_tuple(param.param_name, param.param_name, in_variable_name(param.param_name), param.param_name), context);
        }
       return true;
    }

src/bin/eolian_mono/eolian_mono.cc

@@ -172,7 +172,8 @@ run(options_type const& opts)
                      "using System.Linq;\n"
                      "using System.Threading;\n"
                      "using System.ComponentModel;\n"
-                     "using System.Diagnostics.CodeAnalysis;\n")
+                     "using System.Diagnostics.CodeAnalysis;\n"
+                     "using System.Diagnostics.Contracts;\n")
      .generate(iterator, efl::eolian::grammar::attributes::unused, efl::eolian::grammar::context_null()))
      {
         throw std::runtime_error("Failed to generate file preamble");

src/tests/efl_mono/EinaTestData.cs

@@ -17,6 +17,7 @@ using System;
 using System.Linq;
 using System.Runtime.InteropServices;
 using System.Runtime.CompilerServices;
+using System.Diagnostics.Contracts;
 
 namespace EinaTestData
 {
@@ -95,6 +96,8 @@ public static class BaseData
         [ CallerLineNumber ] int line = 0,
         [ CallerFilePath ] string file = null,
         [ CallerMemberName ] string member = null) {
+        Contract.Requires(a != null, nameof(a));
+        Contract.Requires(b != null, nameof(b));
         Test.Assert(a.Length == b.Length, "Different lenght", line, file, member);
         for (int i = 0; i < a.Length; ++i)
         {