Add a wasmtime-specific wasmtime_wat2wasm C API (#1206)

* Add a wasmtime-specific `wasmtime_wat2wasm` C API

This commit implements a wasmtime-specific C API for converting the text
format to the binary format. An upstream spec issue exists for adding
this to the C API, but in the meantime we can experiment with our own
version of this API and use it in the C# extension, for example!

Closes #1000

* Reorder arguments

* Use wasm_byte_vec_t for input `*.wat`

* Mark wat input as const

* Return an error message and use `fixed`

* Actually include the error message

* Use `fixed` in `Module.cs` as well

crates/misc/dotnet/tests/Fixtures/ModuleFixture.cs

@@ -13,7 +13,9 @@ namespace Wasmtime.Tests
                 .WithReferenceTypes(true)
                 .Build();
             Store = Engine.CreateStore();
-            Module = Store.CreateModule(Path.Combine("Modules", ModuleFileName));
+            var wat = Path.Combine("Modules", ModuleFileName);
+            var wasm = Engine.WatToWasm(File.ReadAllText(wat));
+            Module = Store.CreateModule(wat, wasm);
         }
 
         public void Dispose()

crates/misc/dotnet/tests/FunctionExportsTests.cs

@@ -8,7 +8,7 @@ namespace Wasmtime.Tests
 {
     public class FunctionExportsFixture : ModuleFixture
     {
-        protected override string ModuleFileName => "FunctionExports.wasm";
+        protected override string ModuleFileName => "FunctionExports.wat";
     }
 
     public class FunctionExportsTests : IClassFixture<FunctionExportsFixture>

crates/misc/dotnet/tests/FunctionImportsTests.cs

@@ -8,7 +8,7 @@ namespace Wasmtime.Tests
 {
     public class FunctionImportsFixture : ModuleFixture
     {
-        protected override string ModuleFileName => "FunctionImports.wasm";
+        protected override string ModuleFileName => "FunctionImports.wat";
     }
 
     public class FunctionImportsTests : IClassFixture<FunctionImportsFixture>

crates/misc/dotnet/tests/FunctionThunkingTests.cs

@@ -7,7 +7,7 @@ namespace Wasmtime.Tests
 {
     public class FunctionThunkingFixture : ModuleFixture
     {
-        protected override string ModuleFileName => "FunctionThunking.wasm";
+        protected override string ModuleFileName => "FunctionThunking.wat";
     }
 
     public class FunctionThunkingTests : IClassFixture<FunctionThunkingFixture>

crates/misc/dotnet/tests/GlobalExportsTests.cs

@@ -10,7 +10,7 @@ namespace Wasmtime.Tests
 {
     public class GlobalExportsFixture : ModuleFixture
     {
-        protected override string ModuleFileName => "GlobalExports.wasm";
+        protected override string ModuleFileName => "GlobalExports.wat";
     }
 
     public class GlobalExportsTests : IClassFixture<GlobalExportsFixture>

crates/misc/dotnet/tests/GlobalImportBindingTests.cs

@@ -6,7 +6,7 @@ namespace Wasmtime.Tests
 {
     public class GlobalImportBindingFixture : ModuleFixture
     {
-        protected override string ModuleFileName => "GlobalImportBindings.wasm";
+        protected override string ModuleFileName => "GlobalImportBindings.wat";
     }
 
     public class GlobalImportBindingTests : IClassFixture<GlobalImportBindingFixture>

crates/misc/dotnet/tests/GlobalImportsTests.cs

@@ -8,7 +8,7 @@ namespace Wasmtime.Tests
 {
     public class GlobalImportsFixture : ModuleFixture
     {
-        protected override string ModuleFileName => "GlobalImports.wasm";
+        protected override string ModuleFileName => "GlobalImports.wat";
     }
 
     public class GlobalImportsTests : IClassFixture<GlobalImportsFixture>

crates/misc/dotnet/tests/MemoryExportsTests.cs

@@ -8,7 +8,7 @@ namespace Wasmtime.Tests
 {
     public class MemoryExportsFixture : ModuleFixture
     {
-        protected override string ModuleFileName => "MemoryExports.wasm";
+        protected override string ModuleFileName => "MemoryExports.wat";
     }
 
     public class MemoryExportsTests : IClassFixture<MemoryExportsFixture>

crates/misc/dotnet/tests/MemoryImportBindingTests.cs

@@ -6,7 +6,7 @@ namespace Wasmtime.Tests
 {
     public class MemoryImportBindingFixture : ModuleFixture
     {
-        protected override string ModuleFileName => "MemoryImportBinding.wasm";
+        protected override string ModuleFileName => "MemoryImportBinding.wat";
     }
 
     public class MemoryImportBindingTests : IClassFixture<MemoryImportBindingFixture>

crates/misc/dotnet/tests/MemoryImportFromModuleTests.cs

@@ -6,7 +6,7 @@ namespace Wasmtime.Tests
 {
     public class MemoryImportFromModuleFixture : ModuleFixture
     {
-        protected override string ModuleFileName => "MemoryImportFromModule.wasm";
+        protected override string ModuleFileName => "MemoryImportFromModule.wat";
     }
 
     public class MemoryImportFromModuleTests : IClassFixture<MemoryImportFromModuleFixture>

crates/misc/dotnet/tests/MemoryImportNoUpperBoundTests.cs

@@ -6,7 +6,7 @@ namespace Wasmtime.Tests
 {
     public class MemoryImportNoUpperBoundFixture : ModuleFixture
     {
-        protected override string ModuleFileName => "MemoryImportNoUpperBound.wasm";
+        protected override string ModuleFileName => "MemoryImportNoUpperBound.wat";
     }
 
     public class MemoryImportNoUpperBoundTests : IClassFixture<MemoryImportNoUpperBoundFixture>

crates/misc/dotnet/tests/MemoryImportWithUpperBoundTests.cs

@@ -6,7 +6,7 @@ namespace Wasmtime.Tests
 {
     public class MemoryImportWithUpperBoundFixture : ModuleFixture
     {
-        protected override string ModuleFileName => "MemoryImportWithUpperBound.wasm";
+        protected override string ModuleFileName => "MemoryImportWithUpperBound.wat";
     }
 
     public class MemoryImportWithUpperBoundTests : IClassFixture<MemoryImportWithUpperBoundFixture>

crates/misc/dotnet/tests/TableExportsTests.cs

@@ -8,7 +8,7 @@ namespace Wasmtime.Tests
 {
     public class TableExportsFixture : ModuleFixture
     {
-        protected override string ModuleFileName => "TableExports.wasm";
+        protected override string ModuleFileName => "TableExports.wat";
     }
 
     public class TableExportsTests : IClassFixture<TableExportsFixture>

crates/misc/dotnet/tests/TableImportsTests.cs

@@ -8,7 +8,7 @@ namespace Wasmtime.Tests
 {
     public class TableImportsFixture : ModuleFixture
     {
-        protected override string ModuleFileName => "TableImports.wasm";
+        protected override string ModuleFileName => "TableImports.wat";
     }
 
     public class TableImportsTests : IClassFixture<TableImportsFixture>

crates/misc/dotnet/tests/TempFile.cs

@@ -21,4 +21,4 @@ namespace Wasmtime.Tests
 
         public string Path { get; private set; }
     }
-}
+}

crates/misc/dotnet/tests/WasiTests.cs

@@ -9,7 +9,7 @@ namespace Wasmtime.Tests
 {
     public class WasiFixture : ModuleFixture
     {
-        protected override string ModuleFileName => "Wasi.wasm";
+        protected override string ModuleFileName => "Wasi.wat";
     }
 
     public class WasiTests : IClassFixture<WasiFixture>

crates/misc/dotnet/tests/Wasmtime.Tests.csproj

@@ -27,7 +27,7 @@
   </Target>
 
   <ItemGroup>
-    <None Update="Modules/*.wasm" CopyToOutputDirectory="PreserveNewest" />
+    <None Update="Modules/*.wat" CopyToOutputDirectory="PreserveNewest" />
   </ItemGroup>
 
 </Project>