Add Extern autodoc test

src/extern.zig

@@ -72,12 +72,47 @@ pub const Extern = extern struct {
     extern "c" fn wasmtime_extern_type(*const Store.Context, *const Extern) *ExternType;
 };
 
-// pub const ExternVec = Vec(*Extern, wasm_extern_vec_new_empty, wasm_extern_vec_new_uninitialized, wasm_extern_vec_new, wasm_extern_vec_copy, wasm_extern_vec_delete);
-// extern "c" fn wasm_extern_vec_new_empty(*anyopaque, usize) void;
-// extern "c" fn wasm_extern_vec_new_uninitialized(*anyopaque, usize) void;
-// extern "c" fn wasm_extern_vec_new(*anyopaque, usize, [*]const ?*Extern) void;
-// extern "c" fn wasm_extern_vec_copy(*anyopaque, *const anyopaque) void;
-// extern "c" fn wasm_extern_vec_delete(*anyopaque) void;
+test Extern {
+    const std = @import("std");
+    const expect = std.testing.expect;
+
+    const wasm = @import("./main.zig");
+
+    const wat_bytes =
+        \\(module
+        \\  (func (export "some_function"))
+        \\  (global (export "some_global") (mut i32) (i32.const 0))
+        \\  (memory (export "some_memory") 1)
+        \\)
+    ;
+
+    // If an error *does* occur, settings up Diagnostics with debug_print will
+    // make sure that the error will actually be visible in the test log.
+    var diag = try wasm.Diagnostics.init(std.testing.allocator, true);
+    defer diag.deinit();
+
+    var engine = try wasm.Engine.initDefault();
+    defer engine.deinit();
+    var module = try wasm.Module.initFromWat(engine, wat_bytes, diag);
+    defer module.deinit();
+    var store = wasm.Store.init(engine);
+    defer store.deinit();
+    var context = store.getContext();
+
+    var instance = try wasm.Instance.init(context, module, &.{}, null);
+
+    const some_function = try instance.getByIndex(context, 0, wasm.Func);
+    const some_global = try instance.getByIndex(context, 1, wasm.Global);
+    const some_memory = try instance.getByIndex(context, 2, wasm.Memory);
+
+    try expect(std.mem.eql(u8, some_function.name, "some_function"));
+    try expect(std.mem.eql(u8, some_global.name, "some_global"));
+    try expect(std.mem.eql(u8, some_memory.name, "some_memory"));
+
+    try expect(instance.getByIndex(context, 3, wasm.Func) == error.ExportNotFound);
+    try expect(instance.get(context, "no_such_func", wasm.Func) == error.ExportNotFound);
+    try expect(instance.get(context, "some_function", wasm.Global) == error.IncorrectType);
+}
 
 pub const ExternType = opaque {
     pub fn copy(self: *const ExternType) *ExternType {
@@ -132,10 +167,3 @@ pub const ExternType = opaque {
     // extern "c" fn wasm_externtype_as_globaltype_const(*const ExternType) ?*const GlobalType;
     extern "c" fn wasm_externtype_as_memorytype_const(*const ExternType) ?*const MemoryType;
 };
-
-// pub const ExternTypeVec = Vec(*ExternType, wasm_externtype_vec_new_empty, wasm_externtype_vec_new_uninitialized, wasm_externtype_vec_new, wasm_externtype_vec_copy, wasm_externtype_vec_delete);
-// extern "c" fn wasm_externtype_vec_new_empty(*anyopaque, usize) void;
-// extern "c" fn wasm_externtype_vec_new_uninitialized(*anyopaque, usize) void;
-// extern "c" fn wasm_externtype_vec_new(*anyopaque, usize, [*]const ?*ExternType) void;
-// extern "c" fn wasm_externtype_vec_copy(*anyopaque, *const anyopaque) void;
-// extern "c" fn wasm_externtype_vec_delete(*anyopaque) void;