move golang tests to its own directory

this prepares for more test binaries.

test/go/BUILD

@@ -0,0 +1,23 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library", "go_test")
+load("//rules:rules_go.bzl", "go_binary")
+
+go_library(
+    name = "go_lib",
+    srcs = ["hello.go"],
+    cgo = True,
+    importpath = "git.sr.ht/~motiejus/bazel-zig-cc/test/go",
+    visibility = ["//visibility:private"],
+)
+
+go_binary(
+    name = "go",
+    embed = [":go_lib"],
+    static = "on",
+    visibility = ["//visibility:public"],
+)
+
+go_test(
+    name = "go_test",
+    srcs = ["hello_test.go"],
+    embed = [":go_lib"],
+)

test/go/hello.go

@@ -0,0 +1,14 @@
+package main
+
+// #include <stdio.h>
+// char* hello() { return "hello, world"; }
+// void printhello() { printf("%s\n", hello()); }
+import "C"
+
+func main() {
+	C.printhello()
+}
+
+func Chello() string {
+	return C.GoString(C.hello())
+}

test/go/hello_test.go

@@ -0,0 +1,13 @@
+package main
+
+import (
+	"testing"
+)
+
+func TestHello(t *testing.T) {
+	want := "hello, world"
+	got := Chello()
+	if got != want {
+		t.Errorf("expected %q, got %q", want, got)
+	}
+}