tests/environment: reproduce bug between GC and cabi_realloc for wasmimport functions

Working on #348.

Author: ydnar

tests/environment/big.txt

@@ -0,0 +1,51 @@
+package environment_test
+
+import (
+	"flag"
+	"os"
+	"testing"
+	"unsafe"
+
+	"tests/generated/wasi/cli/v0.2.0/environment"
+)
+
+func TestEnvironment(t *testing.T) {
+	env := environment.GetEnvironment()
+	t.Logf("env len: %d", env.Len())
+	for i, kv := range env.Slice() {
+		t.Logf("%02d: %s = %s", i, truncate(kv[0], 32), truncate(kv[1], 32))
+	}
+}
+
+var bigArg = flag.String("big", "", "big argument")
+
+func TestArguments(t *testing.T) {
+	args := environment.GetArguments().Slice()
+
+	// t.Errorf("os.Args: %v\nargs: %v", os.Args, args)
+	t.Errorf("os.Args: %v", unsafe.SliceData(os.Args))
+	t.Errorf("os.Args[0]: %v", unsafe.StringData(os.Args[0]))
+	t.Errorf("len(os.Args): %d", len(os.Args))
+	t.Errorf("os.Args[1]: %s", os.Args[1])
+
+	for i, arg := range args {
+		t.Logf("%02d: %s", i, truncate(arg, 64))
+		if !testing.Verbose() && arg == "-test.v" {
+			t.Errorf("testing.Verbose() == false with %s arg", arg)
+		}
+	}
+
+	for i := 0; i < 1000; i++ {
+		args2 := environment.GetArguments().Slice()
+		if want, got := len(args), len(args2); got != want {
+			t.Errorf("len(args2): %d, expected %d", got, want)
+		}
+	}
+}
+
+func truncate(s string, n int) string {
+	if len(s) > n {
+		s = s[:n] + "…"
+	}
+	return s
+}