container/stub: export stub helpers

These are very useful in many packages containing relatively large amount of code making calls to difficult or impossible to stub functions.

Signed-off-by: Ophestra <cat@gensokyo.uk>

container/stub/exit_test.go

@@ -0,0 +1,30 @@
+package stub_test
+
+import (
+	"testing"
+
+	"hakurei.app/container/stub"
+)
+
+func TestHandleExit(t *testing.T) {
+	t.Run("exit", func(t *testing.T) {
+		defer stub.HandleExit()
+		panic(stub.PanicExit)
+	})
+
+	t.Run("nil", func(t *testing.T) {
+		defer stub.HandleExit()
+	})
+
+	t.Run("passthrough", func(t *testing.T) {
+		defer func() {
+			want := 0xcafebabe
+			if r := recover(); r != want {
+				t.Errorf("recover: %v, want %v", r, want)
+			}
+
+		}()
+		defer stub.HandleExit()
+		panic(0xcafebabe)
+	})
+}