package beside

import (
	"fmt"
	"os"
	"path/filepath"
	"testing"
)

// The captured copy of a repository is laid out once per test process: a second call, in another test,
// gets the same directory (issue 1379, AC3). Laying it out per test made go/catalogue's tests take 2.14 s
// against the unit level's 2 s bound; once, 0.81 s.
func TestTheCapturedCopyIsLaidOutOnce(t *testing.T) {
	t.Setenv(Env, "")
	var first, second string
	t.Run("one", func(t *testing.T) { first = Dir(t, "mesh-catalog") })
	t.Run("two", func(t *testing.T) { second = Dir(t, "mesh-catalog") })
	if first == "" || first != second {
		t.Fatalf("the captured copy was laid out twice: %q and %q", first, second)
	}
	if _, err := os.Stat(filepath.Join(first, "modules")); err != nil {
		t.Fatalf("the copy holds no modules directory: %v", err)
	}
	// And it outlives the test that first asked, which a t.TempDir would not.
	if _, err := os.Stat(first); err != nil {
		t.Fatalf("the copy is gone after the first test ended: %v", err)
	}
}

// With MESH_CHECK_BESIDE naming a directory that lacks the repository, the test fails naming it (AC4; the
// rule is beside's own, unchanged). Dir fails the test it is given, so it is given a recorder.
func TestABesideDirectoryWithoutTheRepositoryFailsNamingIt(t *testing.T) {
	empty := t.TempDir()
	t.Setenv(Env, empty)
	r := &recorder{TB: t}
	func() {
		defer func() { _ = recover() }()
		Dir(r, "mesh-catalog")
	}()
	if !r.failed {
		t.Fatal("a repository missing beside the check did not fail the test")
	}
	if want := "mesh-catalog is not beside this check in " + Env + "=" + empty; len(r.msg) < len(want) || r.msg[:len(want)] != want {
		t.Fatalf("the failure does not name the repository and the directory: %q", r.msg)
	}
}

type recorder struct {
	testing.TB
	failed bool
	msg    string
}

func (r *recorder) Fatalf(format string, args ...any) {
	r.failed = true
	r.msg = sprintf(format, args...)
	panic(stop{})
}

type stop struct{}

func sprintf(format string, args ...any) string { return fmt.Sprintf(format, args...) }