Cross-Platform Crucible (#2)

Crucible groundwork for cross-platform compatibility.

Reviewed-on: #2
Reviewed-by: xtul <mpiasecki720@protonmail.com>
Co-authored-by: vickydotbat <vickydotbat@tutamail.com>
Co-committed-by: vickydotbat <vickydotbat@tutamail.com>

internal/menu/menu_test.go

@@ -0,0 +1,47 @@
+package menu
+
+import (
+	"io"
+	"reflect"
+	"strings"
+	"testing"
+)
+
+var sample = []Item{
+	{Label: "module build", Desc: "build the .mod", Args: []string{"module", "build"}},
+	{Label: "topdata validate-topdata", Desc: "validate topdata", Args: []string{"topdata", "validate-topdata"}},
+}
+
+func TestSelectReturnsChosenArgs(t *testing.T) {
+	got, err := Select(io.Discard, strings.NewReader("1\n\n"), sample)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if want := []string{"module", "build"}; !reflect.DeepEqual(got, want) {
+		t.Fatalf("got %v, want %v", got, want)
+	}
+}
+
+func TestSelectAppendsExtraArgs(t *testing.T) {
+	got, err := Select(io.Discard, strings.NewReader("2\n--dry-run foo\n"), sample)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	want := []string{"topdata", "validate-topdata", "--dry-run", "foo"}
+	if !reflect.DeepEqual(got, want) {
+		t.Fatalf("got %v, want %v", got, want)
+	}
+}
+
+func TestSelectQuitReturnsNil(t *testing.T) {
+	got, err := Select(io.Discard, strings.NewReader("q\n"), sample)
+	if err != nil || got != nil {
+		t.Fatalf("quit should return (nil,nil); got (%v,%v)", got, err)
+	}
+}
+
+func TestSelectInvalidErrors(t *testing.T) {
+	if _, err := Select(io.Discard, strings.NewReader("99\n"), sample); err == nil {
+		t.Fatal("out-of-range selection should error")
+	}
+}