otkdistro: create test distro dynamically

Remove test/otk/fakedistro and instead create it when running the unit
test.  This will make it easier to evolve the test to cover more
features.

pkg/otkdistro/otkdistro_test.go

@@ -2,23 +2,104 @@ package otkdistro_test
 
 import (
 	"fmt"
+	"os"
+	"path/filepath"
 	"testing"
 
+	"gopkg.in/yaml.v3"
+
 	"github.com/osbuild/images/pkg/otkdistro"
 	"github.com/stretchr/testify/require"
 )
 
+func makeFakeDistro(root string) ([]string, error) {
+	arches := []string{
+		"aarch64",
+		"fakearch",
+		"x86_64",
+	}
+
+	imageTypes := []string{
+		"qcow2",
+		"container",
+	}
+
+	props := map[string]interface{}{
+		"name":            "FakeDistro",
+		"os_version":      "42.0",
+		"release_version": "42",
+		"runner":          "org.osbuild.fakedistro42",
+	}
+	propsfile, err := os.Create(filepath.Join(root, "properties.yaml"))
+	if err != nil {
+		return nil, fmt.Errorf("error creating properties file for test distro: %w", err)
+	}
+	if err := yaml.NewEncoder(propsfile).Encode(props); err != nil {
+		return nil, fmt.Errorf("error writing properties file for test distro: %w", err)
+	}
+
+	// make all otk files have the same content for now
+	otkcontent := map[string]interface{}{
+		"otk.version": "1",
+		"otk.target.osbuild.name": map[string]interface{}{
+			"pipelines": []map[string]interface{}{
+				{
+					"name": "build",
+					"stages": []map[string]interface{}{
+						{
+							"type":    "org.osbuild.rpm",
+							"options": nil,
+						},
+					},
+				},
+				{
+					"name": "os",
+					"stages": []map[string]interface{}{
+						{
+							"type":    "org.osbuild.rpm",
+							"options": nil,
+						},
+					},
+				},
+			},
+		},
+	}
+
+	expected := make([]string, 0, len(arches)*len(imageTypes))
+	for _, arch := range arches {
+		archpath := filepath.Join(root, arch)
+		if err := os.Mkdir(archpath, 0o777); err != nil {
+			return nil, fmt.Errorf("error creating architecture directory for test distro %q: %w", archpath, err)
+		}
+		for _, imageType := range imageTypes {
+			itpath := filepath.Join(archpath, imageType) + ".yaml"
+			itfile, err := os.Create(itpath)
+			if err != nil {
+				return nil, fmt.Errorf("error creating image type file for test distro %q: %w", itpath, err)
+			}
+			if err := yaml.NewEncoder(itfile).Encode(otkcontent); err != nil {
+				return nil, fmt.Errorf("error writing image type file for test distro %q: %w", itpath, err)
+			}
+			expected = append(expected, fmt.Sprintf("%s/%s", arch, imageType))
+		}
+	}
+
+	return expected, nil
+}
+
 func TestDistroLoad(t *testing.T) {
 	require := require.New(t)
 
-	// TODO: we can write the fragments during the test setup and make the
-	// whole test self-contained
-	distro, err := otkdistro.New("../../test/data/otk/fakedistro")
+	distroRoot := t.TempDir()
+	expected, err := makeFakeDistro(distroRoot)
+	require.NoError(err)
+
+	distro, err := otkdistro.New(distroRoot)
 	require.NoError(err)
 	require.Equal("FakeDistro", distro.Name())
 	require.Equal("42.0", distro.OsVersion())
 	require.Equal("42", distro.Releasever())
-	// TODO: check runner when it's added
+	// TODO: check runner when it's added to the distro interface
 
 	archImageTypes := make([]string, 0)
 	for _, archName := range distro.ListArches() {
@@ -30,11 +111,5 @@ func TestDistroLoad(t *testing.T) {
 		}
 	}
 
-	expected := []string{
-		"aarch64/qcow2",
-		"fakearch/qcow2",
-		"x86_64/qcow2",
-	}
-
 	require.ElementsMatch(expected, archImageTypes)
 }