osbuild/copy: support files input

Add support for files input in the copy stage. This will enable copying
inline sources as a custom files in the image filesystem tree.

Add a simple unit test covering the use of this stage input.

Signed-off-by: Tomáš Hozza <thozza@redhat.com>

internal/osbuild/copy_stage.go

@@ -39,6 +39,10 @@ func NewCopyStageSimple(options *CopyStageOptions, inputs Inputs) *Stage {
 	}
 }
 
+type CopyStageFilesInputs map[string]*FilesInput
+
+func (*CopyStageFilesInputs) isStageInputs() {}
+
 // GenCopyFSTreeOptions creates the options, inputs, devices, and mounts properties
 // for an org.osbuild.copy stage for a given source tree using a partition
 // table description to define the mounts

internal/osbuild/copy_stage_test.go

@@ -1,6 +1,7 @@
 package osbuild
 
 import (
+	"fmt"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -43,3 +44,28 @@ func TestNewCopyStage(t *testing.T) {
 	actualStage := NewCopyStage(&CopyStageOptions{paths}, NewPipelineTreeInputs("tree-input", "input-pipeline"), &stageDevices, &stageMounts)
 	assert.Equal(t, expectedStage, actualStage)
 }
+
+func TestNewCopyStageSimpleSourcesInputs(t *testing.T) {
+	fileSum := "1234567890abcdef1234567890abcdef1234567890abcdef1234567890abcdef"
+
+	paths := []CopyStagePath{
+		{
+			From: fmt.Sprintf("input://inlinefile/sha256:%x", fileSum),
+			To:   "tree://etc/inlinefile",
+		},
+	}
+
+	filesInputs := CopyStageFilesInputs{
+		"inlinefile": NewFilesInput(NewFilesInputSourceArrayRef([]FilesInputSourceArrayRefEntry{
+			NewFilesInputSourceArrayRefEntry(fileSum, nil),
+		})),
+	}
+
+	expectedStage := &Stage{
+		Type:    "org.osbuild.copy",
+		Options: &CopyStageOptions{paths},
+		Inputs:  &filesInputs,
+	}
+	actualStage := NewCopyStageSimple(&CopyStageOptions{paths}, &filesInputs)
+	assert.Equal(t, expectedStage, actualStage)
+}