Refactor compiler and annotate buildoptions into compiler metadata

This allows to later pick up values used during build of each package

pkg/compiler/backend_test.go

@@ -0,0 +1,78 @@
+// Copyright © 2019 Ettore Di Giacinto <mudler@gentoo.org>
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 2 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this program; if not, see <http://www.gnu.org/licenses/>.
+
+package compiler_test
+
+import (
+	. "github.com/mudler/luet/pkg/compiler"
+	. "github.com/mudler/luet/pkg/compiler/backend"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("Docker image diffs", func() {
+	var b CompilerBackend
+
+	BeforeEach(func() {
+		b = NewSimpleDockerBackend()
+	})
+
+	Context("Generate diffs from docker images", func() {
+		It("Detect no changes", func() {
+			opts := Options{
+				ImageName: "alpine:latest",
+			}
+			err := b.DownloadImage(opts)
+			Expect(err).ToNot(HaveOccurred())
+
+			layers, err := GenerateChanges(b, opts, opts)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(len(layers)).To(Equal(1))
+			Expect(len(layers[0].Diffs.Additions)).To(Equal(0))
+			Expect(len(layers[0].Diffs.Changes)).To(Equal(0))
+			Expect(len(layers[0].Diffs.Deletions)).To(Equal(0))
+		})
+
+		It("Detects additions and changed files", func() {
+			err := b.DownloadImage(Options{
+				ImageName: "quay.io/mocaccino/micro",
+			})
+			Expect(err).ToNot(HaveOccurred())
+			err = b.DownloadImage(Options{
+				ImageName: "quay.io/mocaccino/extra",
+			})
+			Expect(err).ToNot(HaveOccurred())
+
+			layers, err := GenerateChanges(b, Options{
+				ImageName: "quay.io/mocaccino/micro",
+			}, Options{
+				ImageName: "quay.io/mocaccino/extra",
+			})
+			Expect(err).ToNot(HaveOccurred())
+			Expect(len(layers)).To(Equal(1))
+
+			Expect(len(layers[0].Diffs.Changes) > 0).To(BeTrue())
+			Expect(len(layers[0].Diffs.Changes[0].Name) > 0).To(BeTrue())
+			Expect(layers[0].Diffs.Changes[0].Size > 0).To(BeTrue())
+
+			Expect(len(layers[0].Diffs.Additions) > 0).To(BeTrue())
+			Expect(len(layers[0].Diffs.Additions[0].Name) > 0).To(BeTrue())
+			Expect(layers[0].Diffs.Additions[0].Size > 0).To(BeTrue())
+
+			Expect(len(layers[0].Diffs.Deletions)).To(Equal(0))
+		})
+	})
+})