feat(devcontainer): log resolved feature install order and update test images

Author: prulloac

devcontainer/devcontainer.go

@@ -436,6 +436,16 @@ func (s *Spec) compileFeatures(fs billy.Filesystem, devcontainerDir, scratchDir
 		specsByRef[refRaw] = ef.spec
 	}
 	featureOrder, err := resolveInstallOrder(refRaws, specsByRef, idToRef, canonicalToRef, ambiguousCanonicals, s.OverrideFeatureInstallOrder)
+	// log the feature install order for debugging, since an error here is often due to an
+	// unexpected install order (e.g. due to a missing dependency that causes a cycle in the resolved graph).
+	if err == nil {
+		fmt.Printf("Resolved feature installation order:\n")
+		for i, refRaw := range featureOrder {
+			ef := extracted[refRaw]
+			fmt.Printf("%d: %s (ref %q, ID %q, version %q)\n", i+1, ef.spec.Name, refRaw, ef.spec.ID, ef.spec.Version)
+		}
+	}
+
 	if err != nil {
 		return "", nil, err
 	}

devcontainer/devcontainer_test.go

@@ -796,9 +796,7 @@ func TestCompileDevContainer(t *testing.T) {
 		t.Parallel()
 		fs := memfs.New()
 		dc := &devcontainer.Spec{
-			// Use scratch so UserFromDockerfile returns ("", nil) without
-			// any network access.
-			Image: "scratch",
+			Image: "localhost:5000/envbuilder-test-ubuntu:latest",
 		}
 		params, err := dc.Compile(fs, "", workingDir, "", "", false, stubLookupEnv)
 		require.NoError(t, err)
@@ -823,9 +821,7 @@ func TestCompileDevContainer(t *testing.T) {
 		require.NoError(t, err)
 		file, err := fs.OpenFile(filepath.Join(dcDir, "Dockerfile"), os.O_CREATE|os.O_WRONLY, 0o644)
 		require.NoError(t, err)
-		// Use scratch so UserFromDockerfile returns ("", nil) without any
-		// network access (the test only verifies build args and paths).
-		_, err = io.WriteString(file, "FROM scratch")
+		_, err = io.WriteString(file, "FROM localhost:5000/envbuilder-test-ubuntu:latest")
 		require.NoError(t, err)
 		_ = file.Close()
 		params, err := dc.Compile(fs, dcDir, workingDir, "", "/var/workspace", false, stubLookupEnv)