fix compiler unit tests, hook up daemon

internal/docker/image/image.go

@@ -4,7 +4,11 @@
 
 package image
 
-import "github.com/docker/distribution/reference"
+import (
+	"strings"
+
+	"github.com/docker/distribution/reference"
+)
 
 // Trim returns the short image name without tag.
 func Trim(name string) string {
@@ -69,3 +73,9 @@ func MatchHostname(image, hostname string) bool {
 	}
 	return reference.Domain(named) == hostname
 }
+
+// IsLatest parses the image and returns true if
+// the image uses the :latest tag.
+func IsLatest(s string) bool {
+	return strings.HasSuffix(Expand(s), ":latest")
+}

internal/docker/image/image_test.go

@@ -297,3 +297,41 @@ func Test_matchTag(t *testing.T) {
 		}
 	}
 }
+
+func Test_isLatest(t *testing.T) {
+	testdata := []struct {
+		name string
+		want bool
+	}{
+		{
+			name: "golang:1",
+			want: false,
+		},
+		{
+			name: "golang",
+			want: true,
+		},
+		{
+			name: "golang:latest",
+			want: true,
+		},
+		{
+			name: "docker.io/library/golang",
+			want: true,
+		},
+		{
+			name: "docker.io/library/golang:latest",
+			want: true,
+		},
+		{
+			name: "docker.io/library/golang:1",
+			want: false,
+		},
+	}
+	for _, test := range testdata {
+		got, want := IsLatest(test.name), test.want
+		if got != want {
+			t.Errorf("Want image %q isLatest %v", test.name, want)
+		}
+	}
+}