Give priority to variables declared later.

Author: utam0k

pkg/dazzle/combiner.go

@@ -319,13 +319,19 @@ func mergeEnv(base *ociv1.Image, others []*ociv1.Image, vars []EnvVarCombination
 						vss []string
 						idx = make(map[string]struct{})
 					)
-					for _, v := range vs {
+					lenVS := len(vs) - 1
+					for i := range vs {
+						v := vs[lenVS-i]
 						if _, exists := idx[v]; exists {
 							continue
 						}
 						idx[v] = struct{}{}
 						vss = append(vss, v)
 					}
+
+					for i, j := 0, len(vss)-1; i < j; i, j = i+1, j-1 {
+						vss[i], vss[j] = vss[j], vss[i]
+					}
 					envs[k] = strings.Join(vss, ":")
 				}
 				log.WithFields(log.Fields{

pkg/dazzle/combiner_test.go

@@ -62,7 +62,7 @@ func TestMergeEnv(t *testing.T) {
 				{
 					Config: ociv1.ImageConfig{
 						Env: []string{
-							"PATH=seventh:eighth:seventh:common-value",
+							"PATH=eighth:seventh:eighth:common-value",
 						},
 					},
 				},
@@ -73,7 +73,7 @@ func TestMergeEnv(t *testing.T) {
 					Action: EnvVarCombineMergeUnique,
 				},
 			},
-			expect: []string{"PATH=first:second:third:common-value:fourth:fifth:sixth:seventh:eighth"},
+			expect: []string{"PATH=first:second:third:fourth:fifth:sixth:seventh:eighth:common-value"},
 		},
 		{
 			name: "EnvVarCombineMerge",