Fixed equality check in package comparison

Author: cftorres

tests/multi_diff_expected.json

@@ -115,36 +115,6 @@
               "Size": 73348
             }
           ]
-        },
-        {
-          "Package": "setuptools",
-          "Info1": [
-            {
-              "Version": "36.2.2",
-              "Size": 839895
-            }
-          ],
-          "Info2": [
-            {
-              "Version": "36.2.2",
-              "Size": 1157078
-            }
-          ]
-        },
-        {
-          "Package": "wheel",
-          "Info1": [
-            {
-              "Version": "0.29.0",
-              "Size": 103509
-            }
-          ],
-          "Info2": [
-            {
-              "Version": "0.29.0",
-              "Size": 137451
-            }
-          ]
         }
       ]
     }

utils/package_diff_utils.go

@@ -129,29 +129,36 @@ func diffMaps(map1, map2 interface{}) interface{} {
 	for _, pack := range map1Value.MapKeys() {
 		packageEntry1 := map1Value.MapIndex(pack)
 		packageEntry2 := map2Value.MapIndex(pack)
+		// If the package does not exist in Image2's map of packages, add it to the collection of unique packages in Image1
 		if !packageEntry2.IsValid() {
 			diff1.SetMapIndex(pack, packageEntry1)
+			// If the package exists in Image2's map of packages but the package information differs between images, add it to
+			// the difference.  Otherwise, if the information is consistent across images, delete it from the Image2's map of packages.
 		} else {
 			if multiV {
 				if !reflect.DeepEqual(packageEntry2.Interface(), packageEntry1.Interface()) {
 					multiInfoDiff = multiVersionDiff(multiInfoDiff, pack.String(),
-							packageEntry1.Interface().(map[string]PackageInfo),
-							packageEntry2.Interface().(map[string]PackageInfo))
+						packageEntry1.Interface().(map[string]PackageInfo),
+						packageEntry2.Interface().(map[string]PackageInfo))
 				}
 			} else {
 				packageInfo1 := packageEntry1.Interface().(PackageInfo)
 				packageInfo2 := packageEntry2.Interface().(PackageInfo)
-				if packageInfo2.Version != packageInfo2.Version {
+				// If two instances of the same package don't have the same version, then they are considered to be different
+				if packageInfo1.Version != packageInfo2.Version {
 					infoDiff = append(infoDiff, Info{pack.String(), packageInfo1, packageInfo2})
 				}
 			}
 			map2Value.SetMapIndex(pack, reflect.Value{})
 		}
 	}
+
+	// The packages remaining in Image2's map of images are those that exist uniquely in Image2
 	for _, key2 := range map2Value.MapKeys() {
 		packageEntry2 := map2Value.MapIndex(key2)
 		diff2.SetMapIndex(key2, packageEntry2)
 	}
+
 	if multiV {
 		return MultiVersionPackageDiff{Packages1: diff1.Interface().(map[string]map[string]PackageInfo),
 			Packages2: diff2.Interface().(map[string]map[string]PackageInfo), InfoDiff: multiInfoDiff}

utils/package_diff_utils_test.go

@@ -60,7 +60,6 @@ func TestDiffMaps(t *testing.T) {
 				Packages1: map[string]PackageInfo{},
 				Packages2: map[string]PackageInfo{},
 				InfoDiff: []Info{
-					{"pac2", PackageInfo{"2.0", 50}, PackageInfo{"2.0", 45}},
 					{"pac3", PackageInfo{"3.0", 60}, PackageInfo{"4.0", 60}}},
 			},
 		},
@@ -141,7 +140,7 @@ func TestDiffMaps(t *testing.T) {
 			sort.Sort(ByPackage(expected.InfoDiff))
 			sort.Sort(ByPackage(actual.InfoDiff))
 			if !reflect.DeepEqual(expected, actual) {
-				t.Errorf("expected Diff to be: %s but got:%s", expected, actual)
+				t.Errorf("expected Diff to be: %v but got:%v", expected, actual)
 				return
 			}
 		case MultiVersionPackageDiff:
@@ -158,7 +157,7 @@ func TestDiffMaps(t *testing.T) {
 				sort.Sort(ByPackageInfo(pack2.Info2))
 			}
 			if !reflect.DeepEqual(expected, actual) {
-				t.Errorf("expected Diff to be: %s but got:%s", expected, actual)
+				t.Errorf("expected Diff to be: %v but got:%v", expected, actual)
 				return
 			}
 		}