fix: Make testutil.AssertEqual more like testify

- Swap actual and expected arguments
- Add optional Sprintf arguments
- Add messages to existing usages

pkg/apply/applier_test.go

@@ -1258,7 +1258,9 @@ func TestApplier(t *testing.T) {
 			sort.Sort(testutil.GroupedEventsByID(receivedEvents))
 
 			// Validate the rest of the events
-			testutil.AssertEqual(t, receivedEvents, tc.expectedEvents)
+			testutil.AssertEqual(t, tc.expectedEvents, receivedEvents,
+				"Actual events (%d) do not match expected events (%d)",
+				len(receivedEvents), len(tc.expectedEvents))
 
 			// Validate that the expected timeout was the cause of the run completion.
 			// just in case something else cancelled the run
@@ -1690,7 +1692,9 @@ func TestApplierCancel(t *testing.T) {
 			}
 
 			// Validate the rest of the events
-			testutil.AssertEqual(t, receivedEvents, tc.expectedEvents)
+			testutil.AssertEqual(t, tc.expectedEvents, receivedEvents,
+				"Actual events (%d) do not match expected events (%d)",
+				len(receivedEvents), len(tc.expectedEvents))
 
 			// Validate that the expected timeout was the cause of the run completion.
 			// just in case something else cancelled the run
@@ -1819,8 +1823,13 @@ func TestReadAndPrepareObjects(t *testing.T) {
 			}
 			require.NoError(t, err)
 
-			testutil.AssertEqual(t, tc.applyObjs, applyObjs)
-			testutil.AssertEqual(t, tc.pruneObjs, pruneObjs)
+			testutil.AssertEqual(t, applyObjs, tc.applyObjs,
+				"Actual applied objects (%d) do not match expected applied objects (%d)",
+				len(applyObjs), len(tc.applyObjs))
+
+			testutil.AssertEqual(t, pruneObjs, tc.pruneObjs,
+				"Actual pruned objects (%d) do not match expected pruned objects (%d)",
+				len(pruneObjs), len(tc.pruneObjs))
 		})
 	}
 }

pkg/apply/destroyer_test.go

@@ -375,7 +375,9 @@ func TestDestroyerCancel(t *testing.T) {
 			}
 
 			// Validate the rest of the events
-			testutil.AssertEqual(t, receivedEvents, tc.expectedEvents)
+			testutil.AssertEqual(t, tc.expectedEvents, receivedEvents,
+				"Actual events (%d) do not match expected events (%d)",
+				len(receivedEvents), len(tc.expectedEvents))
 
 			// Validate that the expected timeout was the cause of the run completion.
 			// just in case something else cancelled the run

pkg/apply/task/inv_set_task_test.go

@@ -232,7 +232,9 @@ func TestInvSetTask(t *testing.T) {
 				t.Errorf("unexpected error running InvAddTask: %s", result.Err)
 			}
 			actual, _ := client.GetClusterObjs(nil, common.DryRunNone)
-			testutil.AssertEqual(t, actual, tc.expectedObjs)
+			testutil.AssertEqual(t, tc.expectedObjs, actual,
+				"Actual cluster objects (%d) do not match expected cluster objects (%d)",
+				len(actual), len(tc.expectedObjs))
 		})
 	}
 }

pkg/apply/taskrunner/task_test.go

@@ -202,7 +202,9 @@ loop:
 			},
 		},
 	}
-	testutil.AssertEqual(t, receivedEvents, expectedEvents)
+	testutil.AssertEqual(t, expectedEvents, receivedEvents,
+		"Actual events (%d) do not match expected events (%d)",
+		len(receivedEvents), len(expectedEvents))
 }
 
 func TestWaitTask_Timeout(t *testing.T) {
@@ -327,7 +329,9 @@ loop:
 			},
 		},
 	}
-	testutil.AssertEqual(t, receivedEvents, expectedEvents)
+	testutil.AssertEqual(t, expectedEvents, receivedEvents,
+		"Actual events (%d) do not match expected events (%d)",
+		len(receivedEvents), len(expectedEvents))
 }
 
 func TestWaitTask_StartAndComplete(t *testing.T) {
@@ -390,7 +394,9 @@ loop:
 			},
 		},
 	}
-	testutil.AssertEqual(t, receivedEvents, expectedEvents)
+	testutil.AssertEqual(t, expectedEvents, receivedEvents,
+		"Actual events (%d) do not match expected events (%d)",
+		len(receivedEvents), len(expectedEvents))
 }
 
 func TestWaitTask_Cancel(t *testing.T) {
@@ -450,7 +456,9 @@ loop:
 			},
 		},
 	}
-	testutil.AssertEqual(t, receivedEvents, expectedEvents)
+	testutil.AssertEqual(t, expectedEvents, receivedEvents,
+		"Actual events (%d) do not match expected events (%d)",
+		len(receivedEvents), len(expectedEvents))
 }
 
 func TestWaitTask_SingleTaskResult(t *testing.T) {
@@ -531,7 +539,9 @@ loop:
 			},
 		},
 	}
-	testutil.AssertEqual(t, receivedEvents, expectedEvents)
+	testutil.AssertEqual(t, expectedEvents, receivedEvents,
+		"Actual events (%d) do not match expected events (%d)",
+		len(receivedEvents), len(expectedEvents))
 
 	expectedResults := []TaskResult{
 		{}, // Empty result means success

pkg/testutil/matcher.go

@@ -14,6 +14,7 @@ import (
 	"github.com/google/go-cmp/cmp"
 	"github.com/google/go-cmp/cmp/cmpopts"
 	"github.com/onsi/gomega/format"
+	"github.com/stretchr/testify/assert"
 )
 
 // Equal returns a matcher for use with Gomega that uses go-cmp's cmp.Equal to
@@ -31,21 +32,21 @@ type cmpMatcher struct {
 }
 
 func (cm *cmpMatcher) Match(actual interface{}) (bool, error) {
-	match := cmp.Equal(actual, cm.expected, cmpopts.EquateErrors())
+	match := cmp.Equal(cm.expected, actual, cmpopts.EquateErrors())
 	if !match {
-		cm.explanation = errors.New(cmp.Diff(actual, cm.expected, cmpopts.EquateErrors()))
+		cm.explanation = errors.New(cmp.Diff(cm.expected, actual, cmpopts.EquateErrors()))
 	}
 	return match, nil
 }
 
 func (cm *cmpMatcher) FailureMessage(actual interface{}) string {
-	return format.Message(actual, "to deeply equal", cm.expected) +
-		"\nDiff:\n" + indent(cm.explanation.Error(), 1)
+	return "\n" + format.Message(actual, "to deeply equal", cm.expected) +
+		"\nDiff (- Expected, + Actual):\n" + indent(cm.explanation.Error(), 1)
 }
 
 func (cm *cmpMatcher) NegatedFailureMessage(actual interface{}) string {
-	return format.Message(actual, "not to deeply equal", cm.expected) +
-		"\nDiff:\n" + indent(cm.explanation.Error(), 1)
+	return "\n" + format.Message(actual, "not to deeply equal", cm.expected) +
+		"\nDiff (- Expected, + Actual):\n" + indent(cm.explanation.Error(), 1)
 }
 
 func indent(in string, indentation uint) string {
@@ -111,7 +112,7 @@ func (e equalErrorString) Is(err error) bool {
 
 // AssertEqual fails the test if the actual value does not deeply equal the
 // expected value. Prints a diff on failure.
-func AssertEqual(t *testing.T, actual, expected interface{}) {
+func AssertEqual(t *testing.T, expected, actual interface{}, msgAndArgs ...interface{}) {
 	t.Helper() // print the caller's file:line, instead of this func, on failure
 	matcher := Equal(expected)
 	match, err := matcher.Match(actual)
@@ -119,13 +120,13 @@ func AssertEqual(t *testing.T, actual, expected interface{}) {
 		t.Errorf("errored testing equality: %s", err)
 	}
 	if !match {
-		t.Error(matcher.FailureMessage(actual))
+		assert.Fail(t, matcher.FailureMessage(actual), msgAndArgs...)
 	}
 }
 
 // AssertNotEqual fails the test if the actual value deeply equals the
 // expected value. Prints a diff on failure.
-func AssertNotEqual(t *testing.T, actual, expected interface{}) {
+func AssertNotEqual(t *testing.T, expected, actual interface{}, msgAndArgs ...interface{}) {
 	t.Helper() // print the caller's file:line, instead of this func, on failure
 	matcher := Equal(expected)
 	match, err := matcher.Match(actual)
@@ -133,6 +134,6 @@ func AssertNotEqual(t *testing.T, actual, expected interface{}) {
 		t.Errorf("errored testing equality: %s", err)
 	}
 	if match {
-		t.Error(matcher.NegatedFailureMessage(actual))
+		assert.Fail(t, matcher.NegatedFailureMessage(actual), msgAndArgs...)
 	}
 }