fix: Unordered arrays of objects with PRESENCE fix (#40)

Author: kinbiko

array.go

@@ -49,7 +49,7 @@ func (a *Asserter) checkArrayUnordered(path string, act, exp []interface{}) {
 	for i, expEl := range exp {
 		found := false
 		for _, actEl := range act {
-			found = found || a.deepEqual(expEl, actEl)
+			found = found || a.deepEqual(actEl, expEl)
 		}
 		if !found {
 			serializedEl := serialize(expEl)
@@ -62,16 +62,6 @@ func (a *Asserter) checkArrayUnordered(path string, act, exp []interface{}) {
 	}
 }
 
-func (a *Asserter) deepEqual(act, exp interface{}) bool {
-	// There's a non-zero chance that JSON serialization will *not* be
-	// deterministic in the future like it is in v1.16.
-	// However, until this is the case, I can't seem to find a test case that
-	// makes this evaluation return a false positive.
-	// The benefit is a lot of simplicity and considerable performance benefits
-	// for large nested structures.
-	return serialize(act) == serialize(exp)
-}
-
 func (a *Asserter) checkArrayOrdered(path string, act, exp []interface{}) {
 	a.tt.Helper()
 	if len(act) != len(exp) {

helper.go

@@ -12,3 +12,18 @@ type noopHelperTT struct {
 func (*noopHelperTT) Helper() {
 	// Intentional NOOP
 }
+
+// deepEqualityPrinter is a utility Printer that lets the jsonassert package
+// verify equality internally without affecting the external facing output,
+// e.g. to verify where one potential candidate is matching or not.
+type deepEqualityPrinter struct{ count int }
+
+func (p *deepEqualityPrinter) Errorf(msg string, args ...interface{}) { p.count++ }
+func (p *deepEqualityPrinter) Helper()                                { /* Intentional NOOP */ }
+
+func (a *Asserter) deepEqual(act, exp interface{}) bool {
+	p := &deepEqualityPrinter{count: 0}
+	deepEqualityAsserter := &Asserter{tt: p}
+	deepEqualityAsserter.pathassertf("", serialize(act), serialize(exp))
+	return p.count == 0
+}

integration_test.go

@@ -306,6 +306,12 @@ but expected JSON was:
 					`["<<UNORDERED>>", {"1": 1}, {"2": 2}, {"3": 3}, {"4": 4}, {"5": 5}, {"6": 6}, {"7": 7}, {"8": 8}, {"9": 9}, {"10": 10}, {"11": 11}, {"12": 12}, {"13": 13}, {"14": 14}, {"15": 15}, {"16": 16}, {"17": 17}, {"18": 18}, {"19": 19}, {"20": 20}]`,
 					nil,
 				},
+				"unordered array with objects with PRESENCE directives": {
+					// Regression test for https://github.com/kinbiko/jsonassert/issues/39
+					`{ "data": [ { "foo": 1, "bar": 2 }, { "foo": 11, "bar": 22 } ] }`,
+					`{ "data": [ "<<UNORDERED>>", { "foo": 11, "bar": "<<PRESENCE>>" }, { "foo": 1, "bar": "<<PRESENCE>>" } ] }`,
+					nil,
+				},
 			} {
 				tc := tc
 				t.Run(name, func(t *testing.T) { tc.check(t) })