From e3adf71edff75df68040e908b84665098954494a Mon Sep 17 00:00:00 2001
From: vyourtchenko <vyourtchenko@connamara.com>
Date: Fri, 5 Dec 2025 19:52:21 -0600
Subject: [PATCH 1/2] Fixed broken tests after fixing parsing to validate
 checksum

---
 message.go              | 45 +++++++++++++++++++++---
 message_router_test.go  | 24 +++++++++----
 message_test.go         | 14 ++++----
 repeating_group_test.go |  2 +-
 validation_test.go      | 77 +++++++++++++++++++++++------------------
 5 files changed, 111 insertions(+), 51 deletions(-)

diff --git a/message.go b/message.go
index 35e2ff675..010619b4a 100644
--- a/message.go
+++ b/message.go
@@ -182,11 +182,17 @@ func ParseMessageWithDataDictionary(
 // doParsing executes the message parsing process.
 func doParsing(mp *msgParser) (err error) {
 	mp.msg.Header.rwLock.Lock()
-	defer mp.msg.Header.rwLock.Unlock()
 	mp.msg.Body.rwLock.Lock()
-	defer mp.msg.Body.rwLock.Unlock()
 	mp.msg.Trailer.rwLock.Lock()
-	defer mp.msg.Trailer.rwLock.Unlock()
+
+	locked := true
+	defer func() {
+		if locked {
+			mp.msg.Header.rwLock.Unlock()
+			mp.msg.Body.rwLock.Unlock()
+			mp.msg.Trailer.rwLock.Unlock()
+		}
+	}()
 
 	// Initialize for parsing.
 	mp.msg.Header.clearNoLock()
@@ -294,13 +300,44 @@ func doParsing(mp *msgParser) (err error) {
 		}
 	}
 
-	bodyLength, err := mp.msg.Header.getIntNoLock(tagBodyLength)
+	var bodyLength int
+	bodyLength, err = mp.msg.Header.getIntNoLock(tagBodyLength)
 	if err != nil {
 		err = parseError{OrigError: err.Error()}
 	} else if length != bodyLength && !xmlDataMsg {
 		err = parseError{OrigError: fmt.Sprintf("Incorrect Message Length, expected %d, got %d", bodyLength, length)}
 	}
 
+	mp.msg.Header.rwLock.Unlock()
+	mp.msg.Body.rwLock.Unlock()
+	mp.msg.Trailer.rwLock.Unlock()
+	locked = false
+	if err != nil {
+		return err
+	}
+
+	calculatedCheckSum := 0
+	for i := 0; i <= mp.fieldIndex; i++ {
+		if mp.msg.fields[i].tag == tagCheckSum {
+			continue
+		}
+		calculatedCheckSum += mp.msg.fields[i].total()
+	}
+
+	calculatedCheckSum = calculatedCheckSum % 256
+
+	var expectedCheckSumStr string
+	expectedCheckSumStr, err = mp.msg.Trailer.GetString(tagCheckSum)
+	if err != nil {
+		return parseError{OrigError: "CheckSum tag missing"}
+	}
+
+	if expectedCheckSumStr != formatCheckSum(calculatedCheckSum) {
+		return parseError{
+			OrigError: fmt.Sprintf("Expected CheckSum=%s, Received CheckSum=%s", formatCheckSum(calculatedCheckSum), expectedCheckSumStr),
+		}
+	}
+
 	return
 }
 
diff --git a/message_router_test.go b/message_router_test.go
index b2e7b59f5..1b1f8f7e4 100644
--- a/message_router_test.go
+++ b/message_router_test.go
@@ -115,7 +115,7 @@ func (suite *MessageRouterTestSuite) SetupTest() {
 }
 
 func (suite *MessageRouterTestSuite) TestNoRoute() {
-	suite.givenTheMessage([]byte("8=FIX.4.3
9=87
35=D
49=TW
34=3
56=ISLD
52=20160421-14:43:50
40=1
60=20160421-14:43:50
54=1
21=3
11=id
10=235
"))
+	suite.givenTheMessage([]byte("8=FIX.4.3
9=87
35=D
49=TW
34=3
56=ISLD
52=20160421-14:43:50
40=1
60=20160421-14:43:50
54=1
21=3
11=id
10=236
"))
 
 	rej := suite.Route(suite.msg, suite.sessionID)
 	suite.verifyMessageNotRouted()
@@ -123,17 +123,29 @@ func (suite *MessageRouterTestSuite) TestNoRoute() {
 }
 
 func (suite *MessageRouterTestSuite) TestNoRouteWhitelistedMessageTypes() {
-	var tests = []string{"0", "A", "1", "2", "3", "4", "5", "j"}
+	var tests = []struct {
+		msgType  string
+		checksum string
+	}{
+		{"0", "216"},
+		{"A", "233"},
+		{"1", "217"},
+		{"2", "218"},
+		{"3", "219"},
+		{"4", "220"},
+		{"5", "221"},
+		{"j", "018"},
+	}
 
 	for _, test := range tests {
 		suite.SetupTest()
 
-		msg := fmt.Sprintf("8=FIX.4.3
9=87
35=%v
49=TW
34=3
56=ISLD
52=20160421-14:43:50
40=1
60=20160421-14:43:50
54=1
21=3
11=id
10=235
", test)
+		msg := fmt.Sprintf("8=FIX.4.3
9=87
35=%s
49=TW
34=3
56=ISLD
52=20160421-14:43:50
40=1
60=20160421-14:43:50
54=1
21=3
11=id
10=%s
", test.msgType, test.checksum)
 		suite.givenTheMessage([]byte(msg))
 
 		rej := suite.Route(suite.msg, suite.sessionID)
 		suite.verifyMessageNotRouted()
-		suite.Nil(rej, "Message type '%v' should not be rejected by the MessageRouter", test)
+		suite.Nil(rej, "Message type '%s' should not be rejected by the MessageRouter", test.msgType)
 	}
 }
 
@@ -174,7 +186,7 @@ func (suite *MessageRouterTestSuite) TestRouteFIXT50AppWithApplVerID() {
 	suite.givenTheRoute(ApplVerIDFIX50, "D")
 	suite.givenTheRoute(ApplVerIDFIX50SP1, "D")
 
-	suite.givenTheMessage([]byte("8=FIXT.1.1
9=89
35=D
49=TW
34=3
56=ISLD
52=20160424-16:48:26
1128=7
40=1
60=20160424-16:48:26
11=id
21=3
10=120
"))
+	suite.givenTheMessage([]byte("8=FIXT.1.1
9=89
35=D
49=TW
34=3
56=ISLD
52=20160424-16:48:26
1128=7
40=1
60=20160424-16:48:26
11=id
21=3
10=192
"))
 	rej := suite.Route(suite.msg, suite.sessionID)
 	suite.verifyMessageRoutedBy(ApplVerIDFIX50, "D")
 	suite.Nil(rej)
@@ -185,7 +197,7 @@ func (suite *MessageRouterTestSuite) TestRouteFIXTAppWithApplVerID() {
 	suite.givenTheRoute(ApplVerIDFIX50, "D")
 	suite.givenTheRoute(ApplVerIDFIX50SP1, "D")
 
-	suite.givenTheMessage([]byte("8=FIXT.1.1
9=89
35=D
49=TW
34=3
56=ISLD
52=20160424-16:48:26
1128=8
40=1
60=20160424-16:48:26
11=id
21=3
10=120
"))
+	suite.givenTheMessage([]byte("8=FIXT.1.1
9=89
35=D
49=TW
34=3
56=ISLD
52=20160424-16:48:26
1128=8
40=1
60=20160424-16:48:26
11=id
21=3
10=193
"))
 	rej := suite.Route(suite.msg, suite.sessionID)
 	suite.verifyMessageRoutedBy(ApplVerIDFIX50SP1, "D")
 	suite.Nil(rej)
diff --git a/message_test.go b/message_test.go
index b02508cd9..bc8a386a9 100644
--- a/message_test.go
+++ b/message_test.go
@@ -65,7 +65,7 @@ func (s *MessageSuite) TestParseMessageEmpty() {
 }
 
 func (s *MessageSuite) TestParseMessage() {
-	rawMsg := bytes.NewBufferString("8=FIX.4.2
9=104
35=D
34=2
49=TW
52=20140515-19:49:56.659
56=ISLD
11=100
21=1
40=1
54=1
55=TSLA
60=00010101-00:00:00.000
10=039
")
+	rawMsg := bytes.NewBufferString("8=FIX.4.2
9=104
35=D
34=2
49=TW
52=20140515-19:49:56.659
56=ISLD
11=100
21=1
40=1
54=1
55=TSLA
60=00010101-00:00:00.000
10=051
")
 
 	err := ParseMessage(s.msg, rawMsg)
 	s.Nil(err)
@@ -99,7 +99,7 @@ func (s *MessageSuite) TestParseMessageWithDataDictionary() {
 			5050: nil,
 		},
 	}
-	rawMsg := bytes.NewBufferString("8=FIX.4.2
9=126
35=D
34=2
49=TW
52=20140515-19:49:56.659
56=ISLD
10030=CUST
11=100
21=1
40=1
54=1
55=TSLA
60=00010101-00:00:00.000
5050=HELLO
10=039
")
+	rawMsg := bytes.NewBufferString("8=FIX.4.2
9=126
35=D
34=2
49=TW
52=20140515-19:49:56.659
56=ISLD
10030=CUST
11=100
21=1
40=1
54=1
55=TSLA
60=00010101-00:00:00.000
5050=HELLO
10=036
")
 
 	err := ParseMessageWithDataDictionary(s.msg, rawMsg, dict, dict)
 	s.Nil(err)
@@ -127,7 +127,7 @@ func (s *MessageSuite) TestBuild() {
 }
 
 func (s *MessageSuite) TestReBuild() {
-	rawMsg := bytes.NewBufferString("8=FIX.4.2
9=104
35=D
34=2
49=TW
52=20140515-19:49:56.659
56=ISLD
11=100
21=1
40=1
54=1
55=TSLA
60=00010101-00:00:00.000
10=039
")
+	rawMsg := bytes.NewBufferString("8=FIX.4.2
9=104
35=D
34=2
49=TW
52=20140515-19:49:56.659
56=ISLD
11=100
21=1
40=1
54=1
55=TSLA
60=00010101-00:00:00.000
10=051
")
 
 	s.Nil(ParseMessage(s.msg, rawMsg))
 
@@ -419,7 +419,7 @@ func (s *MessageSuite) TestReBuildWithRepeatingGroupForResend() {
 }
 
 func (s *MessageSuite) TestReverseRoute() {
-	s.Nil(ParseMessage(s.msg, bytes.NewBufferString("8=FIX.4.2
9=171
35=D
34=2
49=TW
50=KK
52=20060102-15:04:05
56=ISLD
57=AP
144=BB
115=JCD
116=CS
128=MG
129=CB
142=JV
143=RY
145=BH
11=ID
21=3
38=100
40=w
54=1
55=INTC
60=20060102-15:04:05
10=123
")))
+	s.Nil(ParseMessage(s.msg, bytes.NewBufferString("8=FIX.4.2
9=171
35=D
34=2
49=TW
50=KK
52=20060102-15:04:05
56=ISLD
57=AP
144=BB
115=JCD
116=CS
128=MG
129=CB
142=JV
143=RY
145=BH
11=ID
21=3
38=100
40=w
54=1
55=INTC
60=20060102-15:04:05
10=033
")))
 
 	builder := s.msg.reverseRoute()
 
@@ -450,7 +450,7 @@ func (s *MessageSuite) TestReverseRoute() {
 }
 
 func (s *MessageSuite) TestReverseRouteIgnoreEmpty() {
-	s.Nil(ParseMessage(s.msg, bytes.NewBufferString("8=FIX.4.0
9=128
35=D
34=2
49=TW
52=20060102-15:04:05
56=ISLD
115=
116=CS
128=MG
129=CB
11=ID
21=3
38=100
40=w
54=1
55=INTC
60=20060102-15:04:05
10=123
")))
+	s.Nil(ParseMessage(s.msg, bytes.NewBufferString("8=FIX.4.0
9=128
35=D
34=2
49=TW
52=20060102-15:04:05
56=ISLD
115=
116=CS
128=MG
129=CB
11=ID
21=3
38=100
40=w
54=1
55=INTC
60=20060102-15:04:05
10=041
")))
 	builder := s.msg.reverseRoute()
 
 	s.False(builder.Header.Has(tagDeliverToCompID), "Should not reverse if empty")
@@ -458,7 +458,7 @@ func (s *MessageSuite) TestReverseRouteIgnoreEmpty() {
 
 func (s *MessageSuite) TestReverseRouteFIX40() {
 	// The onbehalfof/deliverto location id not supported in fix 4.0.
-	s.Nil(ParseMessage(s.msg, bytes.NewBufferString("8=FIX.4.0
9=171
35=D
34=2
49=TW
50=KK
52=20060102-15:04:05
56=ISLD
57=AP
144=BB
115=JCD
116=CS
128=MG
129=CB
142=JV
143=RY
145=BH
11=ID
21=3
38=100
40=w
54=1
55=INTC
60=20060102-15:04:05
10=123
")))
+	s.Nil(ParseMessage(s.msg, bytes.NewBufferString("8=FIX.4.0
9=171
35=D
34=2
49=TW
50=KK
52=20060102-15:04:05
56=ISLD
57=AP
144=BB
115=JCD
116=CS
128=MG
129=CB
142=JV
143=RY
145=BH
11=ID
21=3
38=100
40=w
54=1
55=INTC
60=20060102-15:04:05
10=031
")))
 
 	builder := s.msg.reverseRoute()
 
@@ -468,7 +468,7 @@ func (s *MessageSuite) TestReverseRouteFIX40() {
 }
 
 func (s *MessageSuite) TestCopyIntoMessage() {
-	msgString := "8=FIX.4.2
9=171
35=D
34=2
49=TW
50=KK
52=20060102-15:04:05
56=ISLD
57=AP
144=BB
115=JCD
116=CS
128=MG
129=CB
142=JV
143=RY
145=BH
11=ID
21=3
38=100
40=w
54=1
55=INTC
60=20060102-15:04:05
10=123
"
+	msgString := "8=FIX.4.2
9=171
35=D
34=2
49=TW
50=KK
52=20060102-15:04:05
56=ISLD
57=AP
144=BB
115=JCD
116=CS
128=MG
129=CB
142=JV
143=RY
145=BH
11=ID
21=3
38=100
40=w
54=1
55=INTC
60=20060102-15:04:05
10=033
"
 	msgBuf := bytes.NewBufferString(msgString)
 	s.Nil(ParseMessage(s.msg, msgBuf))
 
diff --git a/repeating_group_test.go b/repeating_group_test.go
index abd316d78..e7d5db481 100644
--- a/repeating_group_test.go
+++ b/repeating_group_test.go
@@ -230,7 +230,7 @@ func TestRepeatingGroup_ReadRecursive(t *testing.T) {
 
 func TestRepeatingGroup_ReadComplete(t *testing.T) {
 
-	rawMsg := bytes.NewBufferString("8=FIXT.1.1
9=268
35=W
34=7118
49=TEST
52=20151027-18:41:52.698
56=TST
22=99
48=TSTX15
262=7
268=4
269=4
270=0.07499
272=20151027
273=18:41:52.698
269=7
270=0.07501
272=20151027
273=18:41:52.698
269=8
270=0.07494
272=20151027
273=18:41:52.698
269=B
271=60
272=20151027
273=18:41:52.698
10=163
")
+	rawMsg := bytes.NewBufferString("8=FIXT.1.1
9=268
35=W
34=7118
49=TEST
52=20151027-18:41:52.698
56=TST
22=99
48=TSTX15
262=7
268=4
269=4
270=0.07499
272=20151027
273=18:41:52.698
269=7
270=0.07501
272=20151027
273=18:41:52.698
269=8
270=0.07494
272=20151027
273=18:41:52.698
269=B
271=60
272=20151027
273=18:41:52.698
10=094
")
 
 	msg := NewMessage()
 	err := ParseMessage(msg, rawMsg)
diff --git a/validation_test.go b/validation_test.go
index 7973464d1..67217d4f1 100644
--- a/validation_test.go
+++ b/validation_test.go
@@ -20,8 +20,6 @@ import (
 	"testing"
 	"time"
 
-	"github.com/stretchr/testify/assert"
-
 	"github.com/quickfixgo/quickfix/datadictionary"
 )
 
@@ -32,6 +30,7 @@ type validateTest struct {
 	ExpectedRejectReason int
 	ExpectedRefTagID     *Tag
 	DoNotExpectReject    bool
+	ExpectParseError     bool
 }
 
 func TestValidate(t *testing.T) {
@@ -90,38 +89,49 @@ func TestValidate(t *testing.T) {
 
 	msg := NewMessage()
 	for _, test := range tests {
-		assert.Nil(t, ParseMessage(msg, bytes.NewBuffer(test.MessageBytes)))
-		reject := test.Validator.Validate(msg)
+		t.Run(test.TestName, func(t *testing.T) {
+			err := ParseMessage(msg, bytes.NewBuffer(test.MessageBytes))
+
+			if test.ExpectParseError {
+				if err == nil {
+					t.Errorf("%v: Expected ParseMessage to fail, but it succeeded", test.TestName)
+				}
+				return
+			}
 
-		switch {
-		case reject == nil && test.DoNotExpectReject:
-			continue
+			if err != nil {
+				t.Fatalf("ParseMessage failed: %v", err)
+			}
+			reject := test.Validator.Validate(msg)
 
-		case reject != nil && test.DoNotExpectReject:
-			t.Errorf("%v: Unexpected reject: %v", test.TestName, reject)
-			continue
+			switch {
+			case reject == nil && test.DoNotExpectReject:
+				return
 
-		case reject == nil:
-			t.Errorf("%v: Expected reject", test.TestName)
-			continue
-		}
+			case reject != nil && test.DoNotExpectReject:
+				t.Errorf("%v: Unexpected reject: %v", test.TestName, reject)
+				return
 
-		if reject.RejectReason() != test.ExpectedRejectReason {
-			t.Errorf("%v: Expected reason %v got %v", test.TestName, test.ExpectedRejectReason, reject.RejectReason())
-		}
+			case reject == nil:
+				t.Errorf("%v: Expected reject", test.TestName)
+				return
+			}
 
-		switch {
-		case reject.RefTagID() == nil && test.ExpectedRefTagID == nil:
-		// OK, expected and actual ref tag not set.
-		case reject.RefTagID() != nil && test.ExpectedRefTagID == nil:
-			t.Errorf("%v: Unexpected RefTag '%v'", test.TestName, *reject.RefTagID())
-		case reject.RefTagID() == nil && test.ExpectedRefTagID != nil:
-			t.Errorf("%v: Expected RefTag '%v'", test.TestName, *test.ExpectedRefTagID)
-		case *reject.RefTagID() == *test.ExpectedRefTagID:
-			// OK, tags equal.
-		default:
-			t.Errorf("%v: Expected RefTag '%v' got '%v'", test.TestName, *test.ExpectedRefTagID, *reject.RefTagID())
-		}
+			if reject.RejectReason() != test.ExpectedRejectReason {
+				t.Errorf("%v: Expected reason %v got %v", test.TestName, test.ExpectedRejectReason, reject.RejectReason())
+			}
+
+			switch {
+			case reject.RefTagID() == nil && test.ExpectedRefTagID == nil:
+			case reject.RefTagID() != nil && test.ExpectedRefTagID == nil:
+				t.Errorf("%v: Unexpected RefTag '%v'", test.TestName, *reject.RefTagID())
+			case reject.RefTagID() == nil && test.ExpectedRefTagID != nil:
+				t.Errorf("%v: Expected RefTag '%v'", test.TestName, *test.ExpectedRefTagID)
+			case *reject.RefTagID() == *test.ExpectedRefTagID:
+			default:
+				t.Errorf("%v: Expected RefTag '%v' got '%v'", test.TestName, *test.ExpectedRefTagID, *reject.RefTagID())
+			}
+		})
 	}
 }
 
@@ -201,6 +211,7 @@ func tcInvalidTagNumberHeader() validateTest {
 	invalidHeaderFieldMessage := createFIX40NewOrderSingle()
 	tag := Tag(9999)
 	invalidHeaderFieldMessage.Header.SetField(tag, FIXString("hello"))
+	invalidHeaderFieldMessage.cook()
 	msgBytes := invalidHeaderFieldMessage.build()
 
 	return validateTest{
@@ -1109,7 +1120,7 @@ func tcTagAppearsMoreThanOnce() validateTest {
 	return validateTest{
 		TestName:             "Tag appears more than once",
 		Validator:            validator,
-		MessageBytes:         []byte("8=FIX.4.0
9=107
35=D
34=2
49=TW
52=20060102-15:04:05
56=ISLD
11=ID
21=1
40=1
40=2
54=1
38=200
55=INTC
60=20060102-15:04:05
10=234
"),
+		MessageBytes:         []byte("8=FIX.4.0
9=107
35=D
34=2
49=TW
52=20060102-15:04:05
56=ISLD
11=ID
21=1
40=1
40=2
54=1
38=200
55=INTC
60=20060102-15:04:05
10=166
"),
 		ExpectedRejectReason: rejectReasonTagAppearsMoreThanOnce,
 		ExpectedRefTagID:     &tag,
 	}
@@ -1124,7 +1135,7 @@ func tcTagAppearsMoreThanOnceFixT() validateTest {
 	return validateTest{
 		TestName:             "Tag appears more than once FIXT",
 		Validator:            validator,
-		MessageBytes:         []byte("8=FIXT.1.1
9=107
35=D
34=2
49=TW
52=20060102-15:04:05
56=ISLD
11=ID
21=1
40=1
40=2
54=1
38=200
55=INTC
60=20060102-15:04:05
10=234
"),
+		MessageBytes:         []byte("8=FIXT.1.1
9=107
35=D
34=2
49=TW
52=20060102-15:04:05
56=ISLD
11=ID
21=1
40=1
40=2
54=1
38=200
55=INTC
60=20060102-15:04:05
10=248
"),
 		ExpectedRejectReason: rejectReasonTagAppearsMoreThanOnce,
 		ExpectedRefTagID:     &tag,
 	}
@@ -1151,7 +1162,7 @@ func tcFloatValidationFixT() validateTest {
 	return validateTest{
 		TestName:             "FloatValidation FIXT",
 		Validator:            validator,
-		MessageBytes:         []byte("8=FIXT.1.1
9=106
35=D
34=2
49=TW
52=20140329-22:38:45
56=ISLD
11=ID
21=1
40=1
54=1
38=+200.00
55=INTC
60=20140329-22:38:45
10=178
"),
+		MessageBytes:         []byte("8=FIXT.1.1
9=106
35=D
34=2
49=TW
52=20140329-22:38:45
56=ISLD
11=ID
21=1
40=1
54=1
38=+200.00
55=INTC
60=20140329-22:38:45
10=002
"),
 		ExpectedRejectReason: rejectReasonIncorrectDataFormatForValue,
 		ExpectedRefTagID:     &tag,
 	}
@@ -1163,7 +1174,7 @@ func tcMultipleRepeatingGroupFields() validateTest {
 	return validateTest{
 		TestName:          "Multiple repeating group fields in a message",
 		Validator:         validator,
-		MessageBytes:      []byte("8=FIX.4.3
9=176
35=D
34=2
49=TW
52=20140329-22:38:45
56=ISLD
11=ID
453=2
448=PARTYID
452=3
523=SUBID
448=PARTYID2
452=3
78=1
79=ACCOUNT
80=1
21=1
40=1
54=1
38=200
55=INTC
60=20140329-22:38:45
10=178
"),
+		MessageBytes:      []byte("8=FIX.4.3
9=176
35=D
34=2
49=TW
52=20140329-22:38:45
56=ISLD
11=ID
453=2
448=PARTYID
452=3
523=SUBID
448=PARTYID2
452=3
78=1
79=ACCOUNT
80=1
21=1
40=1
54=1
38=200
55=INTC
60=20140329-22:38:45
10=012
"),
 		DoNotExpectReject: true,
 	}
 }

From a693b59516a41875ae6066b56077fa163d5aa300 Mon Sep 17 00:00:00 2001
From: vyourtchenko <vyourtchenko@connamara.com>
Date: Fri, 5 Dec 2025 19:53:49 -0600
Subject: [PATCH 2/2] Added validation test for incorrect checksum

---
 validation_test.go | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/validation_test.go b/validation_test.go
index 67217d4f1..e8ec8e4e3 100644
--- a/validation_test.go
+++ b/validation_test.go
@@ -85,6 +85,7 @@ func TestValidate(t *testing.T) {
 		tcCheckUserDefinedFieldsDisabled(),
 		tcCheckUserDefinedFieldsDisabledFixT(),
 		tcMultipleRepeatingGroupFields(),
+		tcCheckSumValidation(),
 	}
 
 	msg := NewMessage()
@@ -1179,6 +1180,17 @@ func tcMultipleRepeatingGroupFields() validateTest {
 	}
 }
 
+func tcCheckSumValidation() validateTest {
+	dict, _ := datadictionary.Parse("spec/FIX43.xml")
+	validator := NewValidator(defaultValidatorSettings, dict, nil)
+	return validateTest{
+		TestName:         "Checksum is incorrect",
+		Validator:        validator,
+		MessageBytes:     []byte("8=FIX.4.3
9=176
35=D
34=2
49=TW
52=20140329-22:38:45
56=ISLD
11=ID
453=2
448=PARTYID
452=3
523=SUBID
448=PARTYID2
452=3
78=1
79=ACCOUNT
80=1
21=1
40=1
54=1
38=200
55=INTC
60=20140329-22:38:45
10=006
"),
+		ExpectParseError: true,
+	}
+}
+
 func TestValidateVisitField(t *testing.T) {
 	fieldType0 := datadictionary.NewFieldType("myfield", 11, "STRING")
 	fieldDef0 := &datadictionary.FieldDef{FieldType: fieldType0}