remove codecov badge

add error handling to arg encoding and message/bundle ToBytes()

.gitignore

@@ -1 +1,2 @@
-build
+build
+coverage*

README.md

@@ -1,5 +1,7 @@
-A collection of command line OSC utilities written in Go. Mainly an exercise in learning Go.
+A mostly complete OSC implementation and collection of command line OSC utilities written in Go. Mainly an exercise in learning Go.
 
-# `sendosc`
-# `makeosc`
-# `receiveosc`
+## Utilities
+
+### `sendosc`
+### `makeosc`
+### `receiveosc`

bundle.go

@@ -4,30 +4,41 @@ import (
 	"errors"
 )
 
-func (b *OSCBundle) ToBytes() []byte {
+func (b *OSCBundle) ToBytes() ([]byte, error) {
 
 	bytes := stringToOSCBytes("#bundle")
 
-	bytes = append(bytes, timeTagToOSCBytes(b.TimeTag)...)
+	timeTagBytes, err := timeTagToOSCBytes(b.TimeTag)
+	if err != nil {
+		return nil, err
+	}
+	bytes = append(bytes, timeTagBytes...)
 
 	for _, packet := range b.Contents {
-		packetBytes := packet.ToBytes()
-		packetLength := len(packet.ToBytes())
+		packetBytes, err := packet.ToBytes()
+		if err != nil {
+			return nil, err
+		}
+		packetLength := len(packetBytes)
 
-		bytes = append(bytes, int32ToOSCBytes(int32(packetLength))...)
+		packetLengthBytes, err := int32ToOSCBytes(int32(packetLength))
+		if err != nil {
+			return nil, err
+		}
+		bytes = append(bytes, packetLengthBytes...)
 		bytes = append(bytes, packetBytes...)
 	}
 
-	return bytes
+	return bytes, nil
 }
 
 func BundleFromBytes(bytes []byte) (*OSCBundle, []byte, error) {
 	if len(bytes) < 20 {
-		return nil, bytes, errors.New("bundle has to be at least 20 bytes")
+		return nil, bytes, errors.New("OSC Bundle has to be at least 20 bytes")
 	}
 
 	if bytes[0] != 35 {
-		return nil, bytes, errors.New("bundle must start with a #")
+		return nil, bytes, errors.New("OSC Bundle must start with a #")
 	}
 
 	bundleHeader, bytesAfterBundleHeader, err := readOSCString(bytes)
@@ -37,7 +48,7 @@ func BundleFromBytes(bytes []byte) (*OSCBundle, []byte, error) {
 	}
 
 	if bundleHeader != "#bundle" {
-		return nil, bytesAfterBundleHeader, errors.New("bundle must start with #bundle string")
+		return nil, bytesAfterBundleHeader, errors.New("OSC Bundle must start with #bundle string")
 	}
 
 	timeTag, bytesAfterTimeTag, err := readOSCTimeTag(bytesAfterBundleHeader)

bundle_test.go

@@ -1,89 +1,212 @@
 package osc
 
 import (
-	"fmt"
 	"reflect"
 	"testing"
 )
 
-func TestOSCBundleEncoding(t *testing.T) {
+func TestGoodOSCBundleEncoding(t *testing.T) {
 
 	testCases := []struct {
-		description string
+		name     string
+		bundle   *OSCBundle
+		expected []byte
+	}{
+		{
+			name: "simple contents single message",
+			bundle: &OSCBundle{
+				TimeTag: OSCTimeTag{
+					seconds:           32,
+					fractionalSeconds: 0,
+				},
+				Contents: []OSCPacket{&OSCMessage{Address: "/oscillator/4/frequency", Args: []OSCArg{{Type: "f", Value: float32(440)}}}},
+			},
+			expected: []byte{35, 98, 117, 110, 100, 108, 101, 0, 0, 0, 0,
+				32, 0, 0, 0, 0, 0, 0, 0, 32, 47, 111,
+				115, 99, 105, 108, 108, 97, 116, 111, 114, 47, 52,
+				47, 102, 114, 101, 113, 117, 101, 110, 99, 121, 0,
+				44, 102, 0, 0, 67, 220, 0, 0},
+		},
+	}
+
+	for _, testCase := range testCases {
+		t.Run(testCase.name, func(t *testing.T) {
+
+			got, err := testCase.bundle.ToBytes()
+
+			if err != nil {
+				t.Fatalf("failed to encode properly: %s", err.Error())
+			}
+
+			if !reflect.DeepEqual(got, testCase.expected) {
+				t.Fatalf("failed to encode properly got '%v', expected '%v'", got, testCase.expected)
+			}
+		})
+	}
+}
+
+func TestBadOSCBundleEncoding(t *testing.T) {
+
+	testCases := []struct {
+		name        string
 		bundle      *OSCBundle
-		expected    []byte
+		errorString string
 	}{
 		{
-			"simple contents single message",
-			&OSCBundle{
+			name: "bundle contains message with bad address",
+			bundle: &OSCBundle{
 				TimeTag: OSCTimeTag{
 					seconds:           32,
 					fractionalSeconds: 0,
 				},
-				Contents: []OSCPacket{&OSCMessage{Address: "/oscillator/4/frequency", Args: []OSCArg{{Type: "f", Value: float32(440)}}}},
+				Contents: []OSCPacket{&OSCMessage{Address: "hello", Args: []OSCArg{}}},
 			},
-			[]byte{35, 98, 117, 110, 100, 108, 101, 0, 0, 0, 0,
-				32, 0, 0, 0, 0, 0, 0, 0, 32, 47, 111,
-				115, 99, 105, 108, 108, 97, 116, 111, 114, 47, 52,
-				47, 102, 114, 101, 113, 117, 101, 110, 99, 121, 0,
-				44, 102, 0, 0, 67, 220, 0, 0},
+			errorString: "OSC Message address must start with /",
 		},
 	}
 
 	for _, testCase := range testCases {
+		t.Run(testCase.name, func(t *testing.T) {
 
-		actual := testCase.bundle.ToBytes()
+			got, err := testCase.bundle.ToBytes()
 
-		if !reflect.DeepEqual(actual, testCase.expected) {
-			t.Errorf("Test '%s' failed to encode properly", testCase.description)
-			fmt.Printf("expected: %v\n", testCase.expected)
-			fmt.Printf("actual: %v\n", actual)
-		}
+			if err == nil {
+				t.Fatalf("OSCBundle.ToBytes() expected to fail but got: %+v", got)
+			}
+
+			if err.Error() != testCase.errorString {
+				t.Fatalf("OSCBundle.ToBytes() got error '%s', expected '%s'", err.Error(), testCase.errorString)
+			}
+		})
 	}
-
 }
 
-func TestOSCBundleDecoding(t *testing.T) {
+func TestGoodOSCBundleDecoding(t *testing.T) {
 	testCases := []struct {
-		description string
-		expected    *OSCBundle
-		bytes       []byte
+		name     string
+		expected *OSCBundle
+		bytes    []byte
 	}{
 		{
-			"simple contents single message",
-			&OSCBundle{
+			name: "simple contents single message",
+			expected: &OSCBundle{
 				TimeTag: OSCTimeTag{
 					seconds:           32,
 					fractionalSeconds: 0,
 				},
 				Contents: []OSCPacket{&OSCMessage{Address: "/oscillator/4/frequency", Args: []OSCArg{{Type: "f", Value: float32(440)}}}},
 			},
-			[]byte{35, 98, 117, 110, 100, 108, 101, 0, 0, 0, 0,
+			bytes: []byte{35, 98, 117, 110, 100, 108, 101, 0, 0, 0, 0,
 				32, 0, 0, 0, 0, 0, 0, 0, 32, 47, 111,
 				115, 99, 105, 108, 108, 97, 116, 111, 114, 47, 52,
 				47, 102, 114, 101, 113, 117, 101, 110, 99, 121, 0,
 				44, 102, 0, 0, 67, 220, 0, 0},
 		},
+		{
+			name: "simple contents nested bundle",
+			expected: &OSCBundle{
+				TimeTag: OSCTimeTag{
+					seconds:           32,
+					fractionalSeconds: 0,
+				},
+				Contents: []OSCPacket{&OSCBundle{
+					TimeTag: OSCTimeTag{
+						seconds:           64,
+						fractionalSeconds: 0,
+					},
+					Contents: []OSCPacket{&OSCMessage{Address: "/oscillator/4/frequency", Args: []OSCArg{{Type: "f", Value: float32(440)}}}},
+				}},
+			},
+			bytes: []byte{35, 98, 117, 110, 100, 108, 101, 0, // #bundle
+				0, 0, 0, 32, 0, 0, 0, 0, // time tag
+				0, 0, 0, 52, // content size
+				35, 98, 117, 110, 100, 108, 101, 0, // #bundle
+				0, 0, 0, 64, 0, 0, 0, 0, // time tag
+				0, 0, 0, 32, // content size
+				47, 111, 115, 99, 105, 108, 108, 97, 116, 111, 114, 47, 52,
+				47, 102, 114, 101, 113, 117, 101, 110, 99, 121, 0,
+				44, 102, 0, 0, 67, 220, 0, 0},
+		},
 	}
 
 	for _, testCase := range testCases {
+		t.Run(testCase.name, func(t *testing.T) {
+			actual, remainingBytes, error := BundleFromBytes(testCase.bytes)
 
-		actual, remainingBytes, error := BundleFromBytes(testCase.bytes)
+			if error != nil {
+				t.Fatalf("failed to decode properly: %s", error.Error())
+			}
 
-		if error != nil {
-			fmt.Println(error)
-			t.Errorf("Test '%s' failed to encode properly", testCase.description)
-		}
-
-		if len(remainingBytes) > 0 {
-			t.Errorf("Test '%s' should not have any remaining bytes", testCase.description)
-		}
-
-		if !reflect.DeepEqual(actual, testCase.expected) {
-			t.Errorf("Test '%s' failed to encode bundle properly", testCase.description)
-			fmt.Printf("expected: %v\n", testCase.expected)
-			fmt.Printf("actual: %v\n", actual)
-		}
+			if len(remainingBytes) > 0 {
+				t.Fatalf("should not have any remaining bytes")
+			}
 
+			if !reflect.DeepEqual(actual, testCase.expected) {
+				t.Fatalf("failed to decode properly got '%v', expected '%v'", actual, testCase.expected)
+			}
+		})
+	}
+}
+
+func TestBadOSCBundleDecoding(t *testing.T) {
+	testCases := []struct {
+		name        string
+		bytes       []byte
+		errorString string
+	}{
+		{
+			name:        "empty byte array",
+			bytes:       []byte{},
+			errorString: "OSC Bundle has to be at least 20 bytes",
+		},
+		{
+			name:        "does not start with #",
+			bytes:       []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+			errorString: "OSC Bundle must start with a #",
+		},
+		{
+			name:        "does not start with #bundle",
+			bytes:       []byte{35, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+			errorString: "OSC Bundle must start with #bundle string",
+		},
+		{
+			name: "bundle header not properly null terminated",
+			bytes: []byte{
+				35, 98, 117, 110, 100, 108, 101,
+				35, 35, 35, 35, 35, 35, 35, 35, 35, 35, 35, 35, 35},
+			errorString: "OSC string must be null-terminated",
+		},
+		{
+			name: "bundle contains incorrect size",
+			bytes: []byte{
+				35, 98, 117, 110, 100, 108, 101, 0, // #bundle
+				0, 0, 0, 0, 0, 0, 0, 0, // time tag
+				0, 0, 0, 100, // content size of 100 but only 10 bytes of content
+				35, 35, 35, 35, 35, 35, 35, 35, 35, 35},
+			errorString: "bundle doesn't have enough bytes for the content size it specifies",
+		},
+		{
+			name: "bundle doesn't contain message or bundle",
+			bytes: []byte{
+				35, 98, 117, 110, 100, 108, 101, 0, // #bundle
+				0, 0, 0, 0, 0, 0, 0, 0, // time tag
+				0, 0, 0, 10,
+				0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+			errorString: "bundle contents does not look a bundle or message",
+		},
+	}
+
+	for _, testCase := range testCases {
+		t.Run(testCase.name, func(t *testing.T) {
+			got, _, err := BundleFromBytes(testCase.bytes)
+
+			if err == nil {
+				t.Fatalf("BundleFromBytes expected to fail but got: %+v", got)
+			}
+
+			if err.Error() != testCase.errorString {
+				t.Fatalf("BundleFromBytes got error '%s', expected '%s'", err.Error(), testCase.errorString)
+			}
+		})
 	}
 }

cmd/makeosc/makeosc.go

@@ -175,7 +175,10 @@ func make(address string, args []string, types []string, slip bool) {
 		oscMessage.Args = append(oscMessage.Args, argToTypedArg(arg, oscType))
 	}
 
-	oscMessageBuffer := oscMessage.ToBytes()
+	oscMessageBuffer, err := oscMessage.ToBytes()
+	if err != nil {
+		panic(err)
+	}
 
 	if slip {
 		oscMessageBuffer = slipEncode(oscMessageBuffer)

cmd/sendosc/sendosc.go

@@ -208,7 +208,10 @@ func send(host string, port int32, address string, args []string, types []string
 
 	}
 
-	oscMessageBuffer := oscMessage.ToBytes()
+	oscMessageBuffer, err := oscMessage.ToBytes()
+	if err != nil {
+		panic(err)
+	}
 
 	if slip {
 		oscMessageBuffer = slipEncode(oscMessageBuffer)

message.go

@@ -5,8 +5,16 @@ import (
 	"strings"
 )
 
-func (m *OSCMessage) ToBytes() []byte {
-	//TODO(jwetzell): add error handling
+func (m *OSCMessage) ToBytes() ([]byte, error) {
+
+	if len(m.Address) == 0 {
+		return nil, errors.New("OSC Message must have an address")
+	}
+
+	if m.Address[0] != '/' {
+		return nil, errors.New("OSC Message address must start with /")
+	}
+
 	oscBuffer := []byte{}
 
 	oscBuffer = append(oscBuffer, stringToOSCBytes(m.Address)...)
@@ -18,11 +26,14 @@ func (m *OSCMessage) ToBytes() []byte {
 	for _, arg := range m.Args {
 		sb.WriteString(arg.Type)
 	}
-
 	oscBuffer = append(oscBuffer, stringToOSCBytes(sb.String())...)
-	oscBuffer = append(oscBuffer, argsToBuffer(m.Args)...)
+	argsBuffer, err := argsToBuffer(m.Args)
+	if err != nil {
+		return nil, err
+	}
+	oscBuffer = append(oscBuffer, argsBuffer...)
 
-	return oscBuffer
+	return oscBuffer, nil
 }
 
 func MessageFromBytes(bytes []byte) (*OSCMessage, error) {

message_test.go

@@ -128,16 +128,117 @@ func TestGoodOSCMessageEncoding(t *testing.T) {
 
 	for _, testCase := range testCases {
 		t.Run(testCase.name, func(t *testing.T) {
-			actual := testCase.message.ToBytes()
+			got, err := testCase.message.ToBytes()
 
-			if !reflect.DeepEqual(actual, testCase.expected) {
-				t.Fatalf("failed to encode properly got '%v', expected '%v'", actual, testCase.expected)
+			if err != nil {
+				t.Fatalf("failed to encode properly: %s", err.Error())
+			}
+
+			if !reflect.DeepEqual(got, testCase.expected) {
+				t.Fatalf("failed to encode properly got '%v', expected '%v'", got, testCase.expected)
 			}
 		})
 	}
 
 }
 
+func TestBadOSCMessageEncoding(t *testing.T) {
+	testCases := []struct {
+		name        string
+		message     *OSCMessage
+		errorString string
+	}{
+		{
+			name:        "empty message",
+			message:     &OSCMessage{},
+			errorString: "OSC Message must have an address",
+		},
+		{
+			name:        "address does not start with /",
+			message:     &OSCMessage{Address: "hello"},
+			errorString: "OSC Message address must start with /",
+		},
+		{
+			name: "arg with unsupported type",
+			message: &OSCMessage{
+				Address: "/hello",
+				Args:    []OSCArg{{Type: "x", Value: "unsupported"}},
+			},
+			errorString: "unsupported OSC argument type: x",
+		},
+		{
+			name: "string arg that is not a string",
+			message: &OSCMessage{
+				Address: "/hello",
+				Args:    []OSCArg{{Type: "s", Value: 123}},
+			},
+			errorString: "OSC arg had string type but non-string value",
+		},
+		{
+			name: "int32 arg that is not a number",
+			message: &OSCMessage{
+				Address: "/hello",
+				Args:    []OSCArg{{Type: "i", Value: "not an int"}},
+			},
+			errorString: "OSC arg had int32 type but non-number value",
+		},
+		{
+			name: "float32 arg that is not a number",
+			message: &OSCMessage{
+				Address: "/hello",
+				Args:    []OSCArg{{Type: "f", Value: "not a float"}},
+			},
+			errorString: "OSC arg had float32 type but non-number value",
+		},
+		{
+			name: "int64 arg that is not a number",
+			message: &OSCMessage{
+				Address: "/hello",
+				Args:    []OSCArg{{Type: "h", Value: "not an int"}},
+			},
+			errorString: "OSC arg had int64 type but non-number value",
+		},
+		{
+			name: "float64 arg that is not a number",
+			message: &OSCMessage{
+				Address: "/hello",
+				Args:    []OSCArg{{Type: "d", Value: "not a float"}},
+			},
+			errorString: "OSC arg had float64 type but non-number value",
+		},
+		{
+			name: "blob arg that is not a byte array",
+			message: &OSCMessage{
+				Address: "/hello",
+				Args:    []OSCArg{{Type: "b", Value: "not a blob"}},
+			},
+			errorString: "OSC arg had blob type but non-blob value",
+		},
+		{
+			name: "color arg that is not an OSCColor",
+			message: &OSCMessage{
+				Address: "/hello",
+				Args:    []OSCArg{{Type: "r", Value: "not a color"}},
+			},
+			errorString: "OSC arg had color type but non-color value",
+		},
+	}
+
+	for _, testCase := range testCases {
+		t.Run(testCase.name, func(t *testing.T) {
+			got, err := testCase.message.ToBytes()
+
+			if err == nil {
+				t.Fatalf("OSCMessage.ToBytes() expected to fail but got: %+v", got)
+			}
+
+			if err.Error() != testCase.errorString {
+				t.Fatalf("OSCMessage.ToBytes() got error '%s', expected '%s'", err.Error(), testCase.errorString)
+			}
+		})
+	}
+}
+
 func TestGoodOSCMessageDecoding(t *testing.T) {
 	testCases := []struct {
 		name     string
@@ -324,6 +425,76 @@ func TestBadOSCMessageDecoding(t *testing.T) {
 			},
 			errorString: "OSC string is not properly padded",
 		},
+		{
+			name: "int32 arg not 4 bytes",
+			bytes: []byte{
+				47, 104, 101, 108, 108, 111, 0, 0, 44, 105, 0, 0, 0,
+			},
+			errorString: "OSC int32 arg is not 4 bytes",
+		},
+		{
+			name: "int64 arg not 8 bytes",
+			bytes: []byte{
+				47, 104, 101, 108, 108, 111, 0, 0, 44, 104, 0, 0, 0, 0, 0, 0,
+			},
+			errorString: "OSC int64 arg is not 8 bytes",
+		},
+		{
+			name: "float32 arg not 4 bytes",
+			bytes: []byte{
+				47, 104, 101, 108, 108, 111, 0, 0, 44, 102, 0, 0, 66,
+			},
+			errorString: "OSC float32 arg is not 4 bytes",
+		},
+		{
+			name: "float64 arg not 8 bytes",
+			bytes: []byte{
+				47, 104, 101, 108, 108, 111, 0, 0, 44, 100, 0, 0, 0,
+			},
+			errorString: "OSC float64 arg is not 8 bytes",
+		},
+		{
+			name: "blob arg size not valid",
+			bytes: []byte{
+				47, 104, 101, 108, 108, 111, 0, 0, 44, 98, 0, 0, 0, 0, 0,
+			},
+			errorString: "OSC blob arg size not valid: OSC int32 arg is not 4 bytes",
+		},
+		{
+			name: "blob arg size mismatch",
+			bytes: []byte{
+				47, 104, 101, 108, 108, 111, 0, 0, 44, 98, 0, 0, 0, 0, 0, 4, 98, 108, 111,
+			},
+			errorString: "OSC blob arg size not valid: size specified is larger than remaining bytes",
+		},
+		{
+			name: "color arg not 4 bytes",
+			bytes: []byte{
+				47, 104, 101, 108, 108, 111, 0, 0, 44, 114, 0, 0, 20, 21,
+			},
+			errorString: "OSC color arg is not 4 bytes",
+		},
+		{
+			name: "time tag arg seconds not complete",
+			bytes: []byte{
+				47, 104, 101, 108, 108, 111, 0, 0, 44, 116, 0, 0, 0,
+			},
+			errorString: "OSC time tag seconds are not valid: OSC int32 arg is not 4 bytes",
+		},
+		{
+			name: "time tag arg fractional seconds not complete",
+			bytes: []byte{
+				47, 104, 101, 108, 108, 111, 0, 0, 44, 116, 0, 0, 0, 32, 0, 0, 0,
+			},
+			errorString: "OSC time tag fractional seconds are not valid: OSC int32 arg is not 4 bytes",
+		},
+		{
+			name: "unknown arg type",
+			bytes: []byte{
+				47, 104, 101, 108, 108, 111, 0, 0, 44, 120, 0, 0,
+			},
+			errorString: "unsupported OSC argument type: x",
+		},
 	}
 
 	for _, testCase := range testCases {

osc.go

@@ -26,47 +26,51 @@ func stringToOSCBytes(rawString string) []byte {
 	return []byte(sb.String())
 }
 
-func int32ToOSCBytes(number int32) []byte {
+func int32ToOSCBytes(number int32) ([]byte, error) {
 	var buf bytes.Buffer
 	err := binary.Write(&buf, binary.BigEndian, number)
 	if err != nil {
-		panic(err)
+		return nil, err
 	}
-	return buf.Bytes()
+	return buf.Bytes(), nil
 }
 
-func int64ToOSCBytes(number int64) []byte {
+func int64ToOSCBytes(number int64) ([]byte, error) {
 	var buf bytes.Buffer
 	err := binary.Write(&buf, binary.BigEndian, number)
 	if err != nil {
-		panic(err)
+		return nil, err
 	}
-	return buf.Bytes()
+	return buf.Bytes(), nil
 }
 
-func float32ToOSCBytes(number float32) []byte {
+func float32ToOSCBytes(number float32) ([]byte, error) {
 	var buf bytes.Buffer
 	err := binary.Write(&buf, binary.BigEndian, number)
 	if err != nil {
-		panic(err)
+		return nil, err
 	}
-	return buf.Bytes()
+	return buf.Bytes(), nil
 }
 
-func float64ToOSCBytes(number float64) []byte {
+func float64ToOSCBytes(number float64) ([]byte, error) {
 	var buf bytes.Buffer
 	err := binary.Write(&buf, binary.BigEndian, number)
 	if err != nil {
-		panic(err)
+		return nil, err
 	}
-	return buf.Bytes()
+	return buf.Bytes(), nil
 }
 
-func byteArrayToOSCBytes(bytes []byte) []byte {
+func byteArrayToOSCBytes(bytes []byte) ([]byte, error) {
 	oscBytes := []byte{}
 
 	bytesSize := len(bytes)
-	oscBytes = append(oscBytes, int32ToOSCBytes(int32(bytesSize))...)
+	bytesSizeBytes, err := int32ToOSCBytes(int32(bytesSize))
+	if err != nil {
+		return nil, err
+	}
+	oscBytes = append(oscBytes, bytesSizeBytes...)
 	oscBytes = append(oscBytes, bytes...)
 
 	padLength := 4 - (bytesSize % 4)
@@ -76,17 +80,24 @@ func byteArrayToOSCBytes(bytes []byte) []byte {
 		}
 	}
 
-	return oscBytes
+	return oscBytes, nil
 }
 
-func timeTagToOSCBytes(timeTag OSCTimeTag) []byte {
-	timeTagBytes := int32ToOSCBytes(timeTag.seconds)
-	timeTagBytes = append(timeTagBytes, int32ToOSCBytes(timeTag.fractionalSeconds)...)
+func timeTagToOSCBytes(timeTag OSCTimeTag) ([]byte, error) {
+	timeTagBytes, err := int32ToOSCBytes(timeTag.seconds)
+	if err != nil {
+		return nil, err
+	}
+	fractionalSecondsBytes, err := int32ToOSCBytes(timeTag.fractionalSeconds)
+	if err != nil {
+		return nil, err
+	}
+	timeTagBytes = append(timeTagBytes, fractionalSecondsBytes...)
 
-	return timeTagBytes
+	return timeTagBytes, nil
 }
 
-func argsToBuffer(args []OSCArg) []byte {
+func argsToBuffer(args []OSCArg) ([]byte, error) {
 	//TODO(jwetzell): add error handling
 	var argBuffers = []byte{}
 
@@ -96,35 +107,67 @@ func argsToBuffer(args []OSCArg) []byte {
 			if value, ok := arg.Value.(string); ok {
 				argBuffers = append(argBuffers, stringToOSCBytes(value)...)
 			} else {
-				fmt.Println("OSC arg had string type but non-string value.")
+				return nil, errors.New("OSC arg had string type but non-string value")
 			}
 		case "i":
 			if value, ok := arg.Value.(int); ok {
-				argBuffers = append(argBuffers, int32ToOSCBytes(int32(value))...)
+				valueBytes, err := int32ToOSCBytes(int32(value))
+				if err != nil {
+					return nil, err
+				}
+				argBuffers = append(argBuffers, valueBytes...)
 			} else if value, ok := arg.Value.(int32); ok {
-				argBuffers = append(argBuffers, int32ToOSCBytes(value)...)
+				valueBytes, err := int32ToOSCBytes(int32(value))
+				if err != nil {
+					return nil, err
+				}
+				argBuffers = append(argBuffers, valueBytes...)
 			} else {
-				fmt.Println("OSC arg had integer type but non-integer value.")
+				return nil, errors.New("OSC arg had int32 type but non-number value")
 			}
 		case "f":
 			if value, ok := arg.Value.(float32); ok {
-				argBuffers = append(argBuffers, float32ToOSCBytes(float32(value))...)
+				valueBytes, err := float32ToOSCBytes(value)
+				if err != nil {
+					return nil, err
+				}
+				argBuffers = append(argBuffers, valueBytes...)
 			} else if value, ok := arg.Value.(float64); ok {
-				argBuffers = append(argBuffers, float32ToOSCBytes(float32(value))...)
+				valueBytes, err := float32ToOSCBytes(float32(value))
+				if err != nil {
+					return nil, err
+				}
+				argBuffers = append(argBuffers, valueBytes...)
 			} else if value, ok := arg.Value.(int); ok {
-				argBuffers = append(argBuffers, float32ToOSCBytes(float32(value))...)
+				valueBytes, err := float32ToOSCBytes(float32(value))
+				if err != nil {
+					return nil, err
+				}
+				argBuffers = append(argBuffers, valueBytes...)
 			} else if value, ok := arg.Value.(int32); ok {
-				argBuffers = append(argBuffers, float32ToOSCBytes(float32(value))...)
+				valueBytes, err := float32ToOSCBytes(float32(value))
+				if err != nil {
+					return nil, err
+				}
+				argBuffers = append(argBuffers, valueBytes...)
 			} else if value, ok := arg.Value.(int64); ok {
-				argBuffers = append(argBuffers, float32ToOSCBytes(float32(value))...)
+				valueBytes, err := float32ToOSCBytes(float32(value))
+				if err != nil {
+					return nil, err
+				}
+				argBuffers = append(argBuffers, valueBytes...)
 			} else {
-				fmt.Println("OSC arg had float type but non-float value.")
+				return nil, errors.New("OSC arg had float32 type but non-number value")
 			}
 		case "b":
 			if value, ok := arg.Value.([]byte); ok {
-				argBuffers = append(argBuffers, byteArrayToOSCBytes(value)...)
+				valueBytes, err := byteArrayToOSCBytes(value)
+				if err != nil {
+					return nil, err
+				}
+				argBuffers = append(argBuffers, valueBytes...)
 			} else {
-				fmt.Println("OSC arg had blob type but non-blob value.")
+				return nil, errors.New("OSC arg had blob type but non-blob value")
 			}
 		case "T":
 			argBuffers = append(argBuffers, make([]byte, 0)...)
@@ -136,39 +179,74 @@ func argsToBuffer(args []OSCArg) []byte {
 			argBuffers = append(argBuffers, make([]byte, 0)...)
 		case "r":
 			color, ok := arg.Value.(OSCColor)
+			if !ok {
+				return nil, errors.New("OSC arg had color type but non-color value")
+			}
 			if ok {
 				colorBytes := []byte{color.r, color.g, color.b, color.a}
 				argBuffers = append(argBuffers, colorBytes...)
 			}
 		case "h":
 			if value, ok := arg.Value.(int); ok {
-				argBuffers = append(argBuffers, int64ToOSCBytes(int64(value))...)
+				valueBytes, err := int64ToOSCBytes(int64(value))
+				if err != nil {
+					return nil, err
+				}
+				argBuffers = append(argBuffers, valueBytes...)
 			} else if value, ok := arg.Value.(int32); ok {
-				argBuffers = append(argBuffers, int64ToOSCBytes(int64(value))...)
+				valueBytes, err := int64ToOSCBytes(int64(value))
+				if err != nil {
+					return nil, err
+				}
+				argBuffers = append(argBuffers, valueBytes...)
 			} else if value, ok := arg.Value.(int64); ok {
-				argBuffers = append(argBuffers, int64ToOSCBytes(value)...)
+				valueBytes, err := int64ToOSCBytes(value)
+				if err != nil {
+					return nil, err
+				}
+				argBuffers = append(argBuffers, valueBytes...)
 			} else {
-				fmt.Println("OSC arg had integer type but non-integer value.")
+				return nil, errors.New("OSC arg had int64 type but non-number value")
 			}
 		case "d":
 			if value, ok := arg.Value.(float32); ok {
-				argBuffers = append(argBuffers, float64ToOSCBytes(float64(value))...)
+				valueBytes, err := float64ToOSCBytes(float64(value))
+				if err != nil {
+					return nil, err
+				}
+				argBuffers = append(argBuffers, valueBytes...)
 			} else if value, ok := arg.Value.(float64); ok {
-				argBuffers = append(argBuffers, float64ToOSCBytes(float64(value))...)
+				valueBytes, err := float64ToOSCBytes(value)
+				if err != nil {
+					return nil, err
+				}
+				argBuffers = append(argBuffers, valueBytes...)
 			} else if value, ok := arg.Value.(int); ok {
-				argBuffers = append(argBuffers, float64ToOSCBytes(float64(value))...)
+				valueBytes, err := float64ToOSCBytes(float64(value))
+				if err != nil {
+					return nil, err
+				}
+				argBuffers = append(argBuffers, valueBytes...)
 			} else if value, ok := arg.Value.(int32); ok {
-				argBuffers = append(argBuffers, float64ToOSCBytes(float64(value))...)
+				valueBytes, err := float64ToOSCBytes(float64(value))
+				if err != nil {
+					return nil, err
+				}
+				argBuffers = append(argBuffers, valueBytes...)
 			} else if value, ok := arg.Value.(int64); ok {
-				argBuffers = append(argBuffers, float64ToOSCBytes(float64(value))...)
+				valueBytes, err := float64ToOSCBytes(float64(value))
+				if err != nil {
+					return nil, err
+				}
+				argBuffers = append(argBuffers, valueBytes...)
 			} else {
-				fmt.Println("OSC arg had float type but non-float value.")
+				return nil, errors.New("OSC arg had float64 type but non-number value")
 			}
 		default:
-			fmt.Printf("unhandled osc type: %s.\n", oscType)
+			return nil, fmt.Errorf("unsupported OSC argument type: %s", oscType)
 		}
 	}
-	return argBuffers
+	return argBuffers, nil
 }
 
 func readOSCString(bytes []byte) (string, []byte, error) {
@@ -206,7 +284,7 @@ func readOSCString(bytes []byte) (string, []byte, error) {
 
 func readOSCInt32(bytes []byte) (int32, []byte, error) {
 	if len(bytes) < 4 {
-		return 0, bytes, errors.New("int data must be at least 4 bytes large")
+		return 0, bytes, errors.New("OSC int32 arg is not 4 bytes")
 	}
 	bits := binary.BigEndian.Uint32(bytes[0:4])
 	return int32(bits), bytes[4:], nil
@@ -214,7 +292,7 @@ func readOSCInt32(bytes []byte) (int32, []byte, error) {
 
 func readOSCInt64(bytes []byte) (int64, []byte, error) {
 	if len(bytes) < 8 {
-		return 0, bytes, errors.New("int data must be at least 4 bytes large")
+		return 0, bytes, errors.New("OSC int64 arg is not 8 bytes")
 	}
 	bits := binary.BigEndian.Uint64(bytes[0:8])
 	return int64(bits), bytes[8:], nil
@@ -222,7 +300,7 @@ func readOSCInt64(bytes []byte) (int64, []byte, error) {
 
 func readOSCFloat32(bytes []byte) (float32, []byte, error) {
 	if len(bytes) < 4 {
-		return 0, bytes, errors.New("float data must be at least 4 bytes large")
+		return 0, bytes, errors.New("OSC float32 arg is not 4 bytes")
 	}
 	bits := binary.BigEndian.Uint32(bytes[0:4])
 	return math.Float32frombits(bits), bytes[4:], nil
@@ -230,7 +308,7 @@ func readOSCFloat32(bytes []byte) (float32, []byte, error) {
 
 func readOSCFloat64(bytes []byte) (float64, []byte, error) {
 	if len(bytes) < 4 {
-		return 0, bytes, errors.New("float data must be at least 4 bytes large")
+		return 0, bytes, errors.New("OSC float64 arg is not 8 bytes")
 	}
 	bits := binary.BigEndian.Uint64(bytes[0:8])
 	return math.Float64frombits(bits), bytes[8:], nil
@@ -240,11 +318,11 @@ func readOSCBlob(bytes []byte) ([]byte, []byte, error) {
 	blobLength, remainingBytes, err := readOSCInt32(bytes)
 
 	if err != nil {
-		return []byte{}, bytes, errors.New("problem reading blob data size")
+		return []byte{}, bytes, errors.New("OSC blob arg size not valid: " + err.Error())
 	}
 
 	if len(remainingBytes) < int(blobLength) {
-		return []byte{}, bytes, errors.New("blob data specified a size larger than the remaining message data")
+		return []byte{}, bytes, errors.New("OSC blob arg size not valid: size specified is larger than remaining bytes")
 	}
 
 	blobLengthPadding := 4 - (blobLength % 4)
@@ -258,7 +336,7 @@ func readOSCBlob(bytes []byte) ([]byte, []byte, error) {
 
 func readOSCColor(bytes []byte) (OSCColor, []byte, error) {
 	if len(bytes) < 4 {
-		return OSCColor{0, 0, 0, 0}, bytes, errors.New("color data must be at least 4 bytes large")
+		return OSCColor{0, 0, 0, 0}, bytes, errors.New("OSC color arg is not 4 bytes")
 	}
 	oscColor := OSCColor{
 		r: bytes[0],
@@ -268,14 +346,15 @@ func readOSCColor(bytes []byte) (OSCColor, []byte, error) {
 	}
 	return oscColor, bytes[4:], nil
 }
+
 func readOSCTimeTag(bytes []byte) (OSCTimeTag, []byte, error) {
 	seconds, bytesAfterSeconds, err := readOSCInt32(bytes)
 	if err != nil {
-		return OSCTimeTag{}, bytes, err
+		return OSCTimeTag{}, bytes, fmt.Errorf("OSC time tag seconds are not valid: %s", err)
 	}
 	fractionalSeconds, remainingBytes, err := readOSCInt32(bytesAfterSeconds)
 	if err != nil {
-		return OSCTimeTag{}, bytes, err
+		return OSCTimeTag{}, bytes, fmt.Errorf("OSC time tag fractional seconds are not valid: %s", err)
 	}
 
 	return OSCTimeTag{
@@ -356,9 +435,16 @@ func readOSCArg(bytes []byte, oscType string) (OSCArg, []byte, error) {
 		}
 		oscArg.Value = argFloat
 		remainingBytes = bytesLeft
+	case "t":
+		argTimeTag, bytesLeft, err := readOSCTimeTag(bytes)
+		if err != nil {
+			readArgError = err
+		}
+		oscArg.Value = argTimeTag
+		remainingBytes = bytesLeft
 	default:
 		fmt.Printf("unsupported osc type: %s\n", oscType)
-		readArgError = errors.New("unsupported osc type: " + oscType)
+		readArgError = errors.New("unsupported OSC argument type: " + oscType)
 	}
 	return oscArg, remainingBytes, readArgError
 }

osc_test.go

@@ -0,0 +1,318 @@
+package osc
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestGoodOSCArgsToBuffer(t *testing.T) {
+
+	testCases := []struct {
+		name     string
+		args     []OSCArg
+		expected []byte
+	}{
+		{
+			name: "int arg",
+			args: []OSCArg{
+				{
+					Type:  "i",
+					Value: int(123),
+				},
+			},
+			expected: []byte{0, 0, 0, 123},
+		},
+		{
+			name: "int32 arg",
+			args: []OSCArg{
+				{
+					Type:  "i",
+					Value: int32(123),
+				},
+			},
+			expected: []byte{0, 0, 0, 123},
+		},
+		{
+			name: "float32 arg",
+			args: []OSCArg{
+				{
+					Type:  "f",
+					Value: float32(123),
+				},
+			},
+			expected: []byte{66, 246, 0, 0},
+		},
+		{
+			name: "float32 arg with int value",
+			args: []OSCArg{
+				{
+					Type:  "f",
+					Value: int(123),
+				},
+			},
+			expected: []byte{66, 246, 0, 0},
+		},
+		{
+			name: "float32 arg with int32 value",
+			args: []OSCArg{
+				{
+					Type:  "f",
+					Value: int32(123),
+				},
+			},
+			expected: []byte{66, 246, 0, 0},
+		},
+		{
+			name: "float32 arg with int64 value",
+			args: []OSCArg{
+				{
+					Type:  "f",
+					Value: int64(123),
+				},
+			},
+			expected: []byte{66, 246, 0, 0},
+		},
+		{
+			name: "float64 arg",
+			args: []OSCArg{
+				{
+					Type:  "d",
+					Value: float64(123),
+				},
+			},
+			expected: []byte{64, 94, 192, 0, 0, 0, 0, 0},
+		},
+		{
+			name: "float64 arg with float32 value",
+			args: []OSCArg{
+				{
+					Type:  "d",
+					Value: float32(123),
+				},
+			},
+			expected: []byte{64, 94, 192, 0, 0, 0, 0, 0},
+		},
+		{
+			name: "float64 arg with int value",
+			args: []OSCArg{
+				{
+					Type:  "d",
+					Value: int(123),
+				},
+			},
+			expected: []byte{64, 94, 192, 0, 0, 0, 0, 0},
+		},
+		{
+			name: "float64 arg with int32 value",
+			args: []OSCArg{
+				{
+					Type:  "d",
+					Value: int32(123),
+				},
+			},
+			expected: []byte{64, 94, 192, 0, 0, 0, 0, 0},
+		},
+		{
+			name: "float64 arg with int64 value",
+			args: []OSCArg{
+				{
+					Type:  "d",
+					Value: int64(123),
+				},
+			},
+			expected: []byte{64, 94, 192, 0, 0, 0, 0, 0},
+		},
+		{
+			name: "int64 arg",
+			args: []OSCArg{
+				{
+					Type:  "h",
+					Value: int64(123),
+				},
+			},
+			expected: []byte{0, 0, 0, 0, 0, 0, 0, 123},
+		},
+		{
+			name: "int64 arg with int32 value",
+			args: []OSCArg{
+				{
+					Type:  "h",
+					Value: int32(123),
+				},
+			},
+			expected: []byte{0, 0, 0, 0, 0, 0, 0, 123},
+		},
+		{
+			name: "blob arg",
+			args: []OSCArg{
+				{
+					Type:  "b",
+					Value: []byte{1, 2, 3},
+				},
+			},
+			expected: []byte{0, 0, 0, 3, 1, 2, 3, 0},
+		},
+		{
+			name: "true arg",
+			args: []OSCArg{
+				{
+					Type:  "T",
+					Value: true,
+				},
+			},
+			expected: []byte{},
+		},
+		{
+			name: "false arg",
+			args: []OSCArg{
+				{
+					Type:  "F",
+					Value: false,
+				},
+			},
+			expected: []byte{},
+		},
+		{
+			name: "nil arg",
+			args: []OSCArg{
+				{
+					Type:  "N",
+					Value: nil,
+				},
+			},
+			expected: []byte{},
+		},
+		{
+			name: "inifinitum arg",
+			args: []OSCArg{
+				{
+					Type:  "I",
+					Value: nil,
+				},
+			},
+			expected: []byte{},
+		},
+	}
+
+	for _, testCase := range testCases {
+		t.Run(testCase.name, func(t *testing.T) {
+
+			got, err := argsToBuffer(testCase.args)
+
+			if err != nil {
+				t.Fatalf("failed to encode properly: %s", err.Error())
+			}
+
+			if !reflect.DeepEqual(got, testCase.expected) {
+				t.Fatalf("failed to encode properly got '%v', expected '%v'", got, testCase.expected)
+			}
+		})
+	}
+}
+
+func TestBadOSCArgsToBuffer(t *testing.T) {
+
+	testCases := []struct {
+		name        string
+		args        []OSCArg
+		errorString string
+	}{}
+
+	for _, testCase := range testCases {
+		t.Run(testCase.name, func(t *testing.T) {
+
+			got, err := argsToBuffer(testCase.args)
+
+			if err == nil {
+				t.Fatalf("argsToBuffer expected to fail but got: %+v", got)
+			}
+
+			if err.Error() != testCase.errorString {
+				t.Fatalf("argsToBuffer got error '%s', expected '%s'", err.Error(), testCase.errorString)
+			}
+		})
+	}
+}
+
+func TestGoodPacketFromBytes(t *testing.T) {
+
+	testCases := []struct {
+		name     string
+		expected OSCPacket
+		bytes    []byte
+	}{
+		{
+			name: "message with no args",
+			expected: &OSCMessage{
+				Address: "/hello",
+				Args:    []OSCArg{},
+			},
+			bytes: []byte{47, 104, 101, 108, 108, 111, 0, 0},
+		},
+		{
+			name: "bundle with one message with no args",
+			expected: &OSCBundle{
+				TimeTag: OSCTimeTag{
+					seconds:           32,
+					fractionalSeconds: 0,
+				},
+				Contents: []OSCPacket{&OSCMessage{Address: "/oscillator/4/frequency", Args: []OSCArg{{Type: "f", Value: float32(440)}}}},
+			},
+			bytes: []byte{35, 98, 117, 110, 100, 108, 101, 0, 0, 0, 0,
+				32, 0, 0, 0, 0, 0, 0, 0, 32, 47, 111,
+				115, 99, 105, 108, 108, 97, 116, 111, 114, 47, 52,
+				47, 102, 114, 101, 113, 117, 101, 110, 99, 121, 0,
+				44, 102, 0, 0, 67, 220, 0, 0},
+		},
+	}
+
+	for _, testCase := range testCases {
+		t.Run(testCase.name, func(t *testing.T) {
+			got, remainingBytes, err := PacketFromBytes(testCase.bytes)
+
+			if err != nil {
+				t.Fatalf("failed to decode properly: %s", err.Error())
+			}
+
+			if len(remainingBytes) != 0 {
+				t.Fatalf("failed to decode properly, expected no remaining bytes but got: %v", remainingBytes)
+			}
+
+			if !reflect.DeepEqual(got, testCase.expected) {
+				t.Fatalf("failed to decode properly got '%v', expected '%v'", got, testCase.expected)
+			}
+		})
+	}
+}
+
+func TestBadPacketFromBytes(t *testing.T) {
+
+	testCases := []struct {
+		name        string
+		bytes       []byte
+		errorString string
+	}{
+		{name: "empty bytes",
+			bytes:       []byte{},
+			errorString: "cannot create OSC Packet from empty byte array",
+		},
+		{name: "packet that does not start with / or #",
+			bytes:       []byte{0, 1, 2, 3},
+			errorString: "OSC Packet must start with # for bundle or / for message",
+		},
+	}
+
+	for _, testCase := range testCases {
+		t.Run(testCase.name, func(t *testing.T) {
+			got, _, err := PacketFromBytes(testCase.bytes)
+
+			if err == nil {
+				t.Fatalf("PacketFromBytes expected to fail but got: %+v", got)
+			}
+
+			if err.Error() != testCase.errorString {
+				t.Fatalf("PacketFromBytes got error '%s', expected '%s'", err.Error(), testCase.errorString)
+			}
+		})
+	}
+}

types.go

@@ -1,7 +1,7 @@
 package osc
 
 type OSCPacket interface {
-	ToBytes() []byte
+	ToBytes() ([]byte, error)
 }
 
 type OSCBundle struct {