Remove the "Unknown" constant

This commit replaces the Unknown constant with
separate constants for each enumeration that
uses it.

Fixes pion#1293

Author: wdouglass

Diff for: bundlepolicy.go

@@ -14,11 +14,14 @@ import (
 type BundlePolicy int
 
 const (
+	// BundlePolicyUnknown is the enum's zero-value
+	BundlePolicyUnknown BundlePolicy = iota
+
 	// BundlePolicyBalanced indicates to gather ICE candidates for each
 	// media type in use (audio, video, and data). If the remote endpoint is
 	// not bundle-aware, negotiate only one audio and video track on separate
 	// transports.
-	BundlePolicyBalanced BundlePolicy = iota + 1
+	BundlePolicyBalanced
 
 	// BundlePolicyMaxCompat indicates to gather ICE candidates for each
 	// track. If the remote endpoint is not bundle-aware, negotiate all media
@@ -47,7 +50,7 @@ func newBundlePolicy(raw string) BundlePolicy {
 	case bundlePolicyMaxBundleStr:
 		return BundlePolicyMaxBundle
 	default:
-		return BundlePolicy(Unknown)
+		return BundlePolicyUnknown
 	}
 }
 

Diff for: bundlepolicy_test.go

@@ -14,7 +14,7 @@ func TestNewBundlePolicy(t *testing.T) {
 		policyString   string
 		expectedPolicy BundlePolicy
 	}{
-		{unknownStr, BundlePolicy(Unknown)},
+		{ErrUnknownType.Error(), BundlePolicyUnknown},
 		{"balanced", BundlePolicyBalanced},
 		{"max-compat", BundlePolicyMaxCompat},
 		{"max-bundle", BundlePolicyMaxBundle},
@@ -34,7 +34,7 @@ func TestBundlePolicy_String(t *testing.T) {
 		policy         BundlePolicy
 		expectedString string
 	}{
-		{BundlePolicy(Unknown), unknownStr},
+		{BundlePolicyUnknown, ErrUnknownType.Error()},
 		{BundlePolicyBalanced, "balanced"},
 		{BundlePolicyMaxCompat, "max-compat"},
 		{BundlePolicyMaxBundle, "max-bundle"},

Diff for: constants.go

@@ -6,11 +6,6 @@ package webrtc
 import "github.com/pion/dtls/v2"
 
 const (
-	// Unknown defines default public constant to use for "enum" like struct
-	// comparisons when no value was defined.
-	Unknown    = iota
-	unknownStr = "unknown"
-
 	// Equal to UDP MTU
 	receiveMTU = 1460
 

Diff for: datachannelstate.go

@@ -7,10 +7,13 @@ package webrtc
 type DataChannelState int
 
 const (
+	// DataChannelStateUnknown is the enum's zero-value
+	DataChannelStateUnknown DataChannelState = iota
+
 	// DataChannelStateConnecting indicates that the data channel is being
 	// established. This is the initial state of DataChannel, whether created
 	// with CreateDataChannel, or dispatched as a part of an DataChannelEvent.
-	DataChannelStateConnecting DataChannelState = iota + 1
+	DataChannelStateConnecting
 
 	// DataChannelStateOpen indicates that the underlying data transport is
 	// established and communication is possible.
@@ -44,7 +47,7 @@ func newDataChannelState(raw string) DataChannelState {
 	case dataChannelStateClosedStr:
 		return DataChannelStateClosed
 	default:
-		return DataChannelState(Unknown)
+		return DataChannelStateUnknown
 	}
 }
 

Diff for: datachannelstate_test.go

@@ -14,7 +14,7 @@ func TestNewDataChannelState(t *testing.T) {
 		stateString   string
 		expectedState DataChannelState
 	}{
-		{unknownStr, DataChannelState(Unknown)},
+		{ErrUnknownType.Error(), DataChannelStateUnknown},
 		{"connecting", DataChannelStateConnecting},
 		{"open", DataChannelStateOpen},
 		{"closing", DataChannelStateClosing},
@@ -35,7 +35,7 @@ func TestDataChannelState_String(t *testing.T) {
 		state          DataChannelState
 		expectedString string
 	}{
-		{DataChannelState(Unknown), unknownStr},
+		{DataChannelStateUnknown, ErrUnknownType.Error()},
 		{DataChannelStateConnecting, "connecting"},
 		{DataChannelStateOpen, "open"},
 		{DataChannelStateClosing, "closing"},

Diff for: dtlsrole.go

@@ -11,10 +11,13 @@ import (
 type DTLSRole byte
 
 const (
+	// DTLSRoleUnknown is the enum's zero-value
+	DTLSRoleUnknown DTLSRole = iota
+
 	// DTLSRoleAuto defines the DTLS role is determined based on
 	// the resolved ICE role: the ICE controlled role acts as the DTLS
 	// client and the ICE controlling role acts as the DTLS server.
-	DTLSRoleAuto DTLSRole = iota + 1
+	DTLSRoleAuto
 
 	// DTLSRoleClient defines the DTLS client role.
 	DTLSRoleClient
@@ -51,7 +54,7 @@ func (r DTLSRole) String() string {
 	case DTLSRoleServer:
 		return "server"
 	default:
-		return unknownStr
+		return ErrUnknownType.Error()
 	}
 }
 

Diff for: dtlsrole_test.go

@@ -16,7 +16,7 @@ func TestDTLSRole_String(t *testing.T) {
 		role           DTLSRole
 		expectedString string
 	}{
-		{DTLSRole(Unknown), unknownStr},
+		{DTLSRoleUnknown, ErrUnknownType.Error()},
 		{DTLSRoleAuto, "auto"},
 		{DTLSRoleClient, "client"},
 		{DTLSRoleServer, "server"},

Diff for: dtlstransportstate.go

@@ -7,9 +7,12 @@ package webrtc
 type DTLSTransportState int
 
 const (
+	// DTLSTransportStateUnknown is the enum's zero-value
+	DTLSTransportStateUnknown DTLSTransportState = iota
+
 	// DTLSTransportStateNew indicates that DTLS has not started negotiating
 	// yet.
-	DTLSTransportStateNew DTLSTransportState = iota + 1
+	DTLSTransportStateNew
 
 	// DTLSTransportStateConnecting indicates that DTLS is in the process of
 	// negotiating a secure connection and verifying the remote fingerprint.
@@ -52,7 +55,7 @@ func newDTLSTransportState(raw string) DTLSTransportState {
 	case dtlsTransportStateFailedStr:
 		return DTLSTransportStateFailed
 	default:
-		return DTLSTransportState(Unknown)
+		return DTLSTransportStateUnknown
 	}
 }
 

Diff for: dtlstransportstate_test.go

@@ -14,7 +14,7 @@ func TestNewDTLSTransportState(t *testing.T) {
 		stateString   string
 		expectedState DTLSTransportState
 	}{
-		{unknownStr, DTLSTransportState(Unknown)},
+		{ErrUnknownType.Error(), DTLSTransportStateUnknown},
 		{"new", DTLSTransportStateNew},
 		{"connecting", DTLSTransportStateConnecting},
 		{"connected", DTLSTransportStateConnected},
@@ -36,7 +36,7 @@ func TestDTLSTransportState_String(t *testing.T) {
 		state          DTLSTransportState
 		expectedString string
 	}{
-		{DTLSTransportState(Unknown), unknownStr},
+		{DTLSTransportStateUnknown, ErrUnknownType.Error()},
 		{DTLSTransportStateNew, "new"},
 		{DTLSTransportStateConnecting, "connecting"},
 		{DTLSTransportStateConnected, "connected"},

Diff for: icecandidatetype.go

@@ -13,12 +13,15 @@ import (
 type ICECandidateType int
 
 const (
+	// ICECandidateTypeUnknown is the enum's zero-value
+	ICECandidateTypeUnknown ICECandidateType = iota
+
 	// ICECandidateTypeHost indicates that the candidate is of Host type as
 	// described in https://tools.ietf.org/html/rfc8445#section-5.1.1.1. A
 	// candidate obtained by binding to a specific port from an IP address on
 	// the host. This includes IP addresses on physical interfaces and logical
 	// ones, such as ones obtained through VPNs.
-	ICECandidateTypeHost ICECandidateType = iota + 1
+	ICECandidateTypeHost
 
 	// ICECandidateTypeSrflx indicates the the candidate is of Server
 	// Reflexive type as described
@@ -60,7 +63,7 @@ func NewICECandidateType(raw string) (ICECandidateType, error) {
 	case iceCandidateTypeRelayStr:
 		return ICECandidateTypeRelay, nil
 	default:
-		return ICECandidateType(Unknown), fmt.Errorf("%w: %s", errICECandidateTypeUnknown, raw)
+		return ICECandidateTypeUnknown, fmt.Errorf("%w: %s", errICECandidateTypeUnknown, raw)
 	}
 }
 
@@ -92,7 +95,7 @@ func getCandidateType(candidateType ice.CandidateType) (ICECandidateType, error)
 	default:
 		// NOTE: this should never happen[tm]
 		err := fmt.Errorf("%w: %s", errICEInvalidConvertCandidateType, candidateType.String())
-		return ICECandidateType(Unknown), err
+		return ICECandidateTypeUnknown, err
 	}
 }
 

Diff for: icecandidatetype_test.go

@@ -15,7 +15,7 @@ func TestICECandidateType(t *testing.T) {
 		shouldFail   bool
 		expectedType ICECandidateType
 	}{
-		{unknownStr, true, ICECandidateType(Unknown)},
+		{ErrUnknownType.Error(), true, ICECandidateTypeUnknown},
 		{"host", false, ICECandidateTypeHost},
 		{"srflx", false, ICECandidateTypeSrflx},
 		{"prflx", false, ICECandidateTypePrflx},
@@ -40,7 +40,7 @@ func TestICECandidateType_String(t *testing.T) {
 		cType          ICECandidateType
 		expectedString string
 	}{
-		{ICECandidateType(Unknown), unknownStr},
+		{ICECandidateTypeUnknown, ErrUnknownType.Error()},
 		{ICECandidateTypeHost, "host"},
 		{ICECandidateTypeSrflx, "srflx"},
 		{ICECandidateTypePrflx, "prflx"},

Diff for: icecomponent.go

@@ -8,12 +8,15 @@ package webrtc
 type ICEComponent int
 
 const (
+	// ICEComponentUnknown is the enum's zero-value
+	ICEComponentUnknown ICEComponent = iota
+
 	// ICEComponentRTP indicates that the ICE Transport is used for RTP (or
 	// RTCP multiplexing), as defined in
 	// https://tools.ietf.org/html/rfc5245#section-4.1.1.1. Protocols
 	// multiplexed with RTP (e.g. data channel) share its component ID. This
 	// represents the component-id value 1 when encoded in candidate-attribute.
-	ICEComponentRTP ICEComponent = iota + 1
+	ICEComponentRTP
 
 	// ICEComponentRTCP indicates that the ICE Transport is used for RTCP as
 	// defined by https://tools.ietf.org/html/rfc5245#section-4.1.1.1. This
@@ -34,7 +37,7 @@ func newICEComponent(raw string) ICEComponent {
 	case iceComponentRTCPStr:
 		return ICEComponentRTCP
 	default:
-		return ICEComponent(Unknown)
+		return ICEComponentUnknown
 	}
 }
 

Diff for: icecomponent_test.go

@@ -14,7 +14,7 @@ func TestICEComponent(t *testing.T) {
 		componentString   string
 		expectedComponent ICEComponent
 	}{
-		{unknownStr, ICEComponent(Unknown)},
+		{ErrUnknownType.Error(), ICEComponentUnknown},
 		{"rtp", ICEComponentRTP},
 		{"rtcp", ICEComponentRTCP},
 	}
@@ -33,7 +33,7 @@ func TestICEComponent_String(t *testing.T) {
 		state          ICEComponent
 		expectedString string
 	}{
-		{ICEComponent(Unknown), unknownStr},
+		{ICEComponentUnknown, ErrUnknownType.Error()},
 		{ICEComponentRTP, "rtp"},
 		{ICEComponentRTCP, "rtcp"},
 	}

Diff for: iceconnectionstate.go

@@ -7,11 +7,14 @@ package webrtc
 type ICEConnectionState int
 
 const (
+	// ICEConnectionStateUnknown is the enum's zero-value
+	ICEConnectionStateUnknown ICEConnectionState = iota
+
 	// ICEConnectionStateNew indicates that any of the ICETransports are
 	// in the "new" state and none of them are in the "checking", "disconnected"
 	// or "failed" state, or all ICETransports are in the "closed" state, or
 	// there are no transports.
-	ICEConnectionStateNew ICEConnectionState = iota + 1
+	ICEConnectionStateNew
 
 	// ICEConnectionStateChecking indicates that any of the ICETransports
 	// are in the "checking" state and none of them are in the "disconnected"
@@ -71,7 +74,7 @@ func NewICEConnectionState(raw string) ICEConnectionState {
 	case iceConnectionStateClosedStr:
 		return ICEConnectionStateClosed
 	default:
-		return ICEConnectionState(Unknown)
+		return ICEConnectionStateUnknown
 	}
 }
 

Diff for: iceconnectionstate_test.go

@@ -14,7 +14,7 @@ func TestNewICEConnectionState(t *testing.T) {
 		stateString   string
 		expectedState ICEConnectionState
 	}{
-		{unknownStr, ICEConnectionState(Unknown)},
+		{ErrUnknownType.Error(), ICEConnectionStateUnknown},
 		{"new", ICEConnectionStateNew},
 		{"checking", ICEConnectionStateChecking},
 		{"connected", ICEConnectionStateConnected},
@@ -38,7 +38,7 @@ func TestICEConnectionState_String(t *testing.T) {
 		state          ICEConnectionState
 		expectedString string
 	}{
-		{ICEConnectionState(Unknown), unknownStr},
+		{ICEConnectionStateUnknown, ErrUnknownType.Error()},
 		{ICEConnectionStateNew, "new"},
 		{ICEConnectionStateChecking, "checking"},
 		{ICEConnectionStateConnected, "connected"},

Diff for: icegathererstate.go

@@ -11,9 +11,12 @@ import (
 type ICEGathererState uint32
 
 const (
+	// ICEGathererStateUnknown is the enum's zero-value
+	ICEGathererStateUnknown ICEGathererState = iota
+
 	// ICEGathererStateNew indicates object has been created but
 	// gather() has not been called.
-	ICEGathererStateNew ICEGathererState = iota + 1
+	ICEGathererStateNew
 
 	// ICEGathererStateGathering indicates gather() has been called,
 	// and the ICEGatherer is in the process of gathering candidates.
@@ -38,7 +41,7 @@ func (s ICEGathererState) String() string {
 	case ICEGathererStateClosed:
 		return "closed"
 	default:
-		return unknownStr
+		return ErrUnknownType.Error()
 	}
 }
 

Diff for: icegathererstate_test.go

@@ -14,7 +14,7 @@ func TestICEGathererState_String(t *testing.T) {
 		state          ICEGathererState
 		expectedString string
 	}{
-		{ICEGathererState(Unknown), unknownStr},
+		{ICEGathererStateUnknown, ErrUnknownType.Error()},
 		{ICEGathererStateNew, "new"},
 		{ICEGathererStateGathering, "gathering"},
 		{ICEGathererStateComplete, "complete"},

Diff for: icegatheringstate.go

@@ -7,10 +7,13 @@ package webrtc
 type ICEGatheringState int
 
 const (
+	// ICEGatheringStateUnknown is the enum's zero-value
+	ICEGatheringStateUnknown ICEGatheringState = iota
+
 	// ICEGatheringStateNew indicates that any of the ICETransports are
 	// in the "new" gathering state and none of the transports are in the
 	// "gathering" state, or there are no transports.
-	ICEGatheringStateNew ICEGatheringState = iota + 1
+	ICEGatheringStateNew
 
 	// ICEGatheringStateGathering indicates that any of the ICETransports
 	// are in the "gathering" state.
@@ -38,7 +41,7 @@ func NewICEGatheringState(raw string) ICEGatheringState {
 	case iceGatheringStateCompleteStr:
 		return ICEGatheringStateComplete
 	default:
-		return ICEGatheringState(Unknown)
+		return ICEGatheringStateUnknown
 	}
 }
 

Diff for: icegatheringstate_test.go

@@ -14,7 +14,7 @@ func TestNewICEGatheringState(t *testing.T) {
 		stateString   string
 		expectedState ICEGatheringState
 	}{
-		{unknownStr, ICEGatheringState(Unknown)},
+		{ErrUnknownType.Error(), ICEGatheringStateUnknown},
 		{"new", ICEGatheringStateNew},
 		{"gathering", ICEGatheringStateGathering},
 		{"complete", ICEGatheringStateComplete},
@@ -34,7 +34,7 @@ func TestICEGatheringState_String(t *testing.T) {
 		state          ICEGatheringState
 		expectedString string
 	}{
-		{ICEGatheringState(Unknown), unknownStr},
+		{ICEGatheringStateUnknown, ErrUnknownType.Error()},
 		{ICEGatheringStateNew, "new"},
 		{ICEGatheringStateGathering, "gathering"},
 		{ICEGatheringStateComplete, "complete"},