Fix up some style violations

sdks/go/pkg/beam/core/funcx/fn.go

@@ -83,7 +83,7 @@ const (
 	FnBundleFinalization FnParamKind = 0x800
 	// FnWatermarkEstimator indicates a function input parameter that implements sdf.WatermarkEstimator
 	FnWatermarkEstimator FnParamKind = 0x1000
-	// FnState indicates a function input parameter that implements state.Provider
+	// FnStateProvider indicates a function input parameter that implements state.Provider
 	FnStateProvider FnParamKind = 0x2000
 )
 

sdks/go/pkg/beam/core/graph/fn.go

@@ -1272,15 +1272,10 @@ func validateState(fn *DoFn, numIn mainInputs) error {
 				err := errors.Errorf("Duplicate state key %v", k)
 				return errors.SetTopLevelMsgf(err, "Duplicate state key %v used by %v and %v. Ensure that state keys are"+
 					"unique per DoFn", k, orig, s)
-			} else {
-				stateKeys[k] = s
 			}
-		}
 
-		// TODO(#22736) - Remove this once state is fully supported
-		err := errors.Errorf("ProcessElement uses a StateProvider, but state is not supported in this release.")
-		return errors.SetTopLevelMsgf(err, "ProcessElement uses a StateProvider, but state is not supported in this release. "+
-			"Please try upgrading to a newer release if one exists or wait for state support to be released.")
+			stateKeys[k] = s
+		}
 	} else {
 		if len(ps) > 0 {
 			err := errors.Errorf("ProcessElement doesn't use a StateProvider, but State structs are attached to "+
@@ -1291,6 +1286,13 @@ func validateState(fn *DoFn, numIn mainInputs) error {
 		}
 	}
 
+	if len(ps) > 0 {
+		// TODO(#22736) - Remove this once state is fully supported
+		err := errors.Errorf("ProcessElement uses a StateProvider, but state is not supported in this release.")
+		return errors.SetTopLevelMsgf(err, "ProcessElement uses a StateProvider, but state is not supported in this release. "+
+			"Please try upgrading to a newer release if one exists or wait for state support to be released.")
+	}
+
 	return nil
 }
 

sdks/go/pkg/beam/core/runtime/exec/fn.go

@@ -73,15 +73,15 @@ type stateProvider struct {
 }
 
 // ReadValueState reads a value state from the State API
-func (s *stateProvider) ReadValueState(userStateId string) (interface{}, []state.Transaction, error) {
+func (s *stateProvider) ReadValueState(userStateID string) (interface{}, []state.Transaction, error) {
 	// TODO(#22736) - read from the state api.
-	return nil, nil, errors.New("Stateful DoFns are not supported yet.")
+	return nil, nil, errors.New("stateful DoFns are not supported yet")
 }
 
 // WriteValueState writes a value state to the State API
 func (s *stateProvider) WriteValueState(val state.Transaction) error {
 	// TODO(#22736) - read from the state api.
-	return errors.New("Stateful DoFns are not supported yet.")
+	return errors.New("stateful DoFns are not supported yet")
 }
 
 // Invoke invokes the fn with the given values. The extra values must match the non-main

sdks/go/pkg/beam/core/runtime/exec/translate.go

@@ -466,15 +466,15 @@ func (b *builder) makeLink(from string, id linkID) (Node, error) {
 					input := unmarshalKeyedValues(transform.GetInputs())
 
 					if len(userState) > 0 {
-						stateIdToCoder := make(map[string]*coder.Coder)
+						stateIDToCoder := make(map[string]*coder.Coder)
 						for key, spec := range userState {
 							// TODO(#22736) - this will eventually need to be aware of which type of state its modifying to support non-Value state types.
 							cID := spec.GetReadModifyWriteSpec().CoderId
 							c, err := b.coders.Coder(cID)
 							if err != nil {
 								return nil, err
 							}
-							stateIdToCoder[key] = c
+							stateIDToCoder[key] = c
 						}
 					}
 

sdks/go/pkg/beam/core/runtime/graphx/translate.go

@@ -462,7 +462,7 @@ func (m *marshaller) addMultiEdge(edge NamedEdge) ([]string, error) {
 			m.requirements[URNRequiresStatefulProcessing] = true
 			stateSpecs := make(map[string]*pipepb.StateSpec)
 			for _, ps := range edge.Edge.DoFn.PipelineState() {
-				coderId, err := m.coders.Add(edge.Edge.StateCoders[ps.StateKey()])
+				coderID, err := m.coders.Add(edge.Edge.StateCoders[ps.StateKey()])
 				if err != nil {
 					return handleErr(err)
 				}
@@ -471,7 +471,7 @@ func (m *marshaller) addMultiEdge(edge NamedEdge) ([]string, error) {
 					// See https://github.com/apache/beam/blob/54b0784da7ccba738deff22bd83fbc374ad21d2e/sdks/go/pkg/beam/model/pipeline_v1/beam_runner_api.pb.go#L2635
 					Spec: &pipepb.StateSpec_ReadModifyWriteSpec{
 						ReadModifyWriteSpec: &pipepb.ReadModifyWriteStateSpec{
-							CoderId: coderId,
+							CoderId: coderID,
 						},
 					},
 					Protocol: &pipepb.FunctionSpec{

sdks/go/pkg/beam/core/state/state.go

@@ -20,14 +20,16 @@ import (
 	"reflect"
 )
 
-type TransactionType_Enum int32
+// TransactionTypeEnum represents the type of state manipulation being done (e.g. set, clear, etc...)
+type TransactionTypeEnum int32
 
 const (
-	TransactionType_Set   TransactionType_Enum = 0
-	TransactionType_Clear TransactionType_Enum = 1
+	TransactionTypeSet   TransactionTypeEnum = 0
+	TransactionTypeClear TransactionTypeEnum = 1
 )
 
 var (
+	// ProviderType is the reflected type of state.Provider
 	ProviderType = reflect.TypeOf((*Provider)(nil)).Elem()
 )
 
@@ -37,7 +39,7 @@ var (
 // it is primarily used for implementations of the Provider interface to talk to the various State objects.
 type Transaction struct {
 	Key  string
-	Type TransactionType_Enum
+	Type TransactionTypeEnum
 	Val  interface{}
 }
 
@@ -67,7 +69,7 @@ type Value[T any] struct {
 func (s *Value[T]) Write(p Provider, val T) error {
 	return p.WriteValueState(Transaction{
 		Key:  s.Key,
-		Type: TransactionType_Set,
+		Type: TransactionTypeSet,
 		Val:  val,
 	})
 }
@@ -84,9 +86,9 @@ func (s *Value[T]) Read(p Provider) (T, bool, error) {
 	}
 	for _, t := range bufferedTransactions {
 		switch t.Type {
-		case TransactionType_Set:
+		case TransactionTypeSet:
 			cur = t.Val
-		case TransactionType_Clear:
+		case TransactionTypeClear:
 			cur = nil
 		}
 	}

sdks/go/pkg/beam/core/state/state_test.go

@@ -30,12 +30,12 @@ type fakeProvider struct {
 	err          map[string]error
 }
 
-func (s *fakeProvider) ReadValueState(userStateId string) (interface{}, []Transaction, error) {
-	if err, ok := s.err[userStateId]; ok {
+func (s *fakeProvider) ReadValueState(userStateID string) (interface{}, []Transaction, error) {
+	if err, ok := s.err[userStateID]; ok {
 		return nil, nil, err
 	}
-	base := s.initialState[userStateId]
-	trans, ok := s.transactions[userStateId]
+	base := s.initialState[userStateID]
+	trans, ok := s.transactions[userStateID]
 	if !ok {
 		trans = []Transaction{}
 	}
@@ -58,15 +58,15 @@ func TestValueRead(t *testing.T) {
 	is["no_transactions"] = 1
 	ts["no_transactions"] = nil
 	is["basic_set"] = 1
-	ts["basic_set"] = []Transaction{{Key: "basic_set", Type: TransactionType_Set, Val: 3}}
+	ts["basic_set"] = []Transaction{{Key: "basic_set", Type: TransactionTypeSet, Val: 3}}
 	is["basic_clear"] = 1
-	ts["basic_clear"] = []Transaction{{Key: "basic_clear", Type: TransactionType_Clear, Val: nil}}
+	ts["basic_clear"] = []Transaction{{Key: "basic_clear", Type: TransactionTypeClear, Val: nil}}
 	is["set_then_clear"] = 1
-	ts["set_then_clear"] = []Transaction{{Key: "set_then_clear", Type: TransactionType_Set, Val: 3}, {Key: "set_then_clear", Type: TransactionType_Clear, Val: nil}}
+	ts["set_then_clear"] = []Transaction{{Key: "set_then_clear", Type: TransactionTypeSet, Val: 3}, {Key: "set_then_clear", Type: TransactionTypeClear, Val: nil}}
 	is["set_then_clear_then_set"] = 1
-	ts["set_then_clear_then_set"] = []Transaction{{Key: "set_then_clear_then_set", Type: TransactionType_Set, Val: 3}, {Key: "set_then_clear_then_set", Type: TransactionType_Clear, Val: nil}, {Key: "set_then_clear_then_set", Type: TransactionType_Set, Val: 4}}
+	ts["set_then_clear_then_set"] = []Transaction{{Key: "set_then_clear_then_set", Type: TransactionTypeSet, Val: 3}, {Key: "set_then_clear_then_set", Type: TransactionTypeClear, Val: nil}, {Key: "set_then_clear_then_set", Type: TransactionTypeSet, Val: 4}}
 	is["err"] = 1
-	ts["err"] = []Transaction{{Key: "err", Type: TransactionType_Set, Val: 3}}
+	ts["err"] = []Transaction{{Key: "err", Type: TransactionTypeSet, Val: 3}}
 	es["err"] = errFake
 
 	f := fakeProvider{