rules.go

package protolock

import (
	"fmt"
)

var (
	// Rules provides a complete list of all funcs to be run to compare
	// a set of Protolocks. This list should be updated as new RuleFunc's
	// are added to this package.
	Rules = []Rule{
		{
			Name: "NoUsingReservedFields",
			Func: NoUsingReservedFields,
		},
		{
			Name: "NoRemovingReservedFields",
			Func: NoRemovingReservedFields,
		},
		{
			Name: "NoRemovingFieldsWithoutReserve",
			Func: NoRemovingFieldsWithoutReserve,
		},
		{
			Name: "NoChangingFieldIDs",
			Func: NoChangingFieldIDs,
		},
		{
			Name: "NoChangingFieldTypes",
			Func: NoChangingFieldTypes,
		},
		{
			Name: "NoChangingFieldNames",
			Func: NoChangingFieldNames,
		},
		{
			Name: "NoRemovingRPCs",
			Func: NoRemovingRPCs,
		},
		{
			Name: "NoChangingRPCSignature",
			Func: NoChangingRPCSignature,
		},
		{
			Name: "NoMovingExistingFieldsIntoOrOutOfOneof",
			Func: NoMovingExistingFieldsIntoOrOutOfOneof,
		},
	}

	strict = true
	debug  = false
)

const nestedPrefix = "."

// SetStrict enables the user to toggle strict mode on and off.
func SetStrict(mode bool) {
	strict = mode
}

// SetDebug enables the user to toggle debug mode on and off.
func SetDebug(status bool) {
	debug = status
}

type Rule struct {
	Name string
	Func RuleFunc
}

// RuleFunc defines the common signature for a function which can compare
// Protolock states and determine if issues exist.
type RuleFunc func(current, updated Protolock) ([]Warning, bool)

// lockIDsMap:
// table of filepath -> message name -> reserved field ID -> times ID encountered
// i.e.
/*
	["test.proto"] 	-> ["Test"] -> [1] -> 1

			-> ["User"] -> [1] -> 1
				       [2] -> 1
				       [3] -> 1

			-> ["Plan"] -> [1] -> 1
				       [2] -> 1
				       [3] -> 1
*/
type lockIDsMap map[Protopath]map[string]map[int]int

// lockNamesMap:
// table of filepath -> message name -> field name -> times name encountered (or the field ID)
// i.e.
/*
	["test.proto"]	->	["Test"]	->	["field_one"]	->	1
			-> 	["User"] 	-> 	["field_one"] 	-> 	1
							["field_two"] 	-> 	1
							["field_three"] -> 	1

			-> 	["Plan"] 	-> 	["field_one"] 	-> 	1
				       			["field_two"] 	-> 	1
				       			["field_three"] -> 	1
			# if mapping field name -> id,
			-> 	["Account"] 	-> 	["field_one"] 	-> 	1
						-> 	["field_two"] 	-> 	2
						-> 	["field_three"] -> 	3
*/
type lockNamesMap map[Protopath]map[string]map[string]int

// lockFieldMap:
// table of filepath -> message name -> field name -> field type
type lockFieldMap map[Protopath]map[string]map[string]Field

// lockEnumFieldMap:
// table of filepath -> message name -> field name -> enum field type
type lockEnumFieldMap map[Protopath]map[string]map[string]EnumField

// lockMapMap:
// table of filepath -> message name -> Map name -> Map type
type lockMapMap map[Protopath]map[string]map[string]Map

// lockRPCMap:
// table of filepath -> service name -> rpc name -> rpc type
type lockRPCMap map[Protopath]map[string]map[string]RPC

// lockFieldIDNameMap:
// table of filepath -> message name -> field ID -> field name
type lockFieldIDNameMap map[Protopath]map[string]map[int]string

func incMessageFields(reservedIDMap lockIDsMap, reservedNameMap lockNamesMap, filepath Protopath, prefix string, msg Message) {
	name := prefix + msg.Name
	for _, field := range msg.Fields {
		if reservedIDMap[filepath][name] == nil {
			reservedIDMap[filepath][name] = make(map[int]int)
		}
		if reservedNameMap[filepath][name] == nil {
			reservedNameMap[filepath][name] = make(map[string]int)
		}
		reservedIDMap[filepath][name][field.ID]++
		reservedNameMap[filepath][name][field.Name]++
	}
	for _, mp := range msg.Maps {
		if reservedIDMap[filepath][name] == nil {
			reservedIDMap[filepath][name] = make(map[int]int)
		}
		if reservedNameMap[filepath][name] == nil {
			reservedNameMap[filepath][name] = make(map[string]int)
		}
		reservedIDMap[filepath][name][mp.Field.ID]++
		reservedNameMap[filepath][name][mp.Field.Name]++
	}

	for _, m := range msg.Messages {
		incMessageFields(
			reservedIDMap, reservedNameMap,
			filepath, name+nestedPrefix, m,
		)
	}
}

func incEnumFields(reservedIDMap lockIDsMap, reservedNameMap lockNamesMap, filepath Protopath, enum Enum) {
	for _, field := range enum.EnumFields {
		if reservedIDMap[filepath][enum.Name] == nil {
			reservedIDMap[filepath][enum.Name] = make(map[int]int)
		}
		if reservedNameMap[filepath][enum.Name] == nil {
			reservedNameMap[filepath][enum.Name] = make(map[string]int)
		}

		for id := range reservedIDMap[filepath][enum.Name] {
			if field.Integer == id {
				reservedIDMap[filepath][enum.Name][field.Integer]++
			}
		}
		for name := range reservedNameMap[filepath][enum.Name] {
			if field.Name == name {
				reservedNameMap[filepath][enum.Name][field.Name]++
			}
		}
	}
}

// NoUsingReservedFields compares the current vs. updated Protolock definitions
// and will return a list of warnings if any message's previously reserved fields
// or IDs are now being used as part of the same message.
func NoUsingReservedFields(cur, upd Protolock) ([]Warning, bool) {
	reservedIDMap, reservedNameMap := getReservedFields(cur)
	reservedEnumIDMap, reservedEnumNameMap := getReservedEnumFields(cur)

	// add each messages field name/number to the existing list identified as
	// reserved to analyze
	for _, def := range upd.Definitions {
		if reservedIDMap[def.Filepath] == nil {
			reservedIDMap[def.Filepath] = make(map[string]map[int]int)
		}
		if reservedNameMap[def.Filepath] == nil {
			reservedNameMap[def.Filepath] = make(map[string]map[string]int)
		}
		for _, msg := range def.Def.Messages {
			incMessageFields(
				reservedIDMap, reservedNameMap,
				def.Filepath, "", msg,
			)
		}

		if reservedEnumIDMap[def.Filepath] == nil {
			reservedEnumIDMap[def.Filepath] = make(map[string]map[int]int)
		}
		if reservedEnumNameMap[def.Filepath] == nil {
			reservedEnumNameMap[def.Filepath] = make(map[string]map[string]int)
		}
		for _, enum := range def.Def.Enums {
			incEnumFields(
				reservedEnumIDMap, reservedEnumNameMap,
				def.Filepath, enum,
			)
		}
	}

	var warnings []Warning

	// Find message conflicts (using reserved names or IDs)

	// if the field ID was encountered more than once per message, then it
	// is known to be a re-use of a reserved field and a warning should be
	// returned for each occurrance
	for path, m := range reservedIDMap {
		for msgName, mm := range m {
			for id, count := range mm {
				if count > 1 {
					msg := fmt.Sprintf(
						`"%s" is re-using ID: %d, a reserved field number`,
						msgName, id,
					)
					warnings = append(warnings, Warning{
						Filepath: OSPath(path),
						Message:  msg,
					})
				}
			}
		}
	}
	// if the field name was encountered more than once per message, then it
	// is known to be a re-use of a reserved field and a warning should be
	// returned for each occurrance
	for path, m := range reservedNameMap {
		for msgName, mm := range m {
			for name, count := range mm {
				if count > 1 {
					msg := fmt.Sprintf(
						`"%s" is re-using name: "%s", a reserved field name`,
						msgName, name,
					)
					warnings = append(warnings, Warning{
						Filepath: OSPath(path),
						Message:  msg,
					})
				}
			}
		}
	}

	// Find enum conflicts (using reserved names or integers)

	// if the enum value was encountered more than once per message, then it
	// is known to be a re-use of a reserved field and a warning should be
	// returned for each occurrance
	for path, m := range reservedEnumIDMap {
		for enumName, mm := range m {
			for id, count := range mm {
				if count > 1 {
					msg := fmt.Sprintf(
						`"%s" is re-using integer: %d, a reserved value`,
						enumName, id,
					)
					warnings = append(warnings, Warning{
						Filepath: OSPath(path),
						Message:  msg,
					})
				}
			}
		}
	}
	// if the enum name was encountered more than once per message, then it
	// is known to be a re-use of a reserved field and a warning should be
	// returned for each occurrance
	for path, m := range reservedEnumNameMap {
		for enumName, mm := range m {
			for name, count := range mm {
				if count > 1 {
					msg := fmt.Sprintf(
						`"%s" is re-using name: "%s", a reserved name`,
						enumName, name,
					)
					warnings = append(warnings, Warning{
						Filepath: OSPath(path),
						Message:  msg,
					})
				}
			}
		}
	}

	if warnings != nil {
		return warnings, false
	}

	return nil, true
}

// NoRemovingReservedFields compares the current vs. updated Protolock definitions
// and will return a list of warnings if any reserved field has been removed. This
// rule is only enforced when strict mode is enabled.
func NoRemovingReservedFields(cur, upd Protolock) ([]Warning, bool) {
	if !strict {
		return nil, true
	}

	var warnings []Warning
	// check that all reserved fields on current Protolock remain in the
	// updated Protolock

	// check all reserved fields on messages
	curReservedIDMap, curReservedNameMap := getReservedFields(cur)
	updReservedIDMap, updReservedNameMap := getReservedFields(upd)
	for path, msgMap := range curReservedIDMap {
		for msgName, idMap := range msgMap {
			for id := range idMap {
				if _, ok := updReservedIDMap[path][msgName][id]; !ok {
					msg := fmt.Sprintf(
						`"%s" is missing ID: %d, which had been reserved`,
						msgName, id,
					)
					warnings = append(warnings, Warning{
						Filepath: OSPath(path),
						Message:  msg,
					})
				}
			}
		}
	}
	for path, msgMap := range curReservedNameMap {
		for msgName, nameMap := range msgMap {
			for name := range nameMap {
				if _, ok := updReservedNameMap[path][msgName][name]; !ok {
					msg := fmt.Sprintf(
						`"%s" is missing name: "%s", which had been reserved`,
						msgName, name,
					)
					warnings = append(warnings, Warning{
						Filepath: OSPath(path),
						Message:  msg,
					})
				}
			}
		}
	}

	// check all reserved fields on enums
	curReservedEnumIDMap, curReservedEnumNameMap := getReservedEnumFields(cur)
	updReservedEnumIDMap, updReservedEnumNameMap := getReservedEnumFields(upd)
	for path, enumMap := range curReservedEnumIDMap {
		for enumName, idMap := range enumMap {
			for id := range idMap {
				if _, ok := updReservedEnumIDMap[path][enumName][id]; !ok {
					msg := fmt.Sprintf(
						`"%s" is missing integer: %d, which had been reserved`,
						enumName, id,
					)
					warnings = append(warnings, Warning{
						Filepath: OSPath(path),
						Message:  msg,
					})
				}
			}
		}
	}
	for path, enumMap := range curReservedEnumNameMap {
		for enumName, nameMap := range enumMap {
			for name := range nameMap {
				if _, ok := updReservedEnumNameMap[path][enumName][name]; !ok {
					msg := fmt.Sprintf(
						`"%s" is missing name: "%s", which had been reserved`,
						enumName, name,
					)
					warnings = append(warnings, Warning{
						Filepath: OSPath(path),
						Message:  msg,
					})
				}
			}
		}
	}

	if warnings != nil {
		return warnings, false
	}

	return nil, true
}

// NoChangingFieldIDs compares the current vs. updated Protolock definitions and
// will return a list of warnings if any field ID number has been changed.
func NoChangingFieldIDs(cur, upd Protolock) ([]Warning, bool) {
	var warnings []Warning

	// check all non-reserved message fields
	curNameIDMap := getNonReservedFields(cur)
	updNameIDMap := getNonReservedFields(upd)

	// check that all current Protolock names map to the same IDs as the
	// updated Protolock
	for path, msgMap := range curNameIDMap {
		for msgName, fieldMap := range msgMap {
			for fieldName, fieldID := range fieldMap {
				updFieldID, ok := updNameIDMap[path][msgName][fieldName]
				if ok {
					if updFieldID != fieldID {
						msg := fmt.Sprintf(
							`"%s" field: "%s" has a different ID: %d, previously %d`,
							msgName, fieldName, updFieldID, fieldID,
						)
						warnings = append(warnings, Warning{
							Filepath: OSPath(path),
							Message:  msg,
						})
					}
				}
			}
		}
	}

	// check all non-reserved enum fields
	curEnumNameIDMap := getNonReservedEnumFields(cur)
	updEnumNameIDMap := getNonReservedEnumFields(upd)

	// check that all current Protolock names map to the same IDs as the
	// updated Protolock
	for path, enumMap := range curEnumNameIDMap {
		for enumName, fieldMap := range enumMap {
			for fieldName, fieldInteger := range fieldMap {
				updFieldInteger, ok := updEnumNameIDMap[path][enumName][fieldName]
				if ok {
					if updFieldInteger != fieldInteger {
						msg := fmt.Sprintf(
							`"%s" field: "%s" has a different integer: %d, previously %d`,
							enumName, fieldName, updFieldInteger, fieldInteger,
						)
						warnings = append(warnings, Warning{
							Filepath: OSPath(path),
							Message:  msg,
						})
					}
				}
			}
		}
	}

	if warnings != nil {
		return warnings, false
	}

	return nil, true
}

// NoChangingFieldTypes compares the current vs. updated Protolock definitions and
// will return a list of warnings if any field type has been changed.
func NoChangingFieldTypes(cur, upd Protolock) ([]Warning, bool) {
	curFieldMap := getFieldMap(cur)
	updFieldMap := getFieldMap(upd)
	curMapMap := getMapMap(cur)
	updMapMap := getMapMap(upd)
	var warnings []Warning
	// check that the current Protolock message's field types are the same
	// for each of the same message's fields in the updated Protolock
	for path, msgMap := range curFieldMap {
		for msgName, fieldMap := range msgMap {
			for fieldName, field := range fieldMap {
				updField, ok := updFieldMap[path][msgName][fieldName]
				if ok {
					if updField.Type != field.Type {
						msg := fmt.Sprintf(
							`"%s" field: "%s" has a different type: %s, previously %s`,
							msgName, fieldName, updField.Type, field.Type,
						)
						warnings = append(warnings, Warning{
							Filepath: OSPath(path),
							Message:  msg,
						})
					}

					if updField.IsRepeated != field.IsRepeated {
						msg := fmt.Sprintf(
							`"%s" field: "%s" has a different "repeated" status: %t, previously %t`,
							msgName, fieldName, updField.IsRepeated, field.IsRepeated,
						)
						warnings = append(warnings, Warning{
							Filepath: OSPath(path),
							Message:  msg,
						})
					}
				}
			}
		}
	}

	// check that the current Protolock message's map types are the same
	// for each of the same message's maps in the updated Protolock
	for path, msgMap := range curMapMap {
		for msgName, mapMap := range msgMap {
			for fieldName, mp := range mapMap {
				updMap, ok := updMapMap[path][msgName][fieldName]
				if ok {
					if updMap.KeyType != mp.KeyType {
						msg := fmt.Sprintf(
							`"%s" field: "%s" has a different type: %s, previously %s`,
							msgName, fieldName, updMap.KeyType, mp.KeyType,
						)
						warnings = append(warnings, Warning{
							Filepath: OSPath(path),
							Message:  msg,
						})
					}
				}
			}
		}
	}

	if warnings != nil {
		return warnings, false
	}

	return nil, true
}

// NoChangingFieldNames compares the current vs. updated Protolock definitions and
// will return a list of warnings if any message's previous fields have been
// renamed. This rule is only enforced when strict mode is enabled.
func NoChangingFieldNames(cur, upd Protolock) ([]Warning, bool) {
	if !strict {
		return nil, true
	}

	var warnings []Warning

	// check all field names of messages
	curFieldMap := getFieldsIDName(cur)
	updFieldMap := getFieldsIDName(upd)

	// check that the current Protolock messages' field names are equal to
	// their relative messages' field names in the updated Protolock
	for path, msgMap := range curFieldMap {
		for msgName, fieldMap := range msgMap {
			for fieldID, fieldName := range fieldMap {
				updFieldName, ok := updFieldMap[path][msgName][fieldID]
				if ok {
					if updFieldName != fieldName {
						msg := fmt.Sprintf(
							`"%s" field: "%s" ID: %d has an updated name, previously "%s"`,
							msgName, updFieldName, fieldID, fieldName,
						)
						warnings = append(warnings, Warning{
							Filepath: OSPath(path),
							Message:  msg,
						})
					}
				}
			}
		}
	}

	// check all field names of enums
	curEnumFieldMap := getEnumFieldsIDName(cur)
	updEnumFieldMap := getEnumFieldsIDName(upd)

	// check that the current Protolock enums' field names are equal to
	// their relative enums' field names in the updated Protolock
	for path, enumMap := range curEnumFieldMap {
		for enumName, fieldMap := range enumMap {
			for fieldInteger, fieldName := range fieldMap {
				updFieldName, ok := updEnumFieldMap[path][enumName][fieldInteger]
				if ok {
					if updFieldName != fieldName {
						msg := fmt.Sprintf(
							`"%s" field: "%s" integer: %d has an updated name, previously "%s"`,
							enumName, updFieldName, fieldInteger, fieldName,
						)
						warnings = append(warnings, Warning{
							Filepath: OSPath(path),
							Message:  msg,
						})
					}
				}
			}
		}
	}

	if warnings != nil {
		return warnings, false
	}

	return nil, true
}

// NoRemovingRPCs compares the current vs. updated Protolock definitions and
// will return a list of warnings if any RPCs provided by a Service have been
// removed. This rule is only enforced when strict mode is enabled.
func NoRemovingRPCs(cur, upd Protolock) ([]Warning, bool) {
	if !strict {
		return nil, true
	}

	var warnings []Warning
	// check that all current Protolock services' RPCs are still in the
	// updated Protolock
	curServices := getServicesRPCsMap(cur)
	updServices := getServicesRPCsMap(upd)

	for path, svcMap := range curServices {
		for svcName, rpcMap := range svcMap {
			for rpcName := range rpcMap {
				_, ok := updServices[path][svcName][rpcName]
				if !ok {
					msg := fmt.Sprintf(
						`"%s" is missing RPC: "%s", which should be available`,
						svcName, rpcName,
					)
					warnings = append(warnings, Warning{
						Filepath: OSPath(path),
						Message:  msg,
					})
				}
			}
		}
	}

	if warnings != nil {
		return warnings, false
	}

	return nil, true
}

// NoRemovingFieldsWithoutReserve compares the current vs. updated Protolock
// definitions and will return a list of warnings if any field has been removed
// without a corresponding reservation of that field name or ID.
func NoRemovingFieldsWithoutReserve(cur, upd Protolock) ([]Warning, bool) {
	var warnings []Warning

	// check all message fields
	curFieldMap := getFieldMap(cur)
	updFieldMap := getFieldMap(upd)

	// check that if a field name from the current Protolock is not retained
	// in the updated Protolock, then the field's name and ID should become
	// reserved within the parent message
	for path, msgMap := range curFieldMap {
		for msgName, fieldMap := range msgMap {
			encounteredIDs := make(map[int]int)
			for _, field := range updFieldMap[path][msgName] {
				encounteredIDs[field.ID]++
			}
			for fieldName, field := range fieldMap {
				_, ok := updFieldMap[path][msgName][fieldName]
				if !ok {
					// check that the field name and ID are
					// both in the reserved fields for this
					// message
					resIDsMap, resNamesMap := getReservedFields(upd)
					if _, ok := resNamesMap[path][msgName][field.Name]; !ok {
						msg := fmt.Sprintf(
							`"%s" field: "%s" has been removed, but is not reserved`,
							msgName, field.Name,
						)
						warnings = append(warnings, Warning{
							Filepath: OSPath(path),
							Message:  msg,
						})
					}

					// check that the ID for this missing field is being re-used
					// in which case will be caught by NoChangingFieldNames
					if _, ok := encounteredIDs[field.ID]; ok {
						continue
					}

					if _, ok := resIDsMap[path][msgName][field.ID]; !ok {
						msg := fmt.Sprintf(
							`"%s" ID: "%d" has been removed, but is not reserved`,
							msgName, field.ID,
						)
						warnings = append(warnings, Warning{
							Filepath: OSPath(path),
							Message:  msg,
						})
					}
				}
			}
		}
	}

	// check all enum fields
	curEnumFieldMap := getEnumFieldMap(cur)
	updEnumFieldMap := getEnumFieldMap(upd)

	// check that if a field name from the current Protolock is not retained
	// in the updated Protolock, then the field's name and integer should
	// become reserved within the parent enum
	for path, enumMap := range curEnumFieldMap {
		for enumName, fieldMap := range enumMap {
			encounteredIDs := make(map[int]int)
			for _, field := range updEnumFieldMap[path][enumName] {
				encounteredIDs[field.Integer]++
			}
			for fieldName, field := range fieldMap {
				_, ok := updEnumFieldMap[path][enumName][fieldName]
				if !ok {
					// check that the field name and ID are
					// both in the reserved fields for this
					// enum
					resIDsMap, resNamesMap := getReservedEnumFields(upd)
					if _, ok := resNamesMap[path][enumName][field.Name]; !ok {
						msg := fmt.Sprintf(
							`"%s" field: "%s" has been removed, but is not reserved`,
							enumName, field.Name,
						)
						warnings = append(warnings, Warning{
							Filepath: OSPath(path),
							Message:  msg,
						})
					}

					// check that the integer for this missing field is being re-used
					// in which case will be caught by NoChangingFieldNames
					if _, ok := encounteredIDs[field.Integer]; ok {
						continue
					}

					if _, ok := resIDsMap[path][enumName][field.Integer]; !ok {
						msg := fmt.Sprintf(
							`"%s" integer: "%d" has been removed, but is not reserved`,
							enumName, field.Integer,
						)
						warnings = append(warnings, Warning{
							Filepath: OSPath(path),
							Message:  msg,
						})
					}
				}
			}
		}
	}

	if warnings != nil {
		return warnings, false
	}

	return nil, true
}

// NoChangingRPCSignature compares the current vs. updated Protolock
// definitions and will return a list of warnings if any RPC signature has been
// changed while using the same name.
func NoChangingRPCSignature(cur, upd Protolock) ([]Warning, bool) {
	var warnings []Warning
	// check that no breaking changes to the signature of an RPC have been
	// made between the current Protolock and the updated Protolock
	curRPCMap := getRPCMap(cur)
	updRPCMap := getRPCMap(upd)
	for path, svcMap := range curRPCMap {
		for svcName, rpcMap := range svcMap {
			for rpcName, rpc := range rpcMap {
				updRPC, ok := updRPCMap[path][svcName][rpcName]
				if !ok {
					continue
				}

				// check that stream option and type are the same
				// for both the RPC's request and response
				if rpc.InStreamed != updRPC.InStreamed {
					msg := fmt.Sprintf(
						`"%s" RPC: "%s" input stream identifier has changed, previously: %t`,
						svcName, rpcName, rpc.InStreamed,
					)
					warnings = append(warnings, Warning{
						Filepath: OSPath(path),
						Message:  msg,
					})
				}

				if rpc.OutStreamed != updRPC.OutStreamed {
					msg := fmt.Sprintf(
						`"%s" RPC: "%s" output stream identifier has changed, previously: %t`,
						svcName, rpcName, rpc.OutStreamed,
					)
					warnings = append(warnings, Warning{
						Filepath: OSPath(path),
						Message:  msg,
					})
				}

				if rpc.InType != updRPC.InType {
					msg := fmt.Sprintf(
						`"%s" RPC: "%s" input type has changed, previously: %s`,
						svcName, rpcName, rpc.InType,
					)
					warnings = append(warnings, Warning{
						Filepath: OSPath(path),
						Message:  msg,
					})
				}

				if rpc.OutType != updRPC.OutType {
					msg := fmt.Sprintf(
						`"%s" RPC: "%s" output type has changed, previously: %s`,
						svcName, rpcName, rpc.OutType,
					)
					warnings = append(warnings, Warning{
						Filepath: OSPath(path),
						Message:  msg,
					})
				}
			}
		}
	}

	if warnings != nil {
		return warnings, false
	}

	return nil, true
}

// Existing fields must not be moved into or out of a oneof. This is a backwards-incompatible change in the Go protobuf stubs.
// per https://google.aip.dev/180#moving-into-oneofs
func NoMovingExistingFieldsIntoOrOutOfOneof(cur, upd Protolock) ([]Warning, bool) {
	var warnings []Warning

	// check all message fields
	curFieldMap := getFieldMap(cur)
	updFieldMap := getFieldMap(upd)

	// if a field name from the current Protolock has a OneofParent entry
	// that differs from the updated Protolock, then a warning should be added
	for path, msgMap := range curFieldMap {
		for msgName, fieldMap := range msgMap {
			for fieldName, field := range fieldMap {
				updField, ok := updFieldMap[path][msgName][fieldName]
				if ok && updField.OneofParent != field.OneofParent {
					if len(updField.OneofParent) == 0 {
						msg := fmt.Sprintf(
							`"%s" was moved out of oneof "%s"`,
							fieldName, field.OneofParent,
						)
						warnings = append(warnings, Warning{
							Filepath: OSPath(path),
							Message:  msg,
						})
					} else if len(field.OneofParent) == 0 {
						msg := fmt.Sprintf(
							`"%s" was moved into oneof "%s"`,
							fieldName, updField.OneofParent,
						)
						warnings = append(warnings, Warning{
							Filepath: OSPath(path),
							Message:  msg,
						})
					} else {
						msg := fmt.Sprintf(
							`"%s" was moved from oneof "%s" into of oneof "%s"`,
							fieldName, field.OneofParent, updField.OneofParent,
						)
						warnings = append(warnings, Warning{
							Filepath: OSPath(path),
							Message:  msg,
						})
					}
				}
			}
		}
	}

	if warnings != nil {
		return warnings, false
	}

	return nil, true
}

func getReservedFieldsRecursive(reservedIDMap lockIDsMap, reservedNameMap lockNamesMap, filepath Protopath, prefix string, msg Message) {
	msgName := prefix + msg.Name
	for _, id := range msg.ReservedIDs {
		if reservedIDMap[filepath][msgName] == nil {
			reservedIDMap[filepath][msgName] = make(map[int]int)
		}
		reservedIDMap[filepath][msgName][id]++
	}
	for _, name := range msg.ReservedNames {
		if reservedNameMap[filepath][msgName] == nil {
			reservedNameMap[filepath][msgName] = make(map[string]int)
		}
		reservedNameMap[filepath][msgName][name]++
	}

	for _, msg := range msg.Messages {
		// recursively call func, using parent message name and a '.' as prefix
		getReservedFieldsRecursive(reservedIDMap, reservedNameMap, filepath, msgName+nestedPrefix, msg)
	}
}

// getReservedFields gets all the reserved field numbers and names, and stashes
// them in a lockIDsMap and lockNamesMap to be checked against.
func getReservedFields(lock Protolock) (lockIDsMap, lockNamesMap) {
	reservedIDMap := make(lockIDsMap)
	reservedNameMap := make(lockNamesMap)

	for _, def := range lock.Definitions {
		if reservedIDMap[def.Filepath] == nil {
			reservedIDMap[def.Filepath] = make(map[string]map[int]int)
		}
		if reservedNameMap[def.Filepath] == nil {
			reservedNameMap[def.Filepath] = make(map[string]map[string]int)
		}

		for _, msg := range def.Def.Messages {
			getReservedFieldsRecursive(reservedIDMap, reservedNameMap, def.Filepath, "", msg)
		}
	}

	return reservedIDMap, reservedNameMap
}

func getReservedEnumFields(lock Protolock) (lockIDsMap, lockNamesMap) {
	reservedIDMap := make(lockIDsMap)
	reservedNameMap := make(lockNamesMap)

	for _, def := range lock.Definitions {
		if reservedIDMap[def.Filepath] == nil {
			reservedIDMap[def.Filepath] = make(map[string]map[int]int)
		}
		if reservedNameMap[def.Filepath] == nil {
			reservedNameMap[def.Filepath] = make(map[string]map[string]int)
		}

		for _, enum := range def.Def.Enums {
			for _, id := range enum.ReservedIDs {
				if reservedIDMap[def.Filepath][enum.Name] == nil {
					reservedIDMap[def.Filepath][enum.Name] = make(map[int]int)
				}
				reservedIDMap[def.Filepath][enum.Name][id]++
			}
			for _, name := range enum.ReservedNames {
				if reservedNameMap[def.Filepath][enum.Name] == nil {
					reservedNameMap[def.Filepath][enum.Name] = make(map[string]int)
				}
				reservedNameMap[def.Filepath][enum.Name][name]++
			}
		}
	}

	return reservedIDMap, reservedNameMap
}

func getFieldIDNameRecursive(fieldIDNameMap lockFieldIDNameMap, filepath Protopath, prefix string, msg Message) {
	msgName := prefix + msg.Name
	for _, field := range msg.Fields {
		if fieldIDNameMap[filepath][msgName] == nil {
			fieldIDNameMap[filepath][msgName] = make(map[int]string)
		}
		fieldIDNameMap[filepath][msgName][field.ID] = field.Name
	}
	for _, mp := range msg.Maps {
		if fieldIDNameMap[filepath][msgName] == nil {
			fieldIDNameMap[filepath][msgName] = make(map[int]string)
		}
		fieldIDNameMap[filepath][msgName][mp.Field.ID] = mp.Field.Name
	}
	for _, nestedMsg := range msg.Messages {
		getFieldIDNameRecursive(fieldIDNameMap, filepath, msgName+nestedPrefix, nestedMsg)
	}
}

// getFieldsIDName gets all the fields mapped by the field ID to its name for
// all messages.
func getFieldsIDName(lock Protolock) lockFieldIDNameMap {
	fieldIDNameMap := make(lockFieldIDNameMap)

	for _, def := range lock.Definitions {
		if fieldIDNameMap[def.Filepath] == nil {
			fieldIDNameMap[def.Filepath] = make(map[string]map[int]string)
		}
		for _, msg := range def.Def.Messages {
			getFieldIDNameRecursive(fieldIDNameMap, def.Filepath, "", msg)
		}
	}

	return fieldIDNameMap
}

// getEnumFieldsIDName gets all the fields mapped by the field ID to its name
// for all enums.
func getEnumFieldsIDName(lock Protolock) lockFieldIDNameMap {
	fieldIDNameMap := make(lockFieldIDNameMap)

	for _, def := range lock.Definitions {
		if fieldIDNameMap[def.Filepath] == nil {
			fieldIDNameMap[def.Filepath] = make(map[string]map[int]string)
		}
		for _, enum := range def.Def.Enums {
			for _, field := range enum.EnumFields {
				if fieldIDNameMap[def.Filepath][enum.Name] == nil {
					fieldIDNameMap[def.Filepath][enum.Name] = make(map[int]string)
				}
				fieldIDNameMap[def.Filepath][enum.Name][field.Integer] = field.Name
			}
		}
	}

	return fieldIDNameMap
}

func getNonReservedFieldsRecursive(nameIDMap lockNamesMap, filepath Protopath, prefix string, msg Message) {
	msgName := prefix + msg.Name
	for _, field := range msg.Fields {
		if nameIDMap[filepath][msgName] == nil {
			nameIDMap[filepath][msgName] = make(map[string]int)
		}
		nameIDMap[filepath][msgName][field.Name] = field.ID
	}
	for _, mp := range msg.Maps {
		if nameIDMap[filepath][msgName] == nil {
			nameIDMap[filepath][msgName] = make(map[string]int)
		}
		nameIDMap[filepath][msgName][mp.Field.Name] = mp.Field.ID
	}
	for _, nestedMsg := range msg.Messages {
		getNonReservedFieldsRecursive(nameIDMap, filepath, msgName+nestedPrefix, nestedMsg)
	}
}

// getNonReservedFields gets all the non-reserved field numbers and names, and
// stashes them in a lockNamesMap to be checked against.
func getNonReservedFields(lock Protolock) lockNamesMap {
	nameIDMap := make(lockNamesMap)

	for _, def := range lock.Definitions {
		if nameIDMap[def.Filepath] == nil {
			nameIDMap[def.Filepath] = make(map[string]map[string]int)
		}
		for _, msg := range def.Def.Messages {
			getNonReservedFieldsRecursive(nameIDMap, def.Filepath, "", msg)
		}
	}

	return nameIDMap
}

// getNonReservedEnumFields gets all the non-reserved field numbers and names,
// and stashes them in a lockNamesMap to be checked against.
func getNonReservedEnumFields(lock Protolock) lockNamesMap {
	nameIDMap := make(lockNamesMap)

	for _, def := range lock.Definitions {
		if nameIDMap[def.Filepath] == nil {
			nameIDMap[def.Filepath] = make(map[string]map[string]int)
		}
		for _, enum := range def.Def.Enums {
			for _, field := range enum.EnumFields {
				if nameIDMap[def.Filepath][enum.Name] == nil {
					nameIDMap[def.Filepath][enum.Name] = make(map[string]int)
				}
				nameIDMap[def.Filepath][enum.Name][field.Name] = field.Integer
			}
		}
	}

	return nameIDMap
}

func getMapMapRecursive(nameTypeMap lockMapMap, filepath Protopath, prefix string, msg Message) {
	msgName := prefix + msg.Name
	for _, mp := range msg.Maps {
		if nameTypeMap[filepath][msgName] == nil {
			nameTypeMap[filepath][msgName] = make(map[string]Map)
		}
		nameTypeMap[filepath][msgName][mp.Field.Name] = mp
	}
	for _, nestedMsg := range msg.Messages {

		getMapMapRecursive(nameTypeMap, filepath, msgName+nestedPrefix, nestedMsg)
	}
}

// getMapMap gets all the map names and types, and stashes them in a
// lockMapMap to be checked against.
func getMapMap(lock Protolock) lockMapMap {
	nameTypeMap := make(lockMapMap)

	for _, def := range lock.Definitions {
		if nameTypeMap[def.Filepath] == nil {
			nameTypeMap[def.Filepath] = make(map[string]map[string]Map)
		}
		for _, msg := range def.Def.Messages {
			getMapMapRecursive(nameTypeMap, def.Filepath, "", msg)
		}
	}

	return nameTypeMap
}

func getFieldMapRecursive(nameTypeMap lockFieldMap, filepath Protopath, prefix string, msg Message) {
	msgName := prefix + msg.Name
	for _, field := range msg.Fields {
		if nameTypeMap[filepath][msgName] == nil {
			nameTypeMap[filepath][msgName] = make(map[string]Field)
		}
		nameTypeMap[filepath][msgName][field.Name] = field
	}
	for _, mp := range msg.Maps {
		if nameTypeMap[filepath][msgName] == nil {
			nameTypeMap[filepath][msgName] = make(map[string]Field)
		}
		nameTypeMap[filepath][msgName][mp.Field.Name] = mp.Field
	}
	for _, nestedMsg := range msg.Messages {
		getFieldMapRecursive(nameTypeMap, filepath, msgName+nestedPrefix, nestedMsg)
	}
}

// getFieldMap gets all the field names and types, and stashes them in a
// lockFieldMap to be checked against.
func getFieldMap(lock Protolock) lockFieldMap {
	nameTypeMap := make(lockFieldMap)

	for _, def := range lock.Definitions {
		if nameTypeMap[def.Filepath] == nil {
			nameTypeMap[def.Filepath] = make(map[string]map[string]Field)
		}
		for _, msg := range def.Def.Messages {
			getFieldMapRecursive(nameTypeMap, def.Filepath, "", msg)
		}
	}

	return nameTypeMap
}

// getEnumFieldMap gets all the field names and types, and stashes them in a
// lockEnumFieldMap to be checked against.
func getEnumFieldMap(lock Protolock) lockEnumFieldMap {
	nameTypeMap := make(lockEnumFieldMap)

	for _, def := range lock.Definitions {
		if nameTypeMap[def.Filepath] == nil {
			nameTypeMap[def.Filepath] = make(map[string]map[string]EnumField)
		}
		for _, enum := range def.Def.Enums {
			for _, field := range enum.EnumFields {
				if nameTypeMap[def.Filepath][enum.Name] == nil {
					nameTypeMap[def.Filepath][enum.Name] = make(map[string]EnumField)
				}
				nameTypeMap[def.Filepath][enum.Name][field.Name] = field
			}
		}
	}

	return nameTypeMap
}

// getServicesRPCsMap gets all the RPCs for the Services in a Protolock and
// stashes them in a lockNamesMap to be checked against.
func getServicesRPCsMap(lock Protolock) lockNamesMap {
	servicesRPCsMap := make(lockNamesMap)
	for _, def := range lock.Definitions {
		if servicesRPCsMap[def.Filepath] == nil {
			servicesRPCsMap[def.Filepath] = make(map[string]map[string]int)
		}
		for _, svc := range def.Def.Services {
			if servicesRPCsMap[def.Filepath][svc.Name] == nil {
				servicesRPCsMap[def.Filepath][svc.Name] = make(map[string]int)
			}
			for _, rpc := range svc.RPCs {
				servicesRPCsMap[def.Filepath][svc.Name][rpc.Name]++
			}
		}
	}

	return servicesRPCsMap
}

// getRPCMap gets all the RPC names and types, and stashes them in a
// lockRPCMap to be checked against.
func getRPCMap(lock Protolock) lockRPCMap {
	rpcTypeMap := make(lockRPCMap)

	for _, def := range lock.Definitions {
		if rpcTypeMap[def.Filepath] == nil {
			rpcTypeMap[def.Filepath] = make(map[string]map[string]RPC)
		}
		for _, svc := range def.Def.Services {
			for _, rpc := range svc.RPCs {
				if rpcTypeMap[def.Filepath][svc.Name] == nil {
					rpcTypeMap[def.Filepath][svc.Name] = make(map[string]RPC)
				}
				rpcTypeMap[def.Filepath][svc.Name][rpc.Name] = rpc
			}
		}
	}

	return rpcTypeMap
}

func beginRuleDebug(name string) {
	fmt.Println("RUN RULE:", name)
}

func concludeRuleDebug(name string, warnings []Warning) {
	fmt.Println("# Warnings:", len(warnings))
	for i, w := range warnings {
		msg := fmt.Sprintf("%d). %s [%s]", i+1, w.Message, w.Filepath)
		fmt.Println(msg)
	}
	fmt.Println("END RULE:", name)
	fmt.Println("===")
}