encoding/jsonschema: remove unused state fields

The presence of both `state.parent` and `state.up` was confusing,
especially as neither was documented and `state.parent` wasn't actually
used for anything.

Likewise, `state.path` isn't used for anything, and isn't actually an
accurate reflection of the JSON path (it's not updated for list values).

So remove both. They can easily be reinstated if they turn out to be
useful in the future.

Signed-off-by: Roger Peppe <[email protected]>
Change-Id: Ice08453b867f4e6a474db1e725e59b99e22ce036
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1202558
TryBot-Result: CUEcueckoo <[email protected]>
Unity-Result: CUE porcuepine <[email protected]>
Reviewed-by: Daniel Martí <[email protected]>

encoding/jsonschema/constraints_combinator.go

@@ -33,7 +33,7 @@ func constraintAllOf(key string, n cue.Value, s *state) {
 	}
 	a := make([]ast.Expr, 0, len(items))
 	for _, v := range items {
-		x, sub := s.schemaState(v, s.allowedTypes, nil, true)
+		x, sub := s.schemaState(v, s.allowedTypes, nil)
 		s.allowedTypes &= sub.allowedTypes
 		if sub.hasConstraints() {
 			// This might seem a little odd, since the actual
@@ -74,7 +74,7 @@ func constraintAnyOf(key string, n cue.Value, s *state) {
 	}
 	a := make([]ast.Expr, 0, len(items))
 	for _, v := range items {
-		x, sub := s.schemaState(v, s.allowedTypes, nil, true)
+		x, sub := s.schemaState(v, s.allowedTypes, nil)
 		if sub.allowedTypes == 0 {
 			// Nothing is allowed; omit.
 			continue
@@ -118,7 +118,7 @@ func constraintOneOf(key string, n cue.Value, s *state) {
 	}
 	a := make([]ast.Expr, 0, len(items))
 	for _, v := range items {
-		x, sub := s.schemaState(v, s.allowedTypes, nil, true)
+		x, sub := s.schemaState(v, s.allowedTypes, nil)
 		if sub.allowedTypes == 0 {
 			// Nothing is allowed; omit
 			continue

encoding/jsonschema/constraints_object.go

@@ -107,7 +107,7 @@ func constraintProperties(key string, n cue.Value, s *state) {
 	s.processMap(n, func(key string, n cue.Value) {
 		// property?: value
 		name := ast.NewString(key)
-		expr, state := s.schemaState(n, allTypes, []label{{name: key}}, false)
+		expr, state := s.schemaState(n, allTypes, []label{{name: key}})
 		f := &ast.Field{Label: name, Value: expr}
 		state.doc(f)
 		f.Optional = token.Blank.Pos()
@@ -131,7 +131,7 @@ func constraintProperties(key string, n cue.Value, s *state) {
 
 func constraintPropertyNames(key string, n cue.Value, s *state) {
 	// [=~pattern]: _
-	if names, _ := s.schemaState(n, cue.StringKind, nil, false); !isAny(names) {
+	if names, _ := s.schemaState(n, cue.StringKind, nil); !isAny(names) {
 		x := ast.NewStruct(ast.NewList(names), top())
 		s.add(n, objectType, x)
 	}

encoding/jsonschema/decode.go

@@ -125,7 +125,7 @@ func (d *decoder) schema(ref []ast.Label, v cue.Value) (a []ast.Decl) {
 		root.isSchema = true
 	}
 
-	expr, state := root.schemaState(v, allTypes, nil, false)
+	expr, state := root.schemaState(v, allTypes, nil)
 	if state.allowedTypes == 0 {
 		d.addErr(errors.Newf(state.pos.Pos(), "constraints are not possible to satisfy"))
 	}
@@ -378,8 +378,7 @@ type state struct {
 
 	isSchema bool // for omitting ellipsis in an ast.File
 
-	up     *state
-	parent *state
+	up *state
 
 	path []string
 
@@ -685,7 +684,7 @@ func (s *state) doc(n ast.Node) {
 }
 
 func (s *state) schema(n cue.Value, idRef ...label) ast.Expr {
-	expr, _ := s.schemaState(n, allTypes, idRef, false)
+	expr, _ := s.schemaState(n, allTypes, idRef)
 	// TODO: report unused doc.
 	return expr
 }
@@ -695,21 +694,17 @@ func (s *state) schema(n cue.Value, idRef ...label) ast.Expr {
 // types holds the set of possible types that the value can hold.
 // idRef holds the path to the value.
 // isLogical specifies whether the caller is a logical operator like anyOf, allOf, oneOf, or not.
-func (s *state) schemaState(n cue.Value, types cue.Kind, idRef []label, isLogical bool) (ast.Expr, *state) {
+func (s *state) schemaState(n cue.Value, types cue.Kind, idRef []label) (ast.Expr, *state) {
 	state := &state{
 		up:            s,
 		schemaVersion: s.schemaVersion,
 		isSchema:      s.isSchema,
 		decoder:       s.decoder,
 		allowedTypes:  types,
 		knownTypes:    allTypes,
-		path:          s.path,
 		idRef:         idRef,
 		pos:           n,
 	}
-	if isLogical {
-		state.parent = s
-	}
 	if n.Kind() == cue.BoolKind {
 		if vfrom(VersionDraft6).contains(state.schemaVersion) {
 			// From draft6 onwards, boolean values signify a schema that always passes or fails.
@@ -796,14 +791,10 @@ func (s *state) value(n cue.Value) ast.Expr {
 // This may also prevent exponential blow-up (as may happen when
 // converting YAML to JSON).
 func (s *state) processMap(n cue.Value, f func(key string, n cue.Value)) {
-	saved := s.path
-	defer func() { s.path = saved }()
 
 	// TODO: intercept references to allow for optimized performance.
 	for i, _ := n.Fields(); i.Next(); {
-		key := i.Label()
-		s.path = append(saved, key)
-		f(key, i.Value())
+		f(i.Label(), i.Value())
 	}
 }