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ast/enum.go

@@ -108,7 +108,7 @@ type EnumValueDeclNode interface {
 }
 
 var _ EnumValueDeclNode = (*EnumValueNode)(nil)
-var _ EnumValueDeclNode = NoSourceNode{}
+var _ EnumValueDeclNode = (*NoSourceNode)(nil)
 
 // EnumValueNode represents an enum declaration. Example:
 //

ast/field.go

@@ -41,7 +41,7 @@ var _ FieldDeclNode = (*FieldNode)(nil)
 var _ FieldDeclNode = (*GroupNode)(nil)
 var _ FieldDeclNode = (*MapFieldNode)(nil)
 var _ FieldDeclNode = (*SyntheticMapField)(nil)
-var _ FieldDeclNode = NoSourceNode{}
+var _ FieldDeclNode = (*NoSourceNode)(nil)
 
 // FieldNode represents a normal field declaration (not groups or maps). It
 // can represent extension fields as well as non-extension fields (both inside
@@ -394,7 +394,7 @@ type OneofDeclNode interface {
 
 var _ OneofDeclNode = (*OneofNode)(nil)
 var _ OneofDeclNode = (*SyntheticOneof)(nil)
-var _ OneofDeclNode = NoSourceNode{}
+var _ OneofDeclNode = (*NoSourceNode)(nil)
 
 // OneofNode represents a one-of declaration. Example:
 //

ast/file.go

@@ -25,7 +25,7 @@ type FileDeclNode interface {
 }
 
 var _ FileDeclNode = (*FileNode)(nil)
-var _ FileDeclNode = NoSourceNode{}
+var _ FileDeclNode = (*NoSourceNode)(nil)
 
 // FileNode is the root of the AST hierarchy. It represents an entire
 // protobuf source file.

ast/message.go

@@ -32,7 +32,7 @@ type MessageDeclNode interface {
 var _ MessageDeclNode = (*MessageNode)(nil)
 var _ MessageDeclNode = (*SyntheticGroupMessageNode)(nil)
 var _ MessageDeclNode = (*SyntheticMapEntryNode)(nil)
-var _ MessageDeclNode = NoSourceNode{}
+var _ MessageDeclNode = (*NoSourceNode)(nil)
 
 // MessageNode represents a message declaration. Example:
 //

ast/no_source.go

@@ -41,104 +41,102 @@ func (s unknownSpan) End() SourcePos {
 // NoSourceNode is a placeholder AST node that implements numerous
 // interfaces in this package. It can be used to represent an AST
 // element for a file whose source is not available.
-type NoSourceNode struct {
-	filename string
-}
+type NoSourceNode FileInfo
 
 // NewNoSourceNode creates a new NoSourceNode for the given filename.
-func NewNoSourceNode(filename string) NoSourceNode {
-	return NoSourceNode{filename: filename}
+func NewNoSourceNode(filename string) *NoSourceNode {
+	return &NoSourceNode{name: filename}
 }
 
-func (n NoSourceNode) Name() string {
-	return n.filename
+func (n *NoSourceNode) Name() string {
+	return n.name
 }
 
-func (n NoSourceNode) Start() Token {
+func (n *NoSourceNode) Start() Token {
 	return 0
 }
 
-func (n NoSourceNode) End() Token {
+func (n *NoSourceNode) End() Token {
 	return 0
 }
 
-func (n NoSourceNode) NodeInfo(Node) NodeInfo {
+func (n *NoSourceNode) NodeInfo(Node) NodeInfo {
 	return NodeInfo{
-		fileInfo: &FileInfo{name: n.filename},
+		fileInfo: (*FileInfo)(n),
 	}
 }
 
-func (n NoSourceNode) GetSyntax() Node {
+func (n *NoSourceNode) GetSyntax() Node {
 	return n
 }
 
-func (n NoSourceNode) GetName() Node {
+func (n *NoSourceNode) GetName() Node {
 	return n
 }
 
-func (n NoSourceNode) GetValue() ValueNode {
+func (n *NoSourceNode) GetValue() ValueNode {
 	return n
 }
 
-func (n NoSourceNode) FieldLabel() Node {
+func (n *NoSourceNode) FieldLabel() Node {
 	return n
 }
 
-func (n NoSourceNode) FieldName() Node {
+func (n *NoSourceNode) FieldName() Node {
 	return n
 }
 
-func (n NoSourceNode) FieldType() Node {
+func (n *NoSourceNode) FieldType() Node {
 	return n
 }
 
-func (n NoSourceNode) FieldTag() Node {
+func (n *NoSourceNode) FieldTag() Node {
 	return n
 }
 
-func (n NoSourceNode) FieldExtendee() Node {
+func (n *NoSourceNode) FieldExtendee() Node {
 	return n
 }
 
-func (n NoSourceNode) GetGroupKeyword() Node {
+func (n *NoSourceNode) GetGroupKeyword() Node {
 	return n
 }
 
-func (n NoSourceNode) GetOptions() *CompactOptionsNode {
+func (n *NoSourceNode) GetOptions() *CompactOptionsNode {
 	return nil
 }
 
-func (n NoSourceNode) RangeStart() Node {
+func (n *NoSourceNode) RangeStart() Node {
 	return n
 }
 
-func (n NoSourceNode) RangeEnd() Node {
+func (n *NoSourceNode) RangeEnd() Node {
 	return n
 }
 
-func (n NoSourceNode) GetNumber() Node {
+func (n *NoSourceNode) GetNumber() Node {
 	return n
 }
 
-func (n NoSourceNode) MessageName() Node {
+func (n *NoSourceNode) MessageName() Node {
 	return n
 }
 
-func (n NoSourceNode) OneofName() Node {
+func (n *NoSourceNode) OneofName() Node {
 	return n
 }
 
-func (n NoSourceNode) GetInputType() Node {
+func (n *NoSourceNode) GetInputType() Node {
 	return n
 }
 
-func (n NoSourceNode) GetOutputType() Node {
+func (n *NoSourceNode) GetOutputType() Node {
 	return n
 }
 
-func (n NoSourceNode) Value() interface{} {
+func (n *NoSourceNode) Value() interface{} {
 	return nil
 }
 
-func (n NoSourceNode) RangeOptions(func(*OptionNode) bool) {
+func (n *NoSourceNode) RangeOptions(func(*OptionNode) bool) {
 }

ast/options.go

@@ -26,7 +26,7 @@ type OptionDeclNode interface {
 }
 
 var _ OptionDeclNode = (*OptionNode)(nil)
-var _ OptionDeclNode = NoSourceNode{}
+var _ OptionDeclNode = (*NoSourceNode)(nil)
 
 // OptionNode represents the declaration of a single option for an element.
 // It is used both for normal option declarations (start with "option" keyword
@@ -410,4 +410,4 @@ var _ NodeWithOptions = RPCDeclNode(nil)
 var _ NodeWithOptions = FieldDeclNode(nil)
 var _ NodeWithOptions = EnumValueDeclNode(nil)
 var _ NodeWithOptions = (*ExtensionRangeNode)(nil)
-var _ NodeWithOptions = NoSourceNode{}
+var _ NodeWithOptions = (*NoSourceNode)(nil)

ast/ranges.go

@@ -108,7 +108,7 @@ type RangeDeclNode interface {
 }
 
 var _ RangeDeclNode = (*RangeNode)(nil)
-var _ RangeDeclNode = NoSourceNode{}
+var _ RangeDeclNode = (*NoSourceNode)(nil)
 
 // RangeNode represents a range expression, used in both extension ranges and
 // reserved ranges. Example:

ast/service.go

@@ -108,7 +108,7 @@ type RPCDeclNode interface {
 }
 
 var _ RPCDeclNode = (*RPCNode)(nil)
-var _ RPCDeclNode = NoSourceNode{}
+var _ RPCDeclNode = (*NoSourceNode)(nil)
 
 // RPCNode represents an RPC declaration. Example:
 //

ast/values.go

@@ -54,7 +54,7 @@ var _ ValueNode = (*SpecialFloatLiteralNode)(nil)
 var _ ValueNode = (*SignedFloatLiteralNode)(nil)
 var _ ValueNode = (*ArrayLiteralNode)(nil)
 var _ ValueNode = (*MessageLiteralNode)(nil)
-var _ ValueNode = NoSourceNode{}
+var _ ValueNode = (*NoSourceNode)(nil)
 
 // StringValueNode is an AST node that represents a string literal.
 // Such a node can be a single literal (*StringLiteralNode) or a