Remove placeholder nodes

Author: kimdv

CodeGeneration/Sources/SyntaxSupport/DeclNodes.swift

@@ -548,39 +548,6 @@ public let DECL_NODES: [Node] = [
     elementChoices: [.designatedType]
   ),
 
-  Node(
-    kind: .editorPlaceholderDecl,
-    base: .decl,
-    nameForDiagnostics: "editor placeholder",
-    documentation: """
-      An editor placeholder, e.g. `<#declaration#>` that is used in a position that expects a declaration.
-      """,
-    traits: [
-      "WithAttributes",
-      "WithModifiers",
-    ],
-    children: [
-      Child(
-        name: "attributes",
-        kind: .collection(kind: .attributeList, collectionElementName: "Attribute", defaultsToEmpty: true),
-        documentation: "If there were attributes before the editor placeholder, the ``EditorPlaceholderDeclSyntax`` will contain these."
-      ),
-      Child(
-        name: "modifiers",
-        kind: .collection(kind: .declModifierList, collectionElementName: "Modifier", defaultsToEmpty: true),
-        documentation: "If there were modifiers before the editor placeholder, the `EditorPlaceholderDecl` will contain these."
-      ),
-      Child(
-        name: "placeholder",
-        deprecatedName: "identifier",
-        kind: .token(choices: [.token(.identifier)]),
-        documentation: """
-          The actual editor placeholder that starts with `<#` and ends with `#>`.
-          """
-      ),
-    ]
-  ),
-
   Node(
     kind: .enumCaseParameterClause,
     base: .syntax,

CodeGeneration/Sources/SyntaxSupport/ExprNodes.swift

@@ -740,19 +740,6 @@ public let EXPR_NODES: [Node] = [
     ]
   ),
 
-  Node(
-    kind: .editorPlaceholderExpr,
-    base: .expr,
-    nameForDiagnostics: "editor placeholder",
-    children: [
-      Child(
-        name: "placeholder",
-        deprecatedName: "identifier",
-        kind: .token(choices: [.token(.identifier)])
-      )
-    ]
-  ),
-
   Node(
     kind: .exprList,
     base: .syntaxCollection,

CodeGeneration/Sources/SyntaxSupport/SyntaxNodeKind.swift

@@ -109,8 +109,6 @@ public enum SyntaxNodeKind: String, CaseIterable {
   case documentationAttributeArgumentList
   case doStmt
   case dynamicReplacementAttributeArguments
-  case editorPlaceholderDecl
-  case editorPlaceholderExpr
   case effectsAttributeArgumentList
   case enumCaseDecl
   case enumCaseElement

Sources/SwiftParser/Declarations.swift

@@ -275,9 +275,9 @@ extension Parser {
       }
 
       if self.currentToken.isEditorPlaceholder {
-        let placeholder = self.consumeAnyToken()
+        let placeholder = self.parseAnyIdentifier()
         return RawDeclSyntax(
-          RawEditorPlaceholderDeclSyntax(
+          RawMissingDeclSyntax(
             attributes: attrs.attributes,
             modifiers: attrs.modifiers,
             placeholder: placeholder,

Sources/SwiftParser/Expressions.swift

@@ -1242,14 +1242,6 @@ extension Parser {
   mutating func parseIdentifierExpression() -> RawExprSyntax {
     let declName = self.parseDeclReferenceExpr(.compoundNames)
     guard self.withLookahead({ $0.canParseAsGenericArgumentList() }) else {
-      if declName.baseName.tokenText.isEditorPlaceholder && declName.argumentNames == nil {
-        return RawExprSyntax(
-          RawEditorPlaceholderExprSyntax(
-            placeholder: declName.baseName,
-            arena: self.arena
-          )
-        )
-      }
       return RawExprSyntax(declName)
     }
 

Sources/SwiftParserDiagnostics/MissingNodesError.swift

@@ -381,7 +381,17 @@ extension ParseDiagnosticsGenerator {
 
     // Walk all upcoming sibling to see if they are also missing to handle them in this diagnostic.
     // If this is the case, handle all of them in this diagnostic.
-    var missingNodes = [Syntax(node)]
+    var missingNodes: [Syntax] = [Syntax(node)]
+
+    // If the node is an `MissingDeclSyntax` and the placeholder is an editor placeholder
+    // we should not add a diagnostic that it's missing.
+    if let missing = missingNodes.first?.as(MissingDeclSyntax.self),
+      missing.placeholder.isEditorPlaceholder,
+      !missing.placeholder.isMissing
+    {
+      missingNodes = []
+    }
+
     if let parentWithTokens = ancestorWithMoreTokens, let index {
       let siblings = parentWithTokens.children(viewMode: .all)
       let siblingsAfter = siblings[siblings.index(after: index)...]
@@ -403,6 +413,10 @@ extension ParseDiagnosticsGenerator {
       }
     }
 
+    if missingNodes.isEmpty {
+      return .visitChildren
+    }
+
     let changes = missingNodes.map { node in
       if let missing = node.asProtocol(MissingNodeSyntax.self) {
         // For missing nodes, only make the placeholder present. Don’t make any

Sources/SwiftParserDiagnostics/ParseDiagnosticsGenerator.swift

@@ -675,7 +675,7 @@ public class ParseDiagnosticsGenerator: SyntaxAnyVisitor {
     if shouldSkip(node) {
       return .skipChildren
     }
-    if node.statements.only?.item.is(EditorPlaceholderExprSyntax.self) == true {
+    if let item = node.statements.only?.item.as(DeclReferenceExprSyntax.self), item.baseName.isEditorPlaceholder {
       // Only emit a single diagnostic about the editor placeholder and none for the missing '{' and '}'.
       addDiagnostic(node, .editorPlaceholderInSourceFile, handledNodes: [node.id])
       return .skipChildren

Sources/SwiftParserDiagnostics/generated/SyntaxKindNameForDiagnostics.swift

@@ -139,10 +139,6 @@ extension SyntaxKind {
       return "@_documentation argument"
     case .dynamicReplacementAttributeArguments:
       return "@_dynamicReplacement argument"
-    case .editorPlaceholderDecl:
-      return "editor placeholder"
-    case .editorPlaceholderExpr:
-      return "editor placeholder"
     case .effectsAttributeArgumentList:
       return "@_effects arguments"
     case .enumCaseDecl:

Sources/SwiftRefactor/ExpandEditorPlaceholder.swift

@@ -135,8 +135,7 @@ public struct ExpandEditorPlaceholder: EditRefactoringProvider {
 /// Expansion on `closure1` and `normalArg` is the same as `ExpandEditorPlaceholder`.
 public struct ExpandEditorPlaceholders: EditRefactoringProvider {
   public static func textRefactor(syntax token: TokenSyntax, in context: Void) -> [SourceEdit] {
-    guard let placeholder = token.parent?.as(EditorPlaceholderExprSyntax.self),
-      let arg = placeholder.parent?.as(LabeledExprSyntax.self),
+    guard let arg = token.parent?.as(LabeledExprSyntax.self),
       let argList = arg.parent?.as(LabeledExprListSyntax.self),
       let call = argList.parent?.as(FunctionCallExprSyntax.self)
     else {
@@ -190,8 +189,8 @@ extension FunctionTypeSyntax {
       placeholder = ExpandEditorPlaceholder.wrapInTypePlaceholder(ret, type: ret)
     }
 
-    let statementPlaceholder = EditorPlaceholderExprSyntax(
-      placeholder: .identifier(placeholder)
+    let statementPlaceholder = DeclReferenceExprSyntax(
+      baseName: .identifier(placeholder)
     )
     let closureStatement = CodeBlockItemSyntax(
       item: .expr(ExprSyntax(statementPlaceholder))
@@ -234,8 +233,9 @@ extension FunctionCallExprSyntax {
     var includedArg = false
     var argsToExpand = 0
     for arg in arguments.reversed() {
-      guard let expr = arg.expression.as(EditorPlaceholderExprSyntax.self),
-        let data = EditorPlaceholderData(token: expr.placeholder),
+      guard let expr = arg.expression.as(DeclReferenceExprSyntax.self),
+        expr.baseName.isEditorPlaceholder,
+        let data = EditorPlaceholderData(token: expr.baseName),
         case let .typed(_, type) = data,
         type.is(FunctionTypeSyntax.self)
       else {
@@ -253,7 +253,7 @@ extension FunctionCallExprSyntax {
 
     var expandedArgs = [LabeledExprSyntax]()
     for arg in arguments.suffix(argsToExpand) {
-      let edits = ExpandEditorPlaceholder.textRefactor(syntax: arg.expression.cast(EditorPlaceholderExprSyntax.self).placeholder)
+      let edits = ExpandEditorPlaceholder.textRefactor(syntax: arg.expression.cast(DeclReferenceExprSyntax.self).baseName)
       guard edits.count == 1, let edit = edits.first, !edit.replacement.isEmpty else {
         return nil
       }

Sources/SwiftSyntax/Documentation.docc/generated/SwiftSyntax.md

@@ -70,7 +70,6 @@ These articles are intended for developers wishing to contribute to SwiftSyntax
 - <doc:SwiftSyntax/AssociatedTypeDeclSyntax>
 - <doc:SwiftSyntax/ClassDeclSyntax>
 - <doc:SwiftSyntax/DeinitializerDeclSyntax>
-- <doc:SwiftSyntax/EditorPlaceholderDeclSyntax>
 - <doc:SwiftSyntax/EnumCaseDeclSyntax>
 - <doc:SwiftSyntax/EnumDeclSyntax>
 - <doc:SwiftSyntax/ExtensionDeclSyntax>
@@ -110,7 +109,6 @@ These articles are intended for developers wishing to contribute to SwiftSyntax
 - <doc:SwiftSyntax/DeclReferenceExprSyntax>
 - <doc:SwiftSyntax/DictionaryExprSyntax>
 - <doc:SwiftSyntax/DiscardAssignmentExprSyntax>
-- <doc:SwiftSyntax/EditorPlaceholderExprSyntax>
 - <doc:SwiftSyntax/FloatLiteralExprSyntax>
 - <doc:SwiftSyntax/ForceUnwrapExprSyntax>
 - <doc:SwiftSyntax/FunctionCallExprSyntax>