[NFC] Refactor parseQualifiedTypeIdentifier()

Changes it to share code with `parseTypeIdentifier()` and clean up the member type parsing a little. Also tweaks call sites of `parseTypeIdentifier()`.

Author: beccadax

Sources/SwiftParser/Names.swift

@@ -188,36 +188,24 @@ extension Parser {
   }
 
   mutating func parseQualifiedTypeIdentifier() -> RawTypeSyntax {
-    if self.at(.keyword(.Any)) {
-      return RawTypeSyntax(self.parseAnyType())
-    }
 
-    let (unexpectedBeforeName, name) = self.expect(anyIn: IdentifierTypeSyntax.NameOptions.self, default: .identifier)
-    let generics: RawGenericArgumentClauseSyntax?
-    if self.at(prefix: "<") {
-      generics = self.parseGenericArguments()
-    } else {
-      generics = nil
+    let identifierType = self.parseTypeIdentifier()
+    var result = RawTypeSyntax(identifierType)
+
+    // There are no nested types inside `Any`.
+    if case TokenSpec.keyword(.Any) = identifierType.name {
+      return result
     }
 
-    var result = RawTypeSyntax(
-      RawIdentifierTypeSyntax(
-        moduleSelector: nil,
-        unexpectedBeforeName,
-        name: name,
-        genericArgumentClause: generics,
-        arena: self.arena
-      )
-    )
+    func hasAnotherMember() -> Bool {
+      // If qualified name base type cannot be parsed from the current
+      // point (i.e. the next type identifier is not followed by a '.'),
+      // then the next identifier is the final declaration name component.
+      var lookahead = self.lookahead()
+      return lookahead.consume(ifPrefix: ".", as: .period) != nil && lookahead.canParseBaseTypeForQualifiedDeclName()
+    }
 
-    // If qualified name base type cannot be parsed from the current
-    // point (i.e. the next type identifier is not followed by a '.'),
-    // then the next identifier is the final declaration name component.
-    var lookahead = self.lookahead()
-    guard
-      lookahead.consume(ifPrefix: ".", as: .period) != nil,
-      lookahead.canParseBaseTypeForQualifiedDeclName()
-    else {
+    guard hasAnotherMember() else {
       return result
     }
 
@@ -248,14 +236,7 @@ extension Parser {
         )
       )
 
-      // If qualified name base type cannot be parsed from the current
-      // point (i.e. the next type identifier is not followed by a '.'),
-      // then the next identifier is the final declaration name component.
-      var lookahead = self.lookahead()
-      guard
-        lookahead.consume(ifPrefix: ".", as: .period) != nil,
-        lookahead.canParseBaseTypeForQualifiedDeclName()
-      else {
+      guard hasAnotherMember() else {
         break
       }
 

Sources/SwiftParser/Types.swift

@@ -249,7 +249,7 @@ extension Parser {
     var base: RawTypeSyntax
     switch self.at(anyIn: TypeBaseStart.self)?.spec {
     case .Self, .Any, .identifier:
-      base = self.parseTypeIdentifier()
+      base = RawTypeSyntax(self.parseTypeIdentifier())
     case .leftParen:
       base = RawTypeSyntax(self.parseTupleTypeBody())
     case .leftSquare:
@@ -364,9 +364,9 @@ extension Parser {
   }
 
   /// Parse a type identifier.
-  mutating func parseTypeIdentifier() -> RawTypeSyntax {
+  mutating func parseTypeIdentifier() -> RawIdentifierTypeSyntax {
     if self.at(.keyword(.Any)) {
-      return RawTypeSyntax(self.parseAnyType())
+      return self.parseAnyType()
     }
 
     let (unexpectedBeforeName, name) = self.expect(anyIn: IdentifierTypeSyntax.NameOptions.self, default: .identifier)
@@ -377,14 +377,12 @@ extension Parser {
       generics = nil
     }
 
-    return RawTypeSyntax(
-      RawIdentifierTypeSyntax(
-        moduleSelector: nil,
-        unexpectedBeforeName,
-        name: name,
-        genericArgumentClause: generics,
-        arena: self.arena
-      )
+    return RawIdentifierTypeSyntax(
+      moduleSelector: nil,
+      unexpectedBeforeName,
+      name: name,
+      genericArgumentClause: generics,
+      arena: self.arena
     )
   }
 
@@ -1342,9 +1340,7 @@ extension Parser {
 
 extension Parser {
   mutating func parseResultType() -> RawTypeSyntax {
-    if self.currentToken.isEditorPlaceholder {
-      return self.parseTypeIdentifier()
-    } else if self.at(prefix: "<") {
+    if self.at(prefix: "<") && !self.currentToken.isEditorPlaceholder {
       let generics = self.parseGenericParameters()
       let baseType = self.parseType()
       return RawTypeSyntax(
@@ -1361,6 +1357,9 @@ extension Parser {
         return result
       }
 
+      // The rest of this tries to recover from a missing left square bracket like ` -> [Int]]? {`. We can do this for
+      // result types because we know there isn't an enclosing expression context.
+
       // If the right square bracket is at a new line, we should just return the result
       if let rightSquare = self.consume(if: TokenSpec(.rightSquare, allowAtStartOfLine: false)) {
         result = RawTypeSyntax(