[Parse] Consolidate AFD body parsing implemtations

Author: rintaro

include/swift/Parse/Parser.h

@@ -1122,6 +1122,8 @@ class Parser {
                                        ParseDeclOptions Flags,
                                        DeclAttributes &Attributes,
                                        bool HasFuncKeyword = true);
+  ParserResult<BraceStmt>
+  parseAbstractFunctionBodyImpl(AbstractFunctionDecl *AFD);
   void parseAbstractFunctionBody(AbstractFunctionDecl *AFD);
   BraceStmt *parseAbstractFunctionBodyDelayed(AbstractFunctionDecl *AFD);
   ParserResult<ProtocolDecl> parseDeclProtocol(ParseDeclOptions Flags,

lib/Parse/ParseDecl.cpp

@@ -6328,7 +6328,30 @@ ParserResult<FuncDecl> Parser::parseDeclFunc(SourceLoc StaticLoc,
   return DCC.fixupParserResult(FD);
 }
 
-/// Parse function body into \p AFD.
+/// Parse a function body for \p AFD and returns it without setting the body
+/// to \p AFD .
+ParserResult<BraceStmt>
+Parser::parseAbstractFunctionBodyImpl(AbstractFunctionDecl *AFD) {
+  assert(Tok.is(tok::l_brace));
+
+  // Enter the arguments for the function into a new function-body scope.  We
+  // need this even if there is no function body to detect argument name
+  // duplication.
+  if (auto *P = AFD->getImplicitSelfDecl())
+    addToScope(P);
+  addParametersToScope(AFD->getParameters());
+
+   // Establish the new context.
+  ParseFunctionBody CC(*this, AFD);
+  setLocalDiscriminatorToParamList(AFD->getParameters());
+
+  if (Context.Stats)
+    Context.Stats->getFrontendCounters().NumFunctionsParsed++;
+
+  return parseBraceItemList(diag::invalid_diagnostic);
+}
+
+/// Parse function body into \p AFD or skip it for delayed parsing.
 void Parser::parseAbstractFunctionBody(AbstractFunctionDecl *AFD) {
   if (!Tok.is(tok::l_brace)) {
     checkForInputIncomplete();
@@ -6348,21 +6371,7 @@ void Parser::parseAbstractFunctionBody(AbstractFunctionDecl *AFD) {
 
   Scope S(this, ScopeKind::FunctionBody);
 
-  // Enter the arguments for the function into a new function-body scope.  We
-  // need this even if there is no function body to detect argument name
-  // duplication.
-  if (auto *P = AFD->getImplicitSelfDecl())
-    addToScope(P);
-  addParametersToScope(AFD->getParameters());
-
-   // Establish the new context.
-  ParseFunctionBody CC(*this, AFD);
-  setLocalDiscriminatorToParamList(AFD->getParameters());
-
-  if (Context.Stats)
-    Context.Stats->getFrontendCounters().NumFunctionsParsed++;
-
-  ParserResult<BraceStmt> Body = parseBraceItemList(diag::invalid_diagnostic);
+  ParserResult<BraceStmt> Body = parseAbstractFunctionBodyImpl(AFD);
   if (!Body.isNull()) {
     BraceStmt * BS = Body.get();
     AFD->setBodyParsed(BS);
@@ -6445,13 +6454,8 @@ BraceStmt *Parser::parseAbstractFunctionBodyDelayed(AbstractFunctionDecl *AFD) {
   // Re-enter the lexical scope.
   Scope TopLevelScope(this, ScopeKind::TopLevel);
   Scope S(this, ScopeKind::FunctionBody);
-  if (auto *P = AFD->getImplicitSelfDecl())
-    addToScope(P);
-  addParametersToScope(AFD->getParameters());
-  ParseFunctionBody CC(*this, AFD);
-  setLocalDiscriminatorToParamList(AFD->getParameters());
 
-  return parseBraceItemList(diag::func_decl_without_brace).getPtrOrNull();
+  return parseAbstractFunctionBodyImpl(AFD).getPtrOrNull();
 }
 
 /// Parse a 'enum' declaration, returning true (and doing no token

lib/Parse/Parser.cpp

@@ -197,16 +197,7 @@ void Parser::performCodeCompletionSecondPassImpl(
 
   case CodeCompletionDelayedDeclKind::FunctionBody: {
     auto *AFD = cast<AbstractFunctionDecl>(DC);
-
-    if (auto *P = AFD->getImplicitSelfDecl())
-      addToScope(P);
-    addParametersToScope(AFD->getParameters());
-
-    ParseFunctionBody CC(*this, AFD);
-    setLocalDiscriminatorToParamList(AFD->getParameters());
-
-    auto result = parseBraceItemList(diag::func_decl_without_brace);
-    AFD->setBody(result.getPtrOrNull());
+    AFD->setBodyParsed(parseAbstractFunctionBodyImpl(AFD).getPtrOrNull());
     break;
   }
   }