[Sema] NFC: Clean up the entrypoint to ContextualizeClosuresAndMacros

Expose a generic `TypeChecker::contextualizeExpr`
to invoke it.

Author: hamishknight

lib/Sema/TypeCheckDeclPrimary.cpp

@@ -1337,7 +1337,7 @@ Expr *DefaultArgumentExprRequest::evaluate(Evaluator &evaluator,
 
   // Walk the checked initializer and contextualize any closures
   // we saw there.
-  TypeChecker::contextualizeInitializer(dc, initExpr);
+  TypeChecker::contextualizeExpr(initExpr, dc);
   TypeChecker::checkInitializerEffects(dc, initExpr);
 
   return initExpr;

lib/Sema/TypeCheckExpr.cpp

@@ -772,7 +772,7 @@ Expr *CallerSideDefaultArgExprRequest::evaluate(
     return new (ctx) ErrorExpr(initExpr->getSourceRange(), paramTy);
   }
   if (param->getDefaultArgumentKind() == DefaultArgumentKind::ExpressionMacro) {
-    TypeChecker::contextualizeCallSideDefaultArgument(dc, initExpr);
+    TypeChecker::contextualizeExpr(initExpr, dc);
     TypeChecker::checkCallerSideDefaultArgumentEffects(dc, initExpr);
   }
   return initExpr;

lib/Sema/TypeCheckStmt.cpp

@@ -66,9 +66,14 @@ namespace {
   /// DeclContext.
   class ContextualizeClosuresAndMacros : public ASTWalker {
     DeclContext *ParentDC;
-  public:
+
     ContextualizeClosuresAndMacros(DeclContext *parent) : ParentDC(parent) {}
 
+  public:
+    static void contextualize(ASTNode node, DeclContext *DC) {
+      node.walk(ContextualizeClosuresAndMacros(DC));
+    }
+
     MacroWalking getMacroWalkingBehavior() const override {
       return MacroWalking::ArgumentsAndExpansion;
     }
@@ -103,7 +108,7 @@ namespace {
 
       if (auto CE = dyn_cast<ClosureExpr>(E)) {
         CE->setParent(ParentDC);
-        CE->getBody()->walk(ContextualizeClosuresAndMacros(CE));
+        contextualize(CE->getBody(), CE);
 
         TypeChecker::computeCaptures(CE);
         return Action::SkipNode(E);
@@ -196,21 +201,13 @@ namespace {
   };
 } // end anonymous namespace
 
-void TypeChecker::contextualizeInitializer(Initializer *DC, Expr *E) {
-  ContextualizeClosuresAndMacros CC(DC);
-  E->walk(CC);
-}
-
-void TypeChecker::contextualizeCallSideDefaultArgument(DeclContext *DC,
-                                                       Expr *E) {
-  ContextualizeClosuresAndMacros CC(DC);
-  E->walk(CC);
+void TypeChecker::contextualizeExpr(Expr *E, DeclContext *DC) {
+  ContextualizeClosuresAndMacros::contextualize(E, DC);
 }
 
 void TypeChecker::contextualizeTopLevelCode(TopLevelCodeDecl *TLCD) {
-  ContextualizeClosuresAndMacros CC(TLCD);
   if (auto *body = TLCD->getBody())
-    body->walk(CC);
+    ContextualizeClosuresAndMacros::contextualize(body, TLCD);
 }
 
 namespace {
@@ -1033,7 +1030,7 @@ class StmtChecker : public StmtVisitor<StmtChecker, Stmt*> {
   /// Type-check an entire function body.
   bool typeCheckBody(BraceStmt *&S) {
     bool HadError = typeCheckStmt(S);
-    S->walk(ContextualizeClosuresAndMacros(DC));
+    ContextualizeClosuresAndMacros::contextualize(S, DC);
     return HadError;
   }
 
@@ -2915,7 +2912,7 @@ TypeCheckFunctionBodyRequest::evaluate(Evaluator &eval,
         body = *optBody;
         alreadyTypeChecked = true;
 
-        body->walk(ContextualizeClosuresAndMacros(AFD));
+        ContextualizeClosuresAndMacros::contextualize(body, AFD);
       }
     }
   }

lib/Sema/TypeCheckStorage.cpp

@@ -618,7 +618,7 @@ static void checkAndContextualizePatternBindingInit(PatternBindingDecl *binding,
 
   if (auto *initContext = binding->getInitContext(i)) {
     auto *init = binding->getInit(i);
-    TypeChecker::contextualizeInitializer(initContext, init);
+    TypeChecker::contextualizeExpr(init, initContext);
   }
 }
 
@@ -3200,7 +3200,7 @@ static void typeCheckSynthesizedWrapperInitializer(VarDecl *wrappedVar,
   // will be done in visitPatternBindingDecl.
   if (!contextualize)
     return;
-  TypeChecker::contextualizeInitializer(initContext, initializer);
+  TypeChecker::contextualizeExpr(initializer, initContext);
   checkPropertyWrapperActorIsolation(wrappedVar, initializer);
   TypeChecker::checkInitializerEffects(initContext, initializer);
 }

lib/Sema/TypeChecker.h

@@ -773,10 +773,9 @@ void computeCaptures(AbstractClosureExpr *ACE);
 /// Check for invalid captures from stored property initializers.
 void checkPatternBindingCaptures(IterableDeclContext *DC);
 
-/// Change the context of closures in the given initializer
-/// expression to the given context.
-void contextualizeInitializer(Initializer *DC, Expr *init);
-void contextualizeCallSideDefaultArgument(DeclContext *DC, Expr *init);
+/// Update the DeclContexts for AST nodes in a given DeclContext. This is
+/// necessary after type-checking since autoclosures may have been introduced.
+void contextualizeExpr(Expr *E, DeclContext *DC);
 void contextualizeTopLevelCode(TopLevelCodeDecl *TLCD);
 
 /// Retrieve the default type for the given protocol.