Merge pull request swiftlang#26723 from nathawes/r54047322-fix-completion-crash-in-addFunctionCallPattern

[IDE] Fix code completion crash after already-typechecked ApplyExpr

Author: Nathan Hawes

lib/IDE/CodeCompletion.cpp

@@ -1279,11 +1279,23 @@ class CodeCompletionCallbacksImpl : public CodeCompletionCallbacks {
     if (CheckKind == CompletionTypeCheckKind::Normal &&
         ParsedExpr->getType() && !ParsedExpr->getType()->is<ErrorType>()) {
       auto refDecl = ParsedExpr->getReferencedDecl();
+      auto exprTy = ParsedExpr->getType();
       if (!refDecl) {
-        if (auto apply = dyn_cast<ApplyExpr>(ParsedExpr))
+        // FIXME: do this in the not-already-type-checked branch too?
+        if (auto *apply = dyn_cast<SelfApplyExpr>(ParsedExpr)) {
           refDecl = apply->getFn()->getReferencedDecl();
+        } else if (auto *apply = dyn_cast<ApplyExpr>(ParsedExpr)) {
+          // If this is an IUO, use the underlying non-optional type instead
+          auto fnDecl = apply->getFn()->getReferencedDecl();
+          if (auto FD = fnDecl.getDecl()) {
+            if (FD->isImplicitlyUnwrappedOptional()) {
+              if (auto OT = exprTy->getOptionalObjectType())
+                exprTy = OT;
+            }
+          }
+        }
       }
-      return std::make_pair(ParsedExpr->getType(), refDecl);
+      return std::make_pair(exprTy, refDecl);
     }
 
     ConcreteDeclRef ReferencedDecl = nullptr;

test/IDE/complete_value_expr.swift

@@ -199,6 +199,7 @@
 // RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=IN_ARRAY_LITERAL_2 | %FileCheck %s -check-prefix=SIMPLE_OBJECT_DOT
 // RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=IN_DICTIONARY_LITERAL_1 | %FileCheck %s -check-prefix=SIMPLE_OBJECT_DOT
 // RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=IN_DICTIONARY_LITERAL_2 | %FileCheck %s -check-prefix=SIMPLE_OBJECT_DOT
+// RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=COMPLETE_CALL_RESULT | %FileCheck %s -check-prefix=COMPLETE_CALL_RESULT
 
 // Test code completion of expressions that produce a value.
 
@@ -2173,3 +2174,17 @@ func testInCollectionLiteral(value: SimpleStruct) {
     value.#^IN_DICTIONARY_LITERAL_2^# : "test"
   ]
 }
+
+// rdar://problem/54047322
+struct Resolver<T> {
+  func fulfill(_ value: T) {}
+}
+func wrapSuccess<T>(_ onSuccess: @escaping (T) -> Void) -> (T, Bool) -> Void {
+  fatalError()
+}
+func testWrapSuccess(promise: Int, seal: Resolver<Void>) {
+  wrapSuccess(seal.fulfill)#^COMPLETE_CALL_RESULT^#
+  // COMPLETE_CALL_RESULT: Begin completions
+  // COMPLETE_CALL_RESULT: Pattern/CurrModule:                 ({#Void#}, {#Bool#})[#Void#]; name=(Void, Bool)
+  // COMPLETE_CALL_RESULT: End completions
+}