[Parse][IDE] Don't drop default argument init exprs containing code completion exprs and type check them for code completion.

Fixes up some tests marked as non-ideal to give the ideal result now too.

Author: Nathan Hawes

lib/IDE/ExprContextAnalysis.cpp

@@ -85,6 +85,11 @@ void swift::ide::typeCheckContextAt(DeclContext *DC, SourceLoc Loc) {
             typeCheckPatternBinding(PBD, i);
         }
       }
+    } else if (auto *defaultArg = dyn_cast<DefaultArgumentInitializer>(DC)) {
+      if (auto *AFD = dyn_cast<AbstractFunctionDecl>(defaultArg->getParent())) {
+        auto *Param = AFD->getParameters()->get(defaultArg->getIndex());
+        (void*)Param->getTypeCheckedDefaultExpr();
+      }
     }
     break;
 

lib/Parse/ParsePattern.cpp

@@ -130,8 +130,10 @@ static ParserStatus parseDefaultArgument(
 
   defaultArgs->HasDefaultArgument = true;
 
-  if (initR.hasCodeCompletion())
+  if (initR.hasCodeCompletion()) {
+    init = initR.get();
     return makeParserCodeCompletionStatus();
+  }
 
   if (initR.isNull())
     return makeParserError();

test/IDE/complete_unresolved_members.swift

@@ -109,9 +109,9 @@
 // RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=GENERICPARAM_21 | %FileCheck %s -check-prefix=GENERICPARAM_1
 
 // RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=DECL_MEMBER_INIT_1 | %FileCheck %s -check-prefix=UNRESOLVED_3
-// RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=DEFAULT_ARG_1 | %FileCheck %s -check-prefix=UNRESOLVED_3_NOTIDEAL
-// RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=DEFAULT_ARG_2 | %FileCheck %s -check-prefix=UNRESOLVED_3_NOTIDEAL
-// RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=DEFAULT_ARG_3 | %FileCheck %s -check-prefix=UNRESOLVED_3_NOTIDEAL
+// RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=DEFAULT_ARG_1 | %FileCheck %s -check-prefix=UNRESOLVED_3
+// RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=DEFAULT_ARG_2 | %FileCheck %s -check-prefix=UNRESOLVED_3
+// RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=DEFAULT_ARG_3 | %FileCheck %s -check-prefix=UNRESOLVED_3
 
 // RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=TYPEPARAM_IN_CONTEXTTYPE_1 | %FileCheck %s -check-prefix=TYPEPARAM_IN_CONTEXTTYPE_1