[5.3][CodeCompletion] Avoid suggesting duplicated module names

lib/IDE/CodeCompletion.cpp

@@ -6196,6 +6196,8 @@ void CodeCompletionCallbacksImpl::doneParsing() {
     break;
   }
 
+  llvm::SmallPtrSet<Identifier, 8> seenModuleNames;
+
   for (auto &Request: Lookup.RequestedCachedResults) {
     // Use the current SourceFile as the DeclContext so that we can use it to
     // perform qualified lookup, and to get the correct visibility for
@@ -6248,7 +6250,9 @@ void CodeCompletionCallbacksImpl::doneParsing() {
           return; // already handled.
         RequestedModules.push_back({std::move(K), TheModule,
           Request.OnlyTypes, Request.OnlyPrecedenceGroups});
-        if (Request.IncludeModuleQualifier)
+
+        if (Request.IncludeModuleQualifier &&
+            seenModuleNames.insert(TheModule->getName()).second)
           Lookup.addModuleName(TheModule);
       }
     };
@@ -6263,8 +6267,10 @@ void CodeCompletionCallbacksImpl::doneParsing() {
       Lookup.getToplevelCompletions(Request.OnlyTypes);
 
       // Add the qualifying module name
-      if (Request.IncludeModuleQualifier)
-        Lookup.addModuleName(CurDeclContext->getParentModule());
+      auto curModule = CurDeclContext->getParentModule();
+      if (Request.IncludeModuleQualifier &&
+          seenModuleNames.insert(curModule->getName()).second)
+        Lookup.addModuleName(curModule);
 
       // Add results for all imported modules.
       ModuleDecl::ImportFilter ImportFilter;

test/IDE/Inputs/mock-sdk/OverlayTest.framework/Headers/OverlayTest.h

@@ -0,0 +1,2 @@
+#include <OverlayTest/Overlayed.h>
+

test/IDE/Inputs/mock-sdk/OverlayTest.framework/Headers/Overlayed.h

@@ -0,0 +1,13 @@
+
+#ifndef OVERLAYED_H
+#define OVERLAYED_H
+
+struct __attribute__((swift_name("Overlayed"))) OVOverlayed {
+  double x, y, z;
+};
+
+double OVOverlayedInOriginalFunc(struct OVOverlayed s) __attribute__((swift_name("Overlayed.inOriginalFunc(self:)")));
+
+struct OVOverlayed createOverlayed();
+
+#endif

test/IDE/Inputs/mock-sdk/OverlayTest.framework/Modules/module.modulemap

@@ -0,0 +1,7 @@
+framework module OverlayTest {
+  umbrella header "OverlayTest.h"
+
+  export *
+  module * { export * }
+}
+

test/IDE/Inputs/mock-sdk/OverlayTest.swiftinterface

@@ -0,0 +1,10 @@
+// swift-interface-format-version: 1.0
+// swift-module-flags: -module-name OverlayTest
+
+@_exported import OverlayTest
+
+public extension Overlayed {
+    public func inOverlayFunc() {}
+}
+
+public func createOverlayedInOverlay() -> Overlayed

test/IDE/complete_overlaymodule.swift

@@ -0,0 +1,37 @@
+// RUN: %target-swift-ide-test -code-completion -source-filename %s -I %S/Inputs/mock-sdk -F %S/Inputs/mock-sdk -code-completion-token=TYPE_GLOBAL | %FileCheck %s --check-prefix=TYPE_GLOBAL
+// RUN: %target-swift-ide-test -code-completion -source-filename %s -I %S/Inputs/mock-sdk -F %S/Inputs/mock-sdk -code-completion-token=EXPR_GLOBAL | %FileCheck %s --check-prefix=EXPR_GLOBAL
+// RUN: %target-swift-ide-test -code-completion -source-filename %s -I %S/Inputs/mock-sdk -F %S/Inputs/mock-sdk -code-completion-token=EXPR_MEMBER | %FileCheck %s --check-prefix=EXPR_MEMBER
+
+import OverlayTest
+
+func testGlobalType() {
+    let _: #^TYPE_GLOBAL^#
+// TYPE_GLOBAL: Begin completions
+// TYPE_GLOBAL-NOT: OverlayTest[#Module#]
+// TYPE_GLOBAL-DAG: Decl[Module]/None:                  OverlayTest[#Module#];
+// TYPE_GLOBAL-NOT: OverlayTest[#Module#]
+// TYPE_GLOBAL-DAG: Decl[Struct]/OtherModule[OverlayTest.Overlayed]: Overlayed[#Overlayed#];
+// TYPE_GLOBAL: End completions
+}
+func testGlobalExpr() {
+    let _ = #^EXPR_GLOBAL^#
+// EPXR_GLOBAL: Begin completions
+// EXPR_GLOBAL-NOT: OverlayTest[#Module#]
+// EXPR_GLOBAL-DAG: Decl[Module]/None:                  OverlayTest[#Module#];
+// EXPR_GLOBAL-NOT: OverlayTest[#Module#]
+// EXPR_GLOBAL-DAG: Decl[Struct]/OtherModule[OverlayTest.Overlayed]: Overlayed[#Overlayed#];
+// EXPR_GLOBAL-DAG: Decl[FreeFunction]/OtherModule[OverlayTest]: createOverlayedInOverlay()[#Overlayed#];
+// EXPR_GLOBAL-DAG: Decl[FreeFunction]/OtherModule[OverlayTest.Overlayed]: createOverlayed()[#Overlayed#];
+// EPXR_GLOBAL: End completions
+}
+func testGlobalExpr(value: Overlayed) {
+    value.#^EXPR_MEMBER^#
+// EXPR_MEMBER: Begin completions, 6 items
+// EXPR_MEMBER-DAG: Keyword[self]/CurrNominal:          self[#Overlayed#]; name=self
+// EXPR_MEMBER-DAG: Decl[InstanceVar]/CurrNominal:      x[#Double#]; name=x
+// EXPR_MEMBER-DAG: Decl[InstanceVar]/CurrNominal:      y[#Double#]; name=y
+// EXPR_MEMBER-DAG: Decl[InstanceVar]/CurrNominal:      z[#Double#]; name=z
+// EXPR_MEMBER-DAG: Decl[InstanceMethod]/CurrNominal:   inOverlayFunc()[#Void#]; name=inOverlayFunc()
+// EXPR_MEMBER-DAG: Decl[InstanceMethod]/CurrNominal:   inOriginalFunc()[#Double#]; name=inOriginalFunc()
+// EXPR_MEMBER: End completions
+}