Add module aliasing option to swift-ide-test

Add module aliasing handling in code complete
Resolves rdar://86294338

Author: elsh

include/swift/Frontend/Frontend.h

@@ -309,6 +309,8 @@ class CompilerInvocation {
     return FrontendOpts.ModuleName;
   }
 
+  void setModuleAliasMap(std::vector<std::string> args);
+
   std::string getOutputFilename() const {
     return FrontendOpts.InputsAndOutputs.getSingleOutputFilename();
   }

lib/Frontend/ArgsToFrontendOptionsConverter.cpp

@@ -516,6 +516,10 @@ bool ArgsToFrontendOptionsConverter::setUpImmediateArgs() {
 bool ArgsToFrontendOptionsConverter::computeModuleAliases() {
   auto list = Args.getAllArgValues(options::OPT_module_alias);
   if (!list.empty()) {
+    // ModuleAliasMap should initially be empty as setting
+    // it should be called only once
+    Opts.ModuleAliasMap.clear();
+
     auto validate = [this](StringRef value, bool allowModuleName) -> bool
     {
       if (!allowModuleName) {

lib/Frontend/CompilerInvocation.cpp

@@ -262,6 +262,33 @@ void CompilerInvocation::setSDKPath(const std::string &Path) {
   updateRuntimeLibraryPaths(SearchPathOpts, LangOpts.Target);
 }
 
+// This assumes the param args contains valid strings for module
+// aliasing. The full validation of input for aliasing is done at
+// ArgsToFrontendOptionsConverter::computeModulealiases.
+void CompilerInvocation::setModuleAliasMap(std::vector<std::string> args) {
+  // ModuleAliasMap should initially be empty as setting
+  // it should be called only once
+  FrontendOpts.ModuleAliasMap.clear();
+  for (auto item: args) {
+    auto str = StringRef(item);
+    // splits to an alias and the underlying name
+    auto pair = str.split('=');
+    auto lhs = pair.first;
+    auto rhs = pair.second;
+    if (rhs.empty()) // bad format, so skip to the next
+        continue;
+    if (!FrontendOpts.ModuleAliasMap.insert({rhs, StringRef()}).second) {
+      // the underlying name was already added, so skip
+      continue;
+    }
+    auto underlyingName = FrontendOpts.ModuleAliasMap.find(rhs)->first();
+    if (!FrontendOpts.ModuleAliasMap.insert({lhs, underlyingName}).second) {
+      // the alias was already added, so skip
+      continue;
+    }
+  }
+}
+
 static bool ParseFrontendArgs(
     FrontendOptions &opts, ArgList &args, DiagnosticEngine &diags,
     SmallVectorImpl<std::unique_ptr<llvm::MemoryBuffer>> *buffers) {

lib/IDE/CodeCompletion.cpp

@@ -2204,7 +2204,18 @@ class CompletionLookup final : public swift::VisibleDeclConsumer {
         SemanticContextKind::None,
         expectedTypeContext);
     Builder.setAssociatedDecl(MD);
-    Builder.addBaseName(MD->getNameStr());
+    auto moduleName = MD->getName();
+ 
+    // This checks if module aliasing was used. For example, when editing
+    // `import ...`, and `-module-alias Foo=Bar` was passed, we want to show
+    // Foo as an option to import, instead of Bar (name of the binary), as
+    // Foo is the name that should appear in source files.
+    auto aliasedName = Ctx.getRealModuleName(moduleName, ASTContext::ModuleAliasLookupOption::aliasFromRealName);
+    if (aliasedName != moduleName && // check if module aliasing was applied
+        !aliasedName.empty()) { // check an alias mapped to the binary name exists
+      moduleName = aliasedName; // if so, use the aliased name
+    }
+    Builder.addBaseName(moduleName.str());
     Builder.addTypeAnnotation("Module");
     if (R)
       Builder.setNotRecommended(*R);

test/IDE/module-aliasing-code-complete.swift

@@ -0,0 +1,128 @@
+/// Test code completion with module aliasing
+/// When -module-alias <alias_name>=<real_name> is applied, code completion should show
+/// the <alias_name> as that's the name which should appear in source files including import statements,
+/// decls, expressions, etc. while getting visible decls come from the module of <real_name>.
+/// Below, XLogging is the alias and mapped to the real name AppleLogging. Note that the real name
+/// AppleLogging should not appear in the code completion results.
+///
+// RUN: %empty-directory(%t)
+// RUN: %{python} %utils/split_file.py -o %t %s
+
+// RUN: %target-swift-frontend %t/FileLogging.swift -module-name AppleLogging -module-alias XLogging=AppleLogging -emit-module -o %t/AppleLogging.swiftmodule
+
+// RUN: %target-swift-ide-test -code-completion -code-completion-token=MODULE_NAME -source-filename %t/FileLib1.swift -module-alias XLogging=AppleLogging -I %t > %t/result1.txt
+// RUN: %FileCheck %s -check-prefix CHECK1 < %t/result1.txt
+
+// CHECK1-NOT: AppleLogging
+// CHECK1: found code completion token MODULE_NAME at offset 43
+// CHECK1: Begin completions, 335 items
+// CHECK1: Decl[Module]/None:                  XLogging[#Module#]; name=XLogging
+// CHECK1: Decl[Protocol]/OtherModule[XLogging]: Logging[#Logging#]; name=Logging
+// CHECK1: Decl[Struct]/OtherModule[XLogging]: Logger[#Logger#]; name=Logger
+// CHECK1: End completions
+
+
+// RUN: %target-swift-ide-test -code-completion -code-completion-token=MODULE_NAME -source-filename %t/FileLib2.swift -module-alias XLogging=AppleLogging -I %t > %t/result2.txt
+// RUN: %FileCheck %s -check-prefix CHECK2 < %t/result2.txt
+
+// CHECK2-NOT: AppleLogging
+// CHECK2: found code completion token MODULE_NAME at offset 48
+// CHECK2: Begin completions, 335 items
+// CHECK2: Decl[Module]/None:                  XLogging[#Module#]; name=XLogging
+// CHECK2: Decl[Protocol]/OtherModule[XLogging]: Logging[#Logging#]; name=Logging
+// CHECK2: Decl[Struct]/OtherModule[XLogging]: Logger[#Logger#]; name=Logger
+// CHECK2: End completions
+
+
+// RUN: %target-swift-ide-test -code-completion -code-completion-token=MODULE_NAME -source-filename %t/FileLib3.swift -module-alias XLogging=AppleLogging -I %t > %t/result3.txt
+// RUN: %FileCheck %s -check-prefix CHECK3 < %t/result3.txt
+
+// CHECK3-NOT: AppleLogging
+// CHECK3: found code completion token MODULE_NAME at offset 49
+// CHECK3: Begin completions, 516 items
+// CHECK3: Decl[Module]/None:                  XLogging[#Module#]; name=XLogging
+// CHECK3: Decl[Protocol]/OtherModule[XLogging]/Flair[RareType]: Logging[#Logging#]; name=Logging
+// CHECK3: Decl[Struct]/OtherModule[XLogging]: Logger[#Logger#]; name=Logger
+// CHECK3: Decl[FreeFunction]/OtherModule[XLogging]: setupLogger()[#Logger?#]; name=setupLogger()
+// CHECK3: End completions
+
+
+// RUN: %target-swift-ide-test -code-completion -code-completion-token=MODULE_NAME -source-filename %t/FileLib4.swift -module-alias XLogging=AppleLogging -I %t > %t/result4.txt
+// RUN: %FileCheck %s -check-prefix CHECK4 < %t/result4.txt
+
+// CHECK4-NOT: AppleLogging
+// CHECK4: found code completion token MODULE_NAME at offset 58
+// CHECK4: Begin completions, 3 items
+// CHECK4: Decl[Protocol]/OtherModule[XLogging]/Flair[RareType]: Logging[#Logging#]; name=Logging
+// CHECK4: Decl[Struct]/OtherModule[XLogging]: Logger[#Logger#]; name=Logger
+// CHECK4: Decl[FreeFunction]/OtherModule[XLogging]: setupLogger()[#Logger?#]; name=setupLogger()
+// CHECK4: End completions
+
+/// In the following, the module alias name should be shown as a module that can be imported instead of the real name
+///
+// RUN: %target-swift-ide-test -code-completion -code-completion-token=MODULE_NAME -source-filename %t/FileLib5.swift -module-alias XLogging=AppleLogging -I %t > %t/result5.txt
+// RUN: %FileCheck %s -check-prefix CHECK5 < %t/result5.txt
+
+/// In search paths, only AppleLogging.swiftmodule exists, but when `-module-alias XLogging=AppleLogging` is passed,
+/// we want to only show XLogging as an option to import, not AppleLogging
+// CHECK5-NOT: AppleLogging
+// CHECK5: found code completion token MODULE_NAME at offset 7
+// CHECK5: Begin completions, 233 items
+// CHECK5: Decl[Module]/None:                  XLogging[#Module#]; name=XLogging
+// CHECK5: End completions
+
+
+// RUN: %target-swift-ide-test -code-completion -code-completion-token=MODULE_NAME -source-filename %t/FileLib5.swift -I %t > %t/result6.txt
+// RUN: %FileCheck %s -check-prefix CHECK6 < %t/result6.txt
+
+/// In search paths, only AppleLogging.swiftmodule exists, and no module aliasing option is passed, so
+/// just show AppleLogging as one of the modules that can be imported
+// CHECK6-NOT: XLogging
+// CHECK6: found code completion token MODULE_NAME at offset 7
+// CHECK6: Begin completions, 233 items
+// CHECK6: Decl[Module]/None:                  AppleLogging[#Module#]; name=AppleLogging
+// CHECK6: End completions
+
+
+// BEGIN FileLogging.swift
+public struct Logger {
+  public init() {}
+}
+
+public protocol Logging {
+  var content: String { get }
+}
+
+public func setupLogger() -> XLogging.Logger? {
+  return Logger()
+}
+
+// BEGIN FileLib1.swift
+import XLogging
+
+class ModuleNameInClause: #^MODULE_NAME^# {
+}
+
+// BEGIN FileLib2.swift
+import XLogging
+
+func testModuleNameInDecl() -> #^MODULE_NAME^# {
+}
+
+// BEGIN FileLib3.swift
+import XLogging
+
+func testModuleNameInBody() {
+  #^MODULE_NAME^#
+}
+
+// BEGIN FileLib4.swift
+import XLogging
+
+func testModuleNameInBody() {
+  XLogging.#^MODULE_NAME^#
+}
+
+// BEGIN FileLib5.swift
+import #^MODULE_NAME^#
+

tools/swift-ide-test/swift-ide-test.cpp

@@ -338,6 +338,10 @@ EnableCrossImportOverlays("enable-cross-import-overlays",
                           llvm::cl::desc("Automatically import declared cross-import overlays."),
                           llvm::cl::cat(Category),
                           llvm::cl::init(false));
+static llvm::cl::list<std::string>
+ModuleAliases("module-alias",
+            llvm::cl::desc("Use '-module-alias <name>=<underlying_name>' to map a module of <name> to a different name"),
+            llvm::cl::cat(Category));
 
 static llvm::cl::opt<bool>
 SkipDeinit("skip-deinit",
@@ -4233,6 +4237,10 @@ int main(int argc, char *argv[]) {
     InitInvok.getLangOptions().AllowModuleWithCompilerErrors = true;
   }
 
+  if (!options::ModuleAliases.empty()) {
+    InitInvok.setModuleAliasMap(options::ModuleAliases);
+  }
+
   // Process the clang arguments last and allow them to override previously
   // set options.
   if (!CCArgs.empty()) {