sourcekitd: define a new custom buffer for expression type response.

This custom buffer encapsulates the memory layout details of the response
for the expression type request. From the client side, each expression type
is represented as a tuple of {expr_offset, expr_length, printed_type}.

rdar://35199889

Author: nkcsgexi

lib/IDE/IDETypeChecking.cpp

@@ -638,11 +638,13 @@ class ExpressionTypeCollector: public SourceEntityWalker {
     {
       llvm::raw_svector_ostream OS(Buffer);
       E->getType()->getRValueType()->reconstituteSugar(true)->print(OS);
+      // Ensure the end user can directly use the char*
+      OS << '\0';
     }
 
     // Add the type information to the result list.
     Results.push_back({Offset, Length, getTypeOffsets(Buffer.str()),
-      static_cast<uint32_t>(Buffer.size())});
+      static_cast<uint32_t>(Buffer.size()) - 1});
 
     // Keep track of that we have a type reported for this range.
     AllPrintedTypes[Offset].insert(Length);

test/SourceKit/ExpressionType/basic.swift

@@ -1,4 +1,34 @@
-func foo() { return 1 }
+func foo() -> Int  { return 1 }
+
+func bar(f: Float) -> Float { return bar(f: 1) }
+
+protocol P {}
+
+func fooP(_ p: P) { fooP(p) }
+
+class C {}
+
+func ArrayC(_ a: [C]) {
+	_ = a.count
+	_ = a.description.count.advanced(by: 1).description
+}
+
+struct S {
+  let val = 4
+}
+func DictS(_ a: [Int: S]) {
+  _ = a[2]?.val.advanced(by: 1).byteSwapped
+}
 
 // RUN: %sourcekitd-test -req=collect-type %s -- %s | %FileCheck %s
-// CHECK: (20, 21): Int
+// CHECK: (183, 202): Int
+// CHECK: (183, 196): String
+// CHECK: (183, 184): [C]
+// CHECK: (203, 211): (Int) -> (Int) -> Int
+// CHECK: (211, 218): (by: Int)
+// CHECK: (216, 217): Int
+// CHECK: (257, 258): Int
+// CHECK: (291, 332): ()
+// CHECK: (291, 292): Int?
+// CHECK: (295, 332): Int?
+// CHECK: (295, 320): Int

tools/SourceKit/include/SourceKit/Core/LangSupport.h

@@ -128,7 +128,6 @@ struct ExpressionType {
   unsigned ExprOffset;
   unsigned ExprLength;
   unsigned TypeOffset;
-  unsigned TypeLength;
 };
 
 struct ExpressionTypesInFile {

tools/SourceKit/lib/SwiftLang/SwiftSourceDocInfo.cpp

@@ -2057,8 +2057,7 @@ void SwiftLangSupport::collectExpressionTypes(StringRef FileName,
       llvm::raw_svector_ostream OS(TypeBuffer);
       ExpressionTypesInFile Result;
       for (auto Item: collectExpressionType(*SF, Scratch, OS)) {
-        Result.Results.push_back({Item.offset, Item.length, Item.typeOffset,
-          Item.typeLength});
+        Result.Results.push_back({Item.offset, Item.length, Item.typeOffset});
       }
       Result.TypeBuffer = OS.str();
       Receiver(Result);

tools/SourceKit/tools/sourcekitd-test/sourcekitd-test.cpp

@@ -1537,20 +1537,18 @@ static void printRangeInfo(sourcekitd_variant_t Info, StringRef FilenameIn,
 }
 
 static void printExpressionType(sourcekitd_variant_t Info, llvm::raw_ostream &OS) {
-  auto *TypeBuffer = sourcekitd_variant_dictionary_get_string(Info, KeyTypeBuffer);
-  sourcekitd_variant_t ExprList = sourcekitd_variant_dictionary_get_value(Info,
-    KeyExpressionTypeList);
-  unsigned Count = sourcekitd_variant_array_get_count(ExprList);
+  auto TypeBuffer = sourcekitd_variant_dictionary_get_value(Info, KeyExpressionTypeList);
+  unsigned Count = sourcekitd_variant_array_get_count(TypeBuffer);
+  if (!Count) {
+    OS << "cannot find expression types in the file\n";
+    return;
+  }
   for (unsigned i = 0; i != Count; ++i) {
-    sourcekitd_variant_t Item = sourcekitd_variant_array_get_value(ExprList, i);
+    sourcekitd_variant_t Item = sourcekitd_variant_array_get_value(TypeBuffer, i);
     unsigned Offset = sourcekitd_variant_dictionary_get_int64(Item, KeyExpressionOffset);
     unsigned Length = sourcekitd_variant_dictionary_get_int64(Item, KeyExpressionLength);
-    StringRef PrintedType(TypeBuffer + sourcekitd_variant_dictionary_get_int64(Item,
-      KeyTypeOffset), sourcekitd_variant_dictionary_get_int64(Item, KeyTypeLength));
-    OS << "(" << Offset << ", " << Offset + Length << "): " << PrintedType << "\n";
-  }
-  if (!Count) {
-    OS << "cannot find expression types in the file\n";
+    OS << "(" << Offset << ", " << Offset + Length << "): " <<
+      sourcekitd_variant_dictionary_get_string(Item, KeyExpressionType) << "\n";
   }
 }
 

tools/SourceKit/tools/sourcekitd/include/sourcekitd/CompactArray.h

@@ -22,7 +22,7 @@ class CompactArrayBuilderImpl {
 public:
   std::unique_ptr<llvm::MemoryBuffer> createBuffer() const;
   void appendTo(llvm::SmallVectorImpl<char> &Buf) const;
-
+  unsigned copyInto(char *BufPtr) const;
   size_t sizeInBytes() const;
   bool empty() const;
 

tools/SourceKit/tools/sourcekitd/include/sourcekitd/ExpressionTypeArray.h

@@ -0,0 +1,41 @@
+//===--- ExpressionTypeArray.h - --------------------------------*- C++ -*-===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_SOURCEKITD_EXPRESSION_TYPE_ARRAY_H
+#define LLVM_SOURCEKITD_EXPRESSION_TYPE_ARRAY_H
+
+#include "sourcekitd/Internal.h"
+
+namespace SourceKit {
+  struct ExpressionType;
+}
+
+namespace sourcekitd {
+VariantFunctions *getVariantFunctionsForExpressionTypeArray();
+
+class ExpressionTypeArrayBuilder {
+public:
+  ExpressionTypeArrayBuilder(llvm::StringRef PrintedType);
+  ~ExpressionTypeArrayBuilder();
+
+  void add(const SourceKit::ExpressionType &ExpType);
+  std::unique_ptr<llvm::MemoryBuffer> createBuffer();
+  static VariantFunctions Funcs;
+
+private:
+  struct Implementation;
+  Implementation &Impl;
+};
+
+}
+
+#endif

tools/SourceKit/tools/sourcekitd/include/sourcekitd/Internal.h

@@ -59,6 +59,7 @@ enum class CustomBufferKind {
   InheritedTypesArray,
   DocStructureElementArray,
   AttributesArray,
+  ExpressionTypeArray,
   RawData
 };
 

tools/SourceKit/tools/sourcekitd/lib/API/CMakeLists.txt

@@ -8,6 +8,7 @@ set(sourcekitdAPI_sources
   Requests.cpp
   sourcekitdAPI-Common.cpp
   TokenAnnotationsArray.cpp
+  ExpressionTypeArray.cpp
 )
 
 set(sourcekitdAPI_Darwin_sources

tools/SourceKit/tools/sourcekitd/lib/API/CompactArray.cpp

@@ -94,6 +94,12 @@ void CompactArrayBuilderImpl::copyInto(char *BufPtr, size_t Length) const {
   memcpy(BufPtr, StringBuffer.data(), StringBuffer.size());
 }
 
+unsigned CompactArrayBuilderImpl::copyInto(char *BufPtr) const {
+  size_t Length = sizeInBytes();
+  copyInto(BufPtr, Length);
+  return Length;
+}
+
 bool CompactArrayBuilderImpl::empty() const {
   return EntriesBuffer.empty();
 }