From: Kadir Cetinkaya <kadircet@google.com>
Date: Fri, 24 Feb 2023 00:05:15 +0000 (+0100)
Subject: Revert "Revert "[Tooling/Inclusion] Handle std::get symbol.""
X-Git-Tag: upstream/17.0.6~16609
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=5a623c2a082d007c1cc7a878b666b3581bb8f8dc;p=platform%2Fupstream%2Fllvm.git

Revert "Revert "[Tooling/Inclusion] Handle std::get symbol.""

This reverts commit 7c9b15fbaeb2846ad25e797d55ffe1ccef9e1379. Breakage
was in downstream code.
---

diff --git a/clang-tools-extra/clangd/index/CanonicalIncludes.cpp b/clang-tools-extra/clangd/index/CanonicalIncludes.cpp
index 0c61a7b..4311eb9 100644
--- a/clang-tools-extra/clangd/index/CanonicalIncludes.cpp
+++ b/clang-tools-extra/clangd/index/CanonicalIncludes.cpp
@@ -717,7 +717,8 @@ llvm::StringRef CanonicalIncludes::mapSymbol(llvm::StringRef Scope,
   if (Scope == "std::" && Name == "move")
     return "<utility>";
   if (auto StdSym = tooling::stdlib::Symbol::named(Scope, Name, Lang))
-    return StdSym->header().name();
+    if (auto Header = StdSym->header())
+      return Header->name();
   return "";
 }
 
diff --git a/clang/include/clang/Tooling/Inclusions/StandardLibrary.h b/clang/include/clang/Tooling/Inclusions/StandardLibrary.h
index 9d45d84..a39ceb5 100644
--- a/clang/include/clang/Tooling/Inclusions/StandardLibrary.h
+++ b/clang/include/clang/Tooling/Inclusions/StandardLibrary.h
@@ -81,7 +81,7 @@ public:
   llvm::StringRef name() const;
   llvm::StringRef qualifiedName() const;
   // The preferred header for this symbol (e.g. the suggested insertion).
-  Header header() const;
+  std::optional<Header> header() const;
   // Some symbols may be provided by multiple headers.
   llvm::SmallVector<Header> headers() const;
 
diff --git a/clang/lib/Tooling/Inclusions/Stdlib/StandardLibrary.cpp b/clang/lib/Tooling/Inclusions/Stdlib/StandardLibrary.cpp
index 416b531..cfcb955 100644
--- a/clang/lib/Tooling/Inclusions/Stdlib/StandardLibrary.cpp
+++ b/clang/lib/Tooling/Inclusions/Stdlib/StandardLibrary.cpp
@@ -14,6 +14,7 @@
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/Casting.h"
+#include <optional>
 
 namespace clang {
 namespace tooling {
@@ -120,7 +121,8 @@ static int initialize(Lang Language) {
     }
     Mapping->SymbolNames[SymIndex] = {
         QName.data(), NSLen, static_cast<unsigned int>(QName.size() - NSLen)};
-    Mapping->SymbolHeaderIDs[SymIndex].push_back(AddHeader(HeaderName));
+    if (!HeaderName.empty())
+       Mapping->SymbolHeaderIDs[SymIndex].push_back(AddHeader(HeaderName));
 
     NSSymbolMap &NSSymbols = AddNS(QName.take_front(NSLen));
     NSSymbols.try_emplace(QName.drop_front(NSLen), SymIndex);
@@ -205,8 +207,11 @@ std::optional<Symbol> Symbol::named(llvm::StringRef Scope, llvm::StringRef Name,
   }
   return std::nullopt;
 }
-Header Symbol::header() const {
-  return Header(getMappingPerLang(Language)->SymbolHeaderIDs[ID][0], Language);
+std::optional<Header> Symbol::header() const {
+  const auto& Headers = getMappingPerLang(Language)->SymbolHeaderIDs[ID];
+  if (Headers.empty())
+    return std::nullopt;
+  return Header(Headers.front(), Language);
 }
 llvm::SmallVector<Header> Symbol::headers() const {
   llvm::SmallVector<Header> Results;
diff --git a/clang/lib/Tooling/Inclusions/Stdlib/StdSpecialSymbolMap.inc b/clang/lib/Tooling/Inclusions/Stdlib/StdSpecialSymbolMap.inc
index 3d2ea91..c9632be 100644
--- a/clang/lib/Tooling/Inclusions/Stdlib/StdSpecialSymbolMap.inc
+++ b/clang/lib/Tooling/Inclusions/Stdlib/StdSpecialSymbolMap.inc
@@ -218,3 +218,8 @@ SYMBOL(ssize, std::, <string_view>)
 SYMBOL(ssize, std::, <unordered_map>)
 SYMBOL(ssize, std::, <unordered_set>)
 SYMBOL(ssize, std::, <vector>)
+
+// std::get has a few variants for different types (tuple, array, pair etc)
+// which is tricky to disambiguate without type information.
+// Don't set any header for it, as it comes with the type header.
+SYMBOL(get, std::, /*no headers*/)
diff --git a/clang/unittests/Tooling/StandardLibraryTest.cpp b/clang/unittests/Tooling/StandardLibraryTest.cpp
index 47d064b..6d90bbd 100644
--- a/clang/unittests/Tooling/StandardLibraryTest.cpp
+++ b/clang/unittests/Tooling/StandardLibraryTest.cpp
@@ -58,6 +58,9 @@ TEST(StdlibTest, All) {
   EXPECT_EQ(Vector->header(), *VectorH);
   EXPECT_THAT(Vector->headers(), ElementsAre(*VectorH));
 
+  EXPECT_TRUE(stdlib::Symbol::named("std::", "get"));
+  EXPECT_FALSE(stdlib::Symbol::named("std::", "get")->header());
+
   EXPECT_THAT(stdlib::Symbol::named("std::", "basic_iostream")->headers(),
               ElementsAre(stdlib::Header::named("<istream>"),
                           stdlib::Header::named("<iostream>"),