[clangd] Tune down quality score for class constructors so that it's ranked after...

Summary:
Currently, class constructors have the same score as the class types, and they
are often ranked before class types. This is often not desireable and can
be annoying when snippet is enabled and constructor signatures are added.

Metrics:

```
==================================================================================================
                                        OVERALL
==================================================================================================
  Total measurements: 111117 (+0)
  All measurements:
	MRR: 64.06 (+0.20)	Top-5: 75.73% (+0.14%)	Top-100: 93.71% (+0.01%)
  Full identifiers:
	MRR: 98.25 (+0.55)	Top-5: 99.04% (+0.03%)	Top-100: 99.16% (+0.00%)
  Filter length 0-5:
	MRR:      15.23 (+0.02)		50.50 (-0.02)		65.04 (+0.11)		70.75 (+0.19)		74.37 (+0.25)		79.43 (+0.32)
	Top-5:    40.90% (+0.03%)		74.52% (+0.03%)		87.23% (+0.15%)		91.68% (+0.08%)		93.68% (+0.14%)		95.87% (+0.12%)
	Top-100:  68.21% (+0.02%)		96.28% (+0.07%)		98.43% (+0.00%)		98.72% (+0.00%)		98.74% (+0.01%)		98.81% (+0.00%)
==================================================================================================
                                        DEFAULT
==================================================================================================
  Total measurements: 57535 (+0)
  All measurements:
	MRR: 58.07 (+0.37)	Top-5: 69.94% (+0.26%)	Top-100: 90.14% (+0.03%)
  Full identifiers:
	MRR: 97.13 (+1.05)	Top-5: 98.14% (+0.06%)	Top-100: 98.34% (+0.00%)
  Filter length 0-5:
	MRR:      13.91 (+0.00)		38.53 (+0.01)		55.58 (+0.21)		63.63 (+0.30)		69.23 (+0.47)		72.87 (+0.60)
	Top-5:    24.99% (+0.00%)		62.70% (+0.06%)		82.80% (+0.30%)		88.66% (+0.16%)		92.02% (+0.27%)		93.53% (+0.21%)
	Top-100:  51.56% (+0.05%)		93.19% (+0.13%)		97.30% (+0.00%)		97.81% (+0.00%)		97.85% (+0.01%)		97.79% (+0.00%)
```

Remark:
- The full-id completions have +1.05 MRR improvement.
- There is no noticeable impact on EXPLICIT_MEMBER_ACCESS and WANT_LOCAL.

Reviewers: sammccall

Subscribers: ilya-biryukov, MaskRay, jkorous, arphaman, cfe-commits

Differential Revision: https://reviews.llvm.org/D49667

llvm-svn: 337816

diff --git a/clang-tools-extra/clangd/Quality.cpp b/clang-tools-extra/clangd/Quality.cpp
index 1dcd20522d3802a5a92a745e0476d5c810261a30..1b64f9a9a956289057a275775c8892a69575c6b4 100644 (file)
--- a/clang-tools-extra/clangd/Quality.cpp
+++ b/clang-tools-extra/clangd/Quality.cpp
@@ -67,6 +67,7 @@ static SymbolQualitySignals::SymbolCategory categorize(const NamedDecl &ND) {
     MAP(TypeDecl, Type);
     MAP(TypeAliasTemplateDecl, Type);
     MAP(ClassTemplateDecl, Type);
+    MAP(CXXConstructorDecl, Constructor);
     MAP(ValueDecl, Variable);
     MAP(VarTemplateDecl, Variable);
     MAP(FunctionDecl, Function);
@@ -96,6 +97,8 @@ categorize(const CodeCompletionResult &R) {
     return SymbolQualitySignals::Type;
   case CXCursor_MemberRef:
     return SymbolQualitySignals::Variable;
+  case CXCursor_Constructor:
+    return SymbolQualitySignals::Constructor;
   default:
     return SymbolQualitySignals::Keyword;
   }
@@ -124,10 +127,11 @@ categorize(const index::SymbolInfo &D) {
   case index::SymbolKind::InstanceProperty:
   case index::SymbolKind::ClassProperty:
   case index::SymbolKind::StaticProperty:
-  case index::SymbolKind::Constructor:
   case index::SymbolKind::Destructor:
   case index::SymbolKind::ConversionFunction:
     return SymbolQualitySignals::Function;
+  case index::SymbolKind::Constructor:
+    return SymbolQualitySignals::Constructor;
   case index::SymbolKind::Variable:
   case index::SymbolKind::Field:
   case index::SymbolKind::EnumConstant:
@@ -210,6 +214,7 @@ float SymbolQualitySignals::evaluate() const {
     Score *= 0.2f;
     break;
   case Unknown:
+  case Constructor: // No boost constructors so they are after class types.
     break;
   }
 

diff --git a/clang-tools-extra/clangd/Quality.h b/clang-tools-extra/clangd/Quality.h
index 10a0a3ea20d304c000d6d897f858224dbb7e81a0..0aed496be6a01626e662ef64f1a8f7833cc07299 100644 (file)
--- a/clang-tools-extra/clangd/Quality.h
+++ b/clang-tools-extra/clangd/Quality.h
@@ -58,6 +58,7 @@ struct SymbolQualitySignals {
     Macro,
     Type,
     Function,
+    Constructor,
     Namespace,
     Keyword,
   } Category = Unknown;

diff --git a/clang-tools-extra/unittests/clangd/QualityTests.cpp b/clang-tools-extra/unittests/clangd/QualityTests.cpp
index a237e2fef8669104aa9dc4c74a130cd817416dac..153eef49822123993efd02f69e5139f024b23890 100644 (file)
--- a/clang-tools-extra/unittests/clangd/QualityTests.cpp
+++ b/clang-tools-extra/unittests/clangd/QualityTests.cpp
@@ -23,6 +23,7 @@
 #include "TestTU.h"
 #include "clang/AST/Decl.h"
 #include "clang/AST/DeclCXX.h"
+#include "clang/AST/Type.h"
 #include "clang/Sema/CodeCompleteConsumer.h"
 #include "llvm/Support/Casting.h"
 #include "gmock/gmock.h"
@@ -185,13 +186,16 @@ TEST(QualityTests, SymbolQualitySignalsSanity) {
   EXPECT_GT(WithReferences.evaluate(), Default.evaluate());
   EXPECT_GT(ManyReferences.evaluate(), WithReferences.evaluate());
 
-  SymbolQualitySignals Keyword, Variable, Macro;
+  SymbolQualitySignals Keyword, Variable, Macro, Constructor, Function;
   Keyword.Category = SymbolQualitySignals::Keyword;
   Variable.Category = SymbolQualitySignals::Variable;
   Macro.Category = SymbolQualitySignals::Macro;
+  Constructor.Category = SymbolQualitySignals::Constructor;
+  Function.Category = SymbolQualitySignals::Function;
   EXPECT_GT(Variable.evaluate(), Default.evaluate());
   EXPECT_GT(Keyword.evaluate(), Variable.evaluate());
   EXPECT_LT(Macro.evaluate(), Default.evaluate());
+  EXPECT_LT(Constructor.evaluate(), Function.evaluate());
 }
 
 TEST(QualityTests, SymbolRelevanceSignalsSanity) {
@@ -317,6 +321,31 @@ TEST(QualityTests, IsInstanceMember) {
   EXPECT_TRUE(Rel.IsInstanceMember);
 }
 
+TEST(QualityTests, ConstructorQuality) {
+  auto Header = TestTU::withHeaderCode(R"cpp(
+    class Foo {
+    public:
+      Foo(int);
+    };
+  )cpp");
+  auto Symbols = Header.headerSymbols();
+  auto AST = Header.build();
+
+  const NamedDecl *CtorDecl = &findAnyDecl(AST, [](const NamedDecl &ND) {
+    return (ND.getQualifiedNameAsString() == "Foo::Foo") &&
+           llvm::isa<CXXConstructorDecl>(&ND);
+  });
+
+  SymbolQualitySignals Q;
+  Q.merge(CodeCompletionResult(CtorDecl, /*Priority=*/0));
+  EXPECT_EQ(Q.Category, SymbolQualitySignals::Constructor);
+
+  Q.Category = SymbolQualitySignals::Unknown;
+  const Symbol &CtorSym = findSymbol(Symbols, "Foo::Foo");
+  Q.merge(CtorSym);
+  EXPECT_EQ(Q.Category, SymbolQualitySignals::Constructor);
+}
+
 } // namespace
 } // namespace clangd
 } // namespace clang