[clangd] Fix crash on hover over large UL enums

Author: MythreyaK

clang-tools-extra/clangd/Hover.cpp

@@ -451,7 +451,7 @@ std::optional<std::string> printExprValue(const Expr *E,
 
   // Show enums symbolically, not numerically like APValue::printPretty().
   if (T->isEnumeralType() && Constant.Val.isInt() &&
-      Constant.Val.getInt().getSignificantBits() <= 64) {
+      Constant.Val.getInt().isRepresentableByInt64()) {
     // Compare to int64_t to avoid bit-width match requirements.
     int64_t Val = Constant.Val.getInt().getExtValue();
     for (const EnumConstantDecl *ECD : T->castAsEnumDecl()->enumerators())
@@ -462,7 +462,7 @@ std::optional<std::string> printExprValue(const Expr *E,
   }
   // Show hex value of integers if they're at least 10 (or negative!)
   if (T->isIntegralOrEnumerationType() && Constant.Val.isInt() &&
-      Constant.Val.getInt().getSignificantBits() <= 64 &&
+      Constant.Val.getInt().isRepresentableByInt64() &&
       Constant.Val.getInt().uge(10))
     return llvm::formatv("{0} ({1})", Constant.Val.getAsString(Ctx, T),
                          printHex(Constant.Val.getInt()))

clang-tools-extra/clangd/unittests/HoverTests.cpp

@@ -5015,6 +5015,65 @@ TEST(Hover, FunctionParameters) {
   }
 }
 
+TEST(Hover, GH2381) {
+  Annotations Code(R"cpp(
+  struct Foo {
+    enum Bar {
+      A = -42UL,
+      B = ~0UL,
+      C = 0xFFFFFFFFFFFFFFFFUL,
+    };
+  };
+  constexpr auto va$a^ = Foo::A;
+  constexpr auto vb$b^ = Foo::B;
+  constexpr auto vc$c^ = Foo::C;
+  )cpp");
+
+  TestTU TU = TestTU::withCode(Code.code());
+  auto AST = TU.build();
+
+  {
+    auto H = getHover(AST, Code.point("a"), format::getLLVMStyle(), nullptr);
+
+    ASSERT_TRUE(H);
+    EXPECT_EQ(H->Name, "va");
+    EXPECT_EQ(H->Kind, index::SymbolKind::Variable);
+    EXPECT_EQ(H->NamespaceScope, "");
+    EXPECT_EQ(H->LocalScope, "");
+    EXPECT_EQ(H->Type, "const Foo::Bar");
+    EXPECT_EQ(H->Definition, "constexpr auto va = Foo::A");
+    // FIXME: Should be "A (FFFFFFFFFFFFFFD6)
+    EXPECT_EQ(H->Value, "18446744073709551574");
+  }
+
+  {
+    auto H = getHover(AST, Code.point("b"), format::getLLVMStyle(), nullptr);
+
+    ASSERT_TRUE(H);
+    EXPECT_EQ(H->Name, "vb");
+    EXPECT_EQ(H->Kind, index::SymbolKind::Variable);
+    EXPECT_EQ(H->NamespaceScope, "");
+    EXPECT_EQ(H->LocalScope, "");
+    EXPECT_EQ(H->Type, "const Foo::Bar");
+    EXPECT_EQ(H->Definition, "constexpr auto vb = Foo::B");
+    // FIXME: Should be "B (0xFFFFFFFFFFFFFFFF)");
+    EXPECT_EQ(H->Value, "18446744073709551615");
+  }
+
+  {
+    auto H = getHover(AST, Code.point("c"), format::getLLVMStyle(), nullptr);
+
+    ASSERT_TRUE(H);
+    EXPECT_EQ(H->Name, "vc");
+    EXPECT_EQ(H->Kind, index::SymbolKind::Variable);
+    EXPECT_EQ(H->NamespaceScope, "");
+    EXPECT_EQ(H->LocalScope, "");
+    EXPECT_EQ(H->Type, "const Foo::Bar");
+    EXPECT_EQ(H->Definition, "constexpr auto vc = Foo::C");
+    // FIXME: Should be "C (0xFFFFFFFFFFFFFFFF)");
+    EXPECT_EQ(H->Value, "18446744073709551615");
+  }
+}
 } // namespace
 } // namespace clangd
 } // namespace clang