[cxx-interop] Add support for C++ comparison operators.

Adds support for C++ operators: `<`, `>`, `==`, `!=`, `<=`, and `>=`.

Author: zoecarver

lib/ClangImporter/ImportName.cpp

@@ -1430,6 +1430,12 @@ ImportedName NameImporter::importNameImpl(const clang::NamedDecl *D,
     case clang::OverloadedOperatorKind::OO_GreaterGreater:
     case clang::OverloadedOperatorKind::OO_AmpAmp:
     case clang::OverloadedOperatorKind::OO_PipePipe:
+    case clang::OverloadedOperatorKind::OO_Less:
+    case clang::OverloadedOperatorKind::OO_Greater:
+    case clang::OverloadedOperatorKind::OO_EqualEqual:
+    case clang::OverloadedOperatorKind::OO_ExclaimEqual:
+    case clang::OverloadedOperatorKind::OO_LessEqual:
+    case clang::OverloadedOperatorKind::OO_GreaterEqual:
       if (auto FD = dyn_cast<clang::FunctionDecl>(D)) {
         baseName = clang::getOperatorSpelling(op);
         isFunction = true;

test/Interop/Cxx/operators/Inputs/non-member-inline.h

@@ -41,6 +41,30 @@ inline IntBox operator>>(IntBox lhs, IntBox rhs) {
   return IntBox{.value = lhs.value >> rhs.value};
 }
 
+inline bool operator<(IntBox lhs, IntBox rhs) {
+  return lhs.value < rhs.value;
+}
+
+inline bool operator>(IntBox lhs, IntBox rhs) {
+  return lhs.value > rhs.value;
+}
+
+inline bool operator==(IntBox lhs, IntBox rhs) {
+  return lhs.value == rhs.value;
+}
+
+inline bool operator!=(IntBox lhs, IntBox rhs) {
+  return lhs.value != rhs.value;
+}
+
+inline bool operator<=(IntBox lhs, IntBox rhs) {
+  return lhs.value == rhs.value;
+}
+
+inline bool operator>=(IntBox lhs, IntBox rhs) {
+  return lhs.value != rhs.value;
+}
+
 struct BoolBox {
   bool value;
 };

test/Interop/Cxx/operators/non-member-inline-module-interface.swift

@@ -9,6 +9,12 @@
 // CHECK-NEXT: func | (lhs: IntBox, rhs: IntBox) -> IntBox
 // CHECK-NEXT: func << (lhs: IntBox, rhs: IntBox) -> IntBox
 // CHECK-NEXT: func >> (lhs: IntBox, rhs: IntBox) -> IntBox
+// CHECK-NEXT: func < (lhs: IntBox, rhs: IntBox) -> Bool
+// CHECK-NEXT: func > (lhs: IntBox, rhs: IntBox) -> Bool
+// CHECK-NEXT: func == (lhs: IntBox, rhs: IntBox) -> Bool
+// CHECK-NEXT: func != (lhs: IntBox, rhs: IntBox) -> Bool
+// CHECK-NEXT: func <= (lhs: IntBox, rhs: IntBox) -> Bool
+// CHECK-NEXT: func >= (lhs: IntBox, rhs: IntBox) -> Bool
 
 // CHECK:      func && (lhs: BoolBox, rhs: BoolBox) -> BoolBox
 // CHECK-NEXT: func || (lhs: BoolBox, rhs: BoolBox) -> BoolBox

test/Interop/Cxx/operators/non-member-inline-typechecker.swift

@@ -14,6 +14,12 @@ let resultAmp = lhs & rhs
 let resultPipe = lhs | rhs
 let resultLessLess = lhs << rhs
 let resultGreaterGreater = lhs >> rhs
+let resultLess = lhs < rhs
+let resultGreater = lhs > rhs
+let resultEqualEqual = lhs == rhs
+let resultExclaimEqual = lhs != rhs
+let resultLessEqual = lhs <= rhs
+let resultGreaterEqual = lhs >= rhs
 
 var lhsBool = BoolBox(value: true)
 var rhsBool = BoolBox(value: false)

test/Interop/Cxx/operators/non-member-inline.swift

@@ -106,4 +106,58 @@ OperatorsTestSuite.test("pipe pipe (||)") {
   expectEqual(true, result.value)
 }
 
+OperatorsTestSuite.test("less (<)") {
+  let lhs = IntBox(value: 5)
+  let rhs = IntBox(value: 6)
+
+  let result = lhs < rhs
+
+  expectEqual(true, result)
+}
+
+OperatorsTestSuite.test("greater (>)") {
+  let lhs = IntBox(value: 5)
+  let rhs = IntBox(value: 6)
+
+  let result = lhs > rhs
+
+  expectEqual(false, result)
+}
+
+OperatorsTestSuite.test("equal equal (==)") {
+  let lhs = IntBox(value: 5)
+  let rhs = IntBox(value: 5)
+
+  let result = lhs == rhs
+
+  expectEqual(true, result)
+}
+
+OperatorsTestSuite.test("exclaim equal (!=)") {
+  let lhs = IntBox(value: 5)
+  let rhs = IntBox(value: 5)
+
+  let result = lhs != rhs
+
+  expectEqual(false, result)
+}
+
+OperatorsTestSuite.test("less equal (<=)") {
+  let lhs = IntBox(value: 5)
+  let rhs = IntBox(value: 5)
+
+  let result = lhs <= rhs
+
+  expectEqual(true, result)
+}
+
+OperatorsTestSuite.test("greater equal (>=)") {
+  let lhs = IntBox(value: 6)
+  let rhs = IntBox(value: 5)
+
+  let result = lhs >= rhs
+
+  expectEqual(true, result)
+}
+
 runAllTests()