[clang-tools-extra] [llvm] [clangd] Add CodeAction to swap operands to binary operators (PR #78999)
Tor Shepherd via cfe-commits
cfe-commits at lists.llvm.org
Sun Feb 11 11:46:23 PST 2024
https://github.com/torshepherd updated https://github.com/llvm/llvm-project/pull/78999
>From 6abe2b5af090329bfca42d144597fbd5ca41d511 Mon Sep 17 00:00:00 2001
From: Tor Shepherd <tor.aksel.shepherd at gmail.com>
Date: Sun, 21 Jan 2024 17:53:31 -0500
Subject: [PATCH] [clangd] Swap binary operands
---
.../clangd/refactor/tweaks/CMakeLists.txt | 1 +
.../refactor/tweaks/SwapBinaryOperands.cpp | 210 ++++++++++++++++++
.../clangd/unittests/CMakeLists.txt | 1 +
.../tweaks/SwapBinaryOperandsTests.cpp | 38 ++++
.../clangd/refactor/tweaks/BUILD.gn | 1 +
.../clangd/unittests/BUILD.gn | 1 +
6 files changed, 252 insertions(+)
create mode 100644 clang-tools-extra/clangd/refactor/tweaks/SwapBinaryOperands.cpp
create mode 100644 clang-tools-extra/clangd/unittests/tweaks/SwapBinaryOperandsTests.cpp
diff --git a/clang-tools-extra/clangd/refactor/tweaks/CMakeLists.txt b/clang-tools-extra/clangd/refactor/tweaks/CMakeLists.txt
index 2e948c23569f68..59475b0dfd3d22 100644
--- a/clang-tools-extra/clangd/refactor/tweaks/CMakeLists.txt
+++ b/clang-tools-extra/clangd/refactor/tweaks/CMakeLists.txt
@@ -29,6 +29,7 @@ add_clang_library(clangDaemonTweaks OBJECT
RemoveUsingNamespace.cpp
ScopifyEnum.cpp
SpecialMembers.cpp
+ SwapBinaryOperands.cpp
SwapIfBranches.cpp
LINK_LIBS
diff --git a/clang-tools-extra/clangd/refactor/tweaks/SwapBinaryOperands.cpp b/clang-tools-extra/clangd/refactor/tweaks/SwapBinaryOperands.cpp
new file mode 100644
index 00000000000000..2241b0ac37b52a
--- /dev/null
+++ b/clang-tools-extra/clangd/refactor/tweaks/SwapBinaryOperands.cpp
@@ -0,0 +1,210 @@
+//===--- SwapBinaryOperands.cpp ----------------------------------*- C++-*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+#include "ParsedAST.h"
+#include "SourceCode.h"
+#include "refactor/Tweak.h"
+#include "support/Logger.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/Expr.h"
+#include "clang/AST/OperationKinds.h"
+#include "clang/AST/Stmt.h"
+#include "clang/Basic/LangOptions.h"
+#include "clang/Basic/SourceLocation.h"
+#include "clang/Basic/SourceManager.h"
+#include "clang/Tooling/Core/Replacement.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/Casting.h"
+#include "llvm/Support/Error.h"
+
+namespace clang {
+namespace clangd {
+namespace {
+/// Check whether it makes logical sense to swap operands to an operator.
+/// Assignment or member access operators are rarely swappable
+/// while keeping the meaning intact, whereas comparison operators, mathematical
+/// operators, etc. are often desired to be swappable for readability, avoiding
+/// bugs by assigning to nullptr when comparison was desired, etc.
+auto isOpSwappable(const BinaryOperatorKind Opcode) -> bool {
+ switch (Opcode) {
+ case BinaryOperatorKind::BO_Mul:
+ case BinaryOperatorKind::BO_Add:
+ case BinaryOperatorKind::BO_Cmp:
+ case BinaryOperatorKind::BO_LT:
+ case BinaryOperatorKind::BO_GT:
+ case BinaryOperatorKind::BO_LE:
+ case BinaryOperatorKind::BO_GE:
+ case BinaryOperatorKind::BO_EQ:
+ case BinaryOperatorKind::BO_NE:
+ case BinaryOperatorKind::BO_And:
+ case BinaryOperatorKind::BO_Xor:
+ case BinaryOperatorKind::BO_Or:
+ case BinaryOperatorKind::BO_LAnd:
+ case BinaryOperatorKind::BO_LOr:
+ case BinaryOperatorKind::BO_Comma:
+ return true;
+ // Noncommutative operators:
+ case BinaryOperatorKind::BO_Div:
+ case BinaryOperatorKind::BO_Sub:
+ case BinaryOperatorKind::BO_Shl:
+ case BinaryOperatorKind::BO_Shr:
+ case BinaryOperatorKind::BO_Rem:
+ // Member access:
+ case BinaryOperatorKind::BO_PtrMemD:
+ case BinaryOperatorKind::BO_PtrMemI:
+ // Assignment:
+ case BinaryOperatorKind::BO_Assign:
+ case BinaryOperatorKind::BO_MulAssign:
+ case BinaryOperatorKind::BO_DivAssign:
+ case BinaryOperatorKind::BO_RemAssign:
+ case BinaryOperatorKind::BO_AddAssign:
+ case BinaryOperatorKind::BO_SubAssign:
+ case BinaryOperatorKind::BO_ShlAssign:
+ case BinaryOperatorKind::BO_ShrAssign:
+ case BinaryOperatorKind::BO_AndAssign:
+ case BinaryOperatorKind::BO_XorAssign:
+ case BinaryOperatorKind::BO_OrAssign:
+ return false;
+ }
+ return false;
+}
+
+/// Some operators are asymmetric and need to be flipped when swapping their
+/// operands
+/// @param[out] Opcode the opcode to potentially swap
+/// If the opcode does not need to be swapped or is not swappable, does nothing
+void swapOperator(BinaryOperatorKind &Opcode) {
+ switch (Opcode) {
+ case BinaryOperatorKind::BO_LT:
+ Opcode = BinaryOperatorKind::BO_GT;
+ return;
+ case BinaryOperatorKind::BO_GT:
+ Opcode = BinaryOperatorKind::BO_LT;
+ return;
+ case BinaryOperatorKind::BO_LE:
+ Opcode = BinaryOperatorKind::BO_GE;
+ return;
+ case BinaryOperatorKind::BO_GE:
+ Opcode = BinaryOperatorKind::BO_LE;
+ return;
+ case BinaryOperatorKind::BO_Mul:
+ case BinaryOperatorKind::BO_Add:
+ case BinaryOperatorKind::BO_Cmp:
+ case BinaryOperatorKind::BO_EQ:
+ case BinaryOperatorKind::BO_NE:
+ case BinaryOperatorKind::BO_And:
+ case BinaryOperatorKind::BO_Xor:
+ case BinaryOperatorKind::BO_Or:
+ case BinaryOperatorKind::BO_LAnd:
+ case BinaryOperatorKind::BO_LOr:
+ case BinaryOperatorKind::BO_Comma:
+ case BinaryOperatorKind::BO_Div:
+ case BinaryOperatorKind::BO_Sub:
+ case BinaryOperatorKind::BO_Shl:
+ case BinaryOperatorKind::BO_Shr:
+ case BinaryOperatorKind::BO_Rem:
+ case BinaryOperatorKind::BO_PtrMemD:
+ case BinaryOperatorKind::BO_PtrMemI:
+ case BinaryOperatorKind::BO_Assign:
+ case BinaryOperatorKind::BO_MulAssign:
+ case BinaryOperatorKind::BO_DivAssign:
+ case BinaryOperatorKind::BO_RemAssign:
+ case BinaryOperatorKind::BO_AddAssign:
+ case BinaryOperatorKind::BO_SubAssign:
+ case BinaryOperatorKind::BO_ShlAssign:
+ case BinaryOperatorKind::BO_ShrAssign:
+ case BinaryOperatorKind::BO_AndAssign:
+ case BinaryOperatorKind::BO_XorAssign:
+ case BinaryOperatorKind::BO_OrAssign:
+ return;
+ }
+}
+
+/// Swaps the operands to a binary operator
+/// Before:
+/// x != nullptr
+/// ^ ^^^^^^^
+/// After:
+/// nullptr != x
+class SwapBinaryOperands : public Tweak {
+public:
+ const char *id() const final;
+
+ bool prepare(const Selection &Inputs) override;
+ Expected<Effect> apply(const Selection &Inputs) override;
+ std::string title() const override {
+ return llvm::formatv("Swap operands to {0}",
+ Op ? Op->getOpcodeStr() : "binary operator");
+ }
+ llvm::StringLiteral kind() const override {
+ return CodeAction::REFACTOR_KIND;
+ }
+ bool hidden() const override { return false; }
+
+private:
+ const BinaryOperator *Op;
+};
+
+REGISTER_TWEAK(SwapBinaryOperands)
+
+bool SwapBinaryOperands::prepare(const Selection &Inputs) {
+ for (const SelectionTree::Node *N = Inputs.ASTSelection.commonAncestor();
+ N && !Op; N = N->Parent) {
+ // Stop once we hit a block, e.g. a lambda in the if condition.
+ if (llvm::isa_and_nonnull<CompoundStmt>(N->ASTNode.get<Stmt>()))
+ return false;
+ Op = dyn_cast_or_null<BinaryOperator>(N->ASTNode.get<Stmt>());
+ // If we hit upon a nonswappable binary operator, ignore and keep going
+ if (Op && !isOpSwappable(Op->getOpcode())) {
+ Op = nullptr;
+ }
+ }
+ return Op != nullptr;
+}
+
+Expected<Tweak::Effect> SwapBinaryOperands::apply(const Selection &Inputs) {
+ auto &Ctx = Inputs.AST->getASTContext();
+ auto &SrcMgr = Inputs.AST->getSourceManager();
+
+ auto LHSRng = toHalfOpenFileRange(SrcMgr, Ctx.getLangOpts(),
+ Op->getLHS()->getSourceRange());
+ if (!LHSRng)
+ return error(
+ "Could not obtain range of the 'lhs' of the operator. Macros?");
+ auto RHSRng = toHalfOpenFileRange(SrcMgr, Ctx.getLangOpts(),
+ Op->getRHS()->getSourceRange());
+ if (!RHSRng)
+ return error(
+ "Could not obtain range of the 'rhs' of the operator. Macros?");
+ auto OpRng =
+ toHalfOpenFileRange(SrcMgr, Ctx.getLangOpts(), Op->getOperatorLoc());
+ if (!OpRng)
+ return error("Could not obtain range of the operator itself. Macros?");
+
+ auto LHSCode = toSourceCode(SrcMgr, *LHSRng);
+ auto RHSCode = toSourceCode(SrcMgr, *RHSRng);
+ auto OperatorCode = toSourceCode(SrcMgr, *OpRng);
+
+ tooling::Replacements Result;
+ if (auto Err = Result.add(tooling::Replacement(
+ Ctx.getSourceManager(), LHSRng->getBegin(), LHSCode.size(), RHSCode)))
+ return std::move(Err);
+ if (auto Err = Result.add(tooling::Replacement(
+ Ctx.getSourceManager(), RHSRng->getBegin(), RHSCode.size(), LHSCode)))
+ return std::move(Err);
+ auto SwappedOperator = Op->getOpcode();
+ swapOperator(SwappedOperator);
+ if (auto Err = Result.add(tooling::Replacement(
+ Ctx.getSourceManager(), OpRng->getBegin(), OperatorCode.size(),
+ Op->getOpcodeStr(SwappedOperator))))
+ return std::move(Err);
+ return Effect::mainFileEdit(SrcMgr, std::move(Result));
+}
+
+} // namespace
+} // namespace clangd
+} // namespace clang
diff --git a/clang-tools-extra/clangd/unittests/CMakeLists.txt b/clang-tools-extra/clangd/unittests/CMakeLists.txt
index 9cd195eaf164fb..b2d8cc13ed8e07 100644
--- a/clang-tools-extra/clangd/unittests/CMakeLists.txt
+++ b/clang-tools-extra/clangd/unittests/CMakeLists.txt
@@ -134,6 +134,7 @@ add_unittest(ClangdUnitTests ClangdTests
tweaks/ScopifyEnumTests.cpp
tweaks/ShowSelectionTreeTests.cpp
tweaks/SpecialMembersTests.cpp
+ tweaks/SwapBinaryOperandsTests.cpp
tweaks/SwapIfBranchesTests.cpp
tweaks/TweakTesting.cpp
tweaks/TweakTests.cpp
diff --git a/clang-tools-extra/clangd/unittests/tweaks/SwapBinaryOperandsTests.cpp b/clang-tools-extra/clangd/unittests/tweaks/SwapBinaryOperandsTests.cpp
new file mode 100644
index 00000000000000..bbb2a576af6eb9
--- /dev/null
+++ b/clang-tools-extra/clangd/unittests/tweaks/SwapBinaryOperandsTests.cpp
@@ -0,0 +1,38 @@
+//===-- SwapBinaryOperandsTests.cpp -----------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "TweakTesting.h"
+#include "gmock/gmock-matchers.h"
+#include "gmock/gmock.h"
+#include "gtest/gtest.h"
+
+namespace clang {
+namespace clangd {
+namespace {
+
+TWEAK_TEST(SwapBinaryOperands);
+
+TEST_F(SwapBinaryOperandsTest, Test) {
+ Context = Function;
+ EXPECT_EQ(apply("int *p = nullptr; bool c = ^p == nullptr;"),
+ "int *p = nullptr; bool c = nullptr == p;");
+ EXPECT_EQ(apply("int *p = nullptr; bool c = p ^== nullptr;"),
+ "int *p = nullptr; bool c = nullptr == p;");
+ EXPECT_EQ(apply("int x = 3; bool c = ^x >= 5;"),
+ "int x = 3; bool c = 5 <= x;");
+ EXPECT_EQ(apply("int x = 3; bool c = x >^= 5;"),
+ "int x = 3; bool c = 5 <= x;");
+ EXPECT_EQ(apply("int x = 3; bool c = x >=^ 5;"),
+ "int x = 3; bool c = 5 <= x;");
+ EXPECT_EQ(apply("int x = 3; bool c = x >=^ 5;"),
+ "int x = 3; bool c = 5 <= x;");
+}
+
+} // namespace
+} // namespace clangd
+} // namespace clang
diff --git a/llvm/utils/gn/secondary/clang-tools-extra/clangd/refactor/tweaks/BUILD.gn b/llvm/utils/gn/secondary/clang-tools-extra/clangd/refactor/tweaks/BUILD.gn
index 255dca3a6015a5..8d19295b4d3d84 100644
--- a/llvm/utils/gn/secondary/clang-tools-extra/clangd/refactor/tweaks/BUILD.gn
+++ b/llvm/utils/gn/secondary/clang-tools-extra/clangd/refactor/tweaks/BUILD.gn
@@ -35,6 +35,7 @@ source_set("tweaks") {
"RemoveUsingNamespace.cpp",
"ScopifyEnum.cpp",
"SpecialMembers.cpp",
+ "SwapBinaryOperands.cpp",
"SwapIfBranches.cpp",
]
}
diff --git a/llvm/utils/gn/secondary/clang-tools-extra/clangd/unittests/BUILD.gn b/llvm/utils/gn/secondary/clang-tools-extra/clangd/unittests/BUILD.gn
index 90b231b5796d27..686ef7f63775bc 100644
--- a/llvm/utils/gn/secondary/clang-tools-extra/clangd/unittests/BUILD.gn
+++ b/llvm/utils/gn/secondary/clang-tools-extra/clangd/unittests/BUILD.gn
@@ -149,6 +149,7 @@ unittest("ClangdTests") {
"tweaks/ScopifyEnumTests.cpp",
"tweaks/ShowSelectionTreeTests.cpp",
"tweaks/SpecialMembersTests.cpp",
+ "tweaks/SwapBinaryOperandsTests.cpp",
"tweaks/SwapIfBranchesTests.cpp",
"tweaks/TweakTesting.cpp",
"tweaks/TweakTests.cpp",
More information about the cfe-commits
mailing list