[clang-tools-extra] [clang-tidy] Add new modernize-use-starts-ends-with check (PR #72385)
Nicolas van Kempen via cfe-commits
cfe-commits at lists.llvm.org
Mon Dec 4 01:56:40 PST 2023
https://github.com/nicovank updated https://github.com/llvm/llvm-project/pull/72385
>From c6b5aac2b5a3d90d11a8fc0d092c2e794cff5856 Mon Sep 17 00:00:00 2001
From: Nicolas van Kempen <nvankempen at fb.com>
Date: Wed, 15 Nov 2023 01:13:10 -0800
Subject: [PATCH] [clang-tidy] Add new modernize-use-starts-ends-with check
Match .find() and .rfind() calls compared to 0, and suggests replacing them with
starts_with.
---
.../abseil/StringFindStartswithCheck.h | 5 +-
.../clang-tidy/modernize/CMakeLists.txt | 1 +
.../modernize/ModernizeTidyModule.cpp | 3 +
.../modernize/UseStartsEndsWithCheck.cpp | 109 ++++++++++++
.../modernize/UseStartsEndsWithCheck.h | 37 ++++
clang-tools-extra/docs/ReleaseNotes.rst | 7 +
.../checks/abseil/string-find-startswith.rst | 4 +
.../docs/clang-tidy/checks/list.rst | 1 +
.../checks/modernize/use-starts-ends-with.rst | 22 +++
.../checkers/Inputs/Headers/stddef.h | 2 +-
.../clang-tidy/checkers/Inputs/Headers/string | 16 +-
.../abseil/string-find-startswith.cpp | 2 +-
.../modernize/use-starts-ends-with.cpp | 167 ++++++++++++++++++
.../readability/container-size-empty.cpp | 4 +-
14 files changed, 374 insertions(+), 6 deletions(-)
create mode 100644 clang-tools-extra/clang-tidy/modernize/UseStartsEndsWithCheck.cpp
create mode 100644 clang-tools-extra/clang-tidy/modernize/UseStartsEndsWithCheck.h
create mode 100644 clang-tools-extra/docs/clang-tidy/checks/modernize/use-starts-ends-with.rst
create mode 100644 clang-tools-extra/test/clang-tidy/checkers/modernize/use-starts-ends-with.cpp
diff --git a/clang-tools-extra/clang-tidy/abseil/StringFindStartswithCheck.h b/clang-tools-extra/clang-tidy/abseil/StringFindStartswithCheck.h
index 923b5caece543..de3bd4d422200 100644
--- a/clang-tools-extra/clang-tidy/abseil/StringFindStartswithCheck.h
+++ b/clang-tools-extra/clang-tidy/abseil/StringFindStartswithCheck.h
@@ -21,7 +21,6 @@ namespace clang::tidy::abseil {
// Find string.find(...) == 0 comparisons and suggest replacing with StartsWith.
// FIXME(niko): Add similar check for EndsWith
-// FIXME(niko): Add equivalent modernize checks for C++20's std::starts_With
class StringFindStartswithCheck : public ClangTidyCheck {
public:
using ClangTidyCheck::ClangTidyCheck;
@@ -31,6 +30,10 @@ class StringFindStartswithCheck : public ClangTidyCheck {
void registerMatchers(ast_matchers::MatchFinder *Finder) override;
void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
void storeOptions(ClangTidyOptions::OptionMap &Opts) override;
+ bool isLanguageVersionSupported(const LangOptions &LangOpts) const override {
+ // Prefer modernize-use-starts-ends-with when C++20 is available.
+ return LangOpts.CPlusPlus && !LangOpts.CPlusPlus20;
+ }
private:
const std::vector<StringRef> StringLikeClasses;
diff --git a/clang-tools-extra/clang-tidy/modernize/CMakeLists.txt b/clang-tools-extra/clang-tidy/modernize/CMakeLists.txt
index 717c400c47903..c40065358d2dc 100644
--- a/clang-tools-extra/clang-tidy/modernize/CMakeLists.txt
+++ b/clang-tools-extra/clang-tidy/modernize/CMakeLists.txt
@@ -38,6 +38,7 @@ add_clang_library(clangTidyModernizeModule
UseNoexceptCheck.cpp
UseNullptrCheck.cpp
UseOverrideCheck.cpp
+ UseStartsEndsWithCheck.cpp
UseStdPrintCheck.cpp
UseTrailingReturnTypeCheck.cpp
UseTransparentFunctorsCheck.cpp
diff --git a/clang-tools-extra/clang-tidy/modernize/ModernizeTidyModule.cpp b/clang-tools-extra/clang-tidy/modernize/ModernizeTidyModule.cpp
index 73751cf270506..e994ffd2a75c8 100644
--- a/clang-tools-extra/clang-tidy/modernize/ModernizeTidyModule.cpp
+++ b/clang-tools-extra/clang-tidy/modernize/ModernizeTidyModule.cpp
@@ -39,6 +39,7 @@
#include "UseNoexceptCheck.h"
#include "UseNullptrCheck.h"
#include "UseOverrideCheck.h"
+#include "UseStartsEndsWithCheck.h"
#include "UseStdPrintCheck.h"
#include "UseTrailingReturnTypeCheck.h"
#include "UseTransparentFunctorsCheck.h"
@@ -66,6 +67,8 @@ class ModernizeModule : public ClangTidyModule {
CheckFactories.registerCheck<MakeSharedCheck>("modernize-make-shared");
CheckFactories.registerCheck<MakeUniqueCheck>("modernize-make-unique");
CheckFactories.registerCheck<PassByValueCheck>("modernize-pass-by-value");
+ CheckFactories.registerCheck<UseStartsEndsWithCheck>(
+ "modernize-use-starts-ends-with");
CheckFactories.registerCheck<UseStdPrintCheck>("modernize-use-std-print");
CheckFactories.registerCheck<RawStringLiteralCheck>(
"modernize-raw-string-literal");
diff --git a/clang-tools-extra/clang-tidy/modernize/UseStartsEndsWithCheck.cpp b/clang-tools-extra/clang-tidy/modernize/UseStartsEndsWithCheck.cpp
new file mode 100644
index 0000000000000..062f6e9911dbe
--- /dev/null
+++ b/clang-tools-extra/clang-tidy/modernize/UseStartsEndsWithCheck.cpp
@@ -0,0 +1,109 @@
+//===--- UseStartsEndsWithCheck.cpp - clang-tidy --------------------------===//
+//
+// 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 "UseStartsEndsWithCheck.h"
+
+#include "../utils/OptionsUtils.h"
+#include "clang/Lex/Lexer.h"
+
+#include <string>
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::modernize {
+
+UseStartsEndsWithCheck::UseStartsEndsWithCheck(StringRef Name,
+ ClangTidyContext *Context)
+ : ClangTidyCheck(Name, Context) {}
+
+void UseStartsEndsWithCheck::registerMatchers(MatchFinder *Finder) {
+ const auto ZeroLiteral = integerLiteral(equals(0));
+ const auto HasStartsWithMethodWithName = [](const std::string &Name) {
+ return hasMethod(
+ cxxMethodDecl(hasName(Name), isConst(), parameterCountIs(1))
+ .bind("starts_with_fun"));
+ };
+ const auto HasStartsWithMethod =
+ anyOf(HasStartsWithMethodWithName("starts_with"),
+ HasStartsWithMethodWithName("startsWith"),
+ HasStartsWithMethodWithName("startswith"));
+ const auto ClassWithStartsWithFunction = cxxRecordDecl(anyOf(
+ HasStartsWithMethod, hasAnyBase(hasType(hasCanonicalType(hasDeclaration(
+ cxxRecordDecl(HasStartsWithMethod)))))));
+
+ const auto FindExpr = cxxMemberCallExpr(
+ // A method call with no second argument or the second argument is zero...
+ anyOf(argumentCountIs(1), hasArgument(1, ZeroLiteral)),
+ // ... named find...
+ callee(cxxMethodDecl(hasName("find")).bind("find_fun")),
+ // ... on a class with a starts_with function.
+ on(hasType(
+ hasCanonicalType(hasDeclaration(ClassWithStartsWithFunction)))));
+
+ const auto RFindExpr = cxxMemberCallExpr(
+ // A method call with a second argument of zero...
+ hasArgument(1, ZeroLiteral),
+ // ... named rfind...
+ callee(cxxMethodDecl(hasName("rfind")).bind("find_fun")),
+ // ... on a class with a starts_with function.
+ on(hasType(
+ hasCanonicalType(hasDeclaration(ClassWithStartsWithFunction)))));
+
+ const auto FindOrRFindExpr =
+ cxxMemberCallExpr(anyOf(FindExpr, RFindExpr)).bind("find_expr");
+
+ Finder->addMatcher(
+ // Match [=!]= with a zero on one side and a string.(r?)find on the other.
+ binaryOperator(hasAnyOperatorName("==", "!="),
+ hasOperands(FindOrRFindExpr, ZeroLiteral))
+ .bind("expr"),
+ this);
+}
+
+void UseStartsEndsWithCheck::check(const MatchFinder::MatchResult &Result) {
+ const auto *ComparisonExpr = Result.Nodes.getNodeAs<BinaryOperator>("expr");
+ const auto *FindExpr = Result.Nodes.getNodeAs<CXXMemberCallExpr>("find_expr");
+ const auto *FindFun = Result.Nodes.getNodeAs<CXXMethodDecl>("find_fun");
+ const auto *StartsWithFunction =
+ Result.Nodes.getNodeAs<CXXMethodDecl>("starts_with_fun");
+
+ if (ComparisonExpr->getBeginLoc().isMacroID()) {
+ return;
+ }
+
+ const bool Neg = ComparisonExpr->getOpcode() == BO_NE;
+
+ auto Diagnostic =
+ diag(FindExpr->getBeginLoc(), "use %0 instead of %1() %select{==|!=}2 0")
+ << StartsWithFunction->getName() << FindFun->getName() << Neg;
+
+ // Remove possible zero second argument and ' [!=]= 0' suffix.
+ Diagnostic << FixItHint::CreateReplacement(
+ CharSourceRange::getTokenRange(
+ Lexer::getLocForEndOfToken(FindExpr->getArg(0)->getEndLoc(), 0,
+ *Result.SourceManager, getLangOpts()),
+ ComparisonExpr->getEndLoc()),
+ ")");
+
+ // Remove possible '0 [!=]= ' prefix.
+ Diagnostic << FixItHint::CreateRemoval(CharSourceRange::getCharRange(
+ ComparisonExpr->getBeginLoc(), FindExpr->getBeginLoc()));
+
+ // Replace '(r?)find' with 'starts_with'.
+ Diagnostic << FixItHint::CreateReplacement(
+ CharSourceRange::getTokenRange(FindExpr->getExprLoc(),
+ FindExpr->getExprLoc()),
+ StartsWithFunction->getName());
+
+ // Add possible negation '!'.
+ if (Neg) {
+ Diagnostic << FixItHint::CreateInsertion(FindExpr->getBeginLoc(), "!");
+ }
+}
+
+} // namespace clang::tidy::modernize
diff --git a/clang-tools-extra/clang-tidy/modernize/UseStartsEndsWithCheck.h b/clang-tools-extra/clang-tidy/modernize/UseStartsEndsWithCheck.h
new file mode 100644
index 0000000000000..34e9717768257
--- /dev/null
+++ b/clang-tools-extra/clang-tidy/modernize/UseStartsEndsWithCheck.h
@@ -0,0 +1,37 @@
+//===--- UseStartsEndsWithCheck.h - clang-tidy ------------------*- 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_MODERNIZE_USESTARTSENDSWITHCHECK_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_MODERNIZE_USESTARTSENDSWITHCHECK_H
+
+#include "../ClangTidyCheck.h"
+
+namespace clang::tidy::modernize {
+
+/// Checks whether a ``find`` or ``rfind`` result is compared with 0 and
+/// suggests replacing with ``starts_with`` when the method exists in the class.
+/// Notably, this will work with ``std::string`` and ``std::string_view``.
+///
+/// For the user-facing documentation see:
+/// http://clang.llvm.org/extra/clang-tidy/checks/modernize/use-starts-ends-with.html
+class UseStartsEndsWithCheck : public ClangTidyCheck {
+public:
+ UseStartsEndsWithCheck(StringRef Name, ClangTidyContext *Context);
+ void registerMatchers(ast_matchers::MatchFinder *Finder) override;
+ void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
+ bool isLanguageVersionSupported(const LangOptions &LangOpts) const override {
+ return LangOpts.CPlusPlus;
+ }
+ std::optional<TraversalKind> getCheckTraversalKind() const override {
+ return TK_IgnoreUnlessSpelledInSource;
+ }
+};
+
+} // namespace clang::tidy::modernize
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_MODERNIZE_USESTARTSENDSWITHCHECK_H
diff --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst
index 353c6fe202692..4d6d66bc9240a 100644
--- a/clang-tools-extra/docs/ReleaseNotes.rst
+++ b/clang-tools-extra/docs/ReleaseNotes.rst
@@ -186,6 +186,13 @@ New checks
Replace ``enable_if`` with C++20 requires clauses.
+- New :doc:`modernize-use-starts-ends-with
+ <clang-tidy/checks/modernize/use-starts-ends-with>` check.
+
+ Checks whether a ``find`` or ``rfind`` result is compared with 0 and suggests
+ replacing with ``starts_with`` when the method exists in the class. Notably,
+ this will work with ``std::string`` and ``std::string_view``.
+
- New :doc:`performance-enum-size
<clang-tidy/checks/performance/enum-size>` check.
diff --git a/clang-tools-extra/docs/clang-tidy/checks/abseil/string-find-startswith.rst b/clang-tools-extra/docs/clang-tidy/checks/abseil/string-find-startswith.rst
index c82c38772a5c9..41a7ab500d7ce 100644
--- a/clang-tools-extra/docs/clang-tidy/checks/abseil/string-find-startswith.rst
+++ b/clang-tools-extra/docs/clang-tidy/checks/abseil/string-find-startswith.rst
@@ -8,6 +8,10 @@ corresponding ``std::string_view`` methods) result is compared with 0, and
suggests replacing with ``absl::StartsWith()``. This is both a readability and
performance issue.
+``starts_with`` was added as a built-in function on those types in C++20. If
+available, prefer enabling :doc:`modernize-use-starts-ends-with
+<../modernize/use-starts-ends-with>` instead of this check.
+
.. code-block:: c++
string s = "...";
diff --git a/clang-tools-extra/docs/clang-tidy/checks/list.rst b/clang-tools-extra/docs/clang-tidy/checks/list.rst
index 6f987ba1672e3..df2d5d15238d6 100644
--- a/clang-tools-extra/docs/clang-tidy/checks/list.rst
+++ b/clang-tools-extra/docs/clang-tidy/checks/list.rst
@@ -292,6 +292,7 @@ Clang-Tidy Checks
:doc:`modernize-use-noexcept <modernize/use-noexcept>`, "Yes"
:doc:`modernize-use-nullptr <modernize/use-nullptr>`, "Yes"
:doc:`modernize-use-override <modernize/use-override>`, "Yes"
+ :doc:`modernize-use-starts-ends-with <modernize/use-starts-ends-with>`, "Yes"
:doc:`modernize-use-std-print <modernize/use-std-print>`, "Yes"
:doc:`modernize-use-trailing-return-type <modernize/use-trailing-return-type>`, "Yes"
:doc:`modernize-use-transparent-functors <modernize/use-transparent-functors>`, "Yes"
diff --git a/clang-tools-extra/docs/clang-tidy/checks/modernize/use-starts-ends-with.rst b/clang-tools-extra/docs/clang-tidy/checks/modernize/use-starts-ends-with.rst
new file mode 100644
index 0000000000000..7f8a262d2ab3a
--- /dev/null
+++ b/clang-tools-extra/docs/clang-tidy/checks/modernize/use-starts-ends-with.rst
@@ -0,0 +1,22 @@
+.. title:: clang-tidy - modernize-use-starts-ends-with
+
+modernize-use-starts-ends-with
+==============================
+
+Checks whether a ``find`` or ``rfind`` result is compared with 0 and suggests
+replacing with ``starts_with`` when the method exists in the class. Notably,
+this will work with ``std::string`` and ``std::string_view``.
+
+.. code-block:: c++
+
+ std::string s = "...";
+ if (s.find("prefix") == 0) { /* do something */ }
+ if (s.rfind("prefix", 0) == 0) { /* do something */ }
+
+becomes
+
+.. code-block:: c++
+
+ std::string s = "...";
+ if (s.starts_with("prefix")) { /* do something */ }
+ if (s.starts_with("prefix")) { /* do something */ }
diff --git a/clang-tools-extra/test/clang-tidy/checkers/Inputs/Headers/stddef.h b/clang-tools-extra/test/clang-tidy/checkers/Inputs/Headers/stddef.h
index 24b8ef012d4a0..11feddf0f0676 100644
--- a/clang-tools-extra/test/clang-tidy/checkers/Inputs/Headers/stddef.h
+++ b/clang-tools-extra/test/clang-tidy/checkers/Inputs/Headers/stddef.h
@@ -12,4 +12,4 @@
typedef __PTRDIFF_TYPE__ ptrdiff_t;
typedef __SIZE_TYPE__ size_t;
-#endif _STDDEF_H_
+#endif // _STDDEF_H_
diff --git a/clang-tools-extra/test/clang-tidy/checkers/Inputs/Headers/string b/clang-tools-extra/test/clang-tidy/checkers/Inputs/Headers/string
index d0aac7b78ec93..f2e4159a22451 100644
--- a/clang-tools-extra/test/clang-tidy/checkers/Inputs/Headers/string
+++ b/clang-tools-extra/test/clang-tidy/checkers/Inputs/Headers/string
@@ -10,8 +10,13 @@ typedef unsigned __INT32_TYPE__ char32;
namespace std {
template <typename T>
class allocator {};
+
template <typename T>
class char_traits {};
+
+template <typename C, typename T = char_traits<C>>
+struct basic_string_view;
+
template <typename C, typename T = char_traits<C>, typename A = allocator<C>>
struct basic_string {
typedef size_t size_type;
@@ -52,6 +57,10 @@ struct basic_string {
_Type& insert(size_type pos, const C* s);
_Type& insert(size_type pos, const C* s, size_type n);
+ constexpr bool starts_with(std::basic_string_view<C, T> sv) const noexcept;
+ constexpr bool starts_with(C ch) const noexcept;
+ constexpr bool starts_with(const C* s) const;
+
_Type& operator[](size_type);
const _Type& operator[](size_type) const;
@@ -68,7 +77,7 @@ typedef basic_string<wchar_t> wstring;
typedef basic_string<char16> u16string;
typedef basic_string<char32> u32string;
-template <typename C, typename T = char_traits<C>>
+template <typename C, typename T>
struct basic_string_view {
typedef size_t size_type;
typedef basic_string_view<C, T> _Type;
@@ -86,8 +95,13 @@ struct basic_string_view {
size_type rfind(const C* s, size_type pos, size_type count) const;
size_type rfind(const C* s, size_type pos = npos) const;
+ constexpr bool starts_with(basic_string_view sv) const noexcept;
+ constexpr bool starts_with(C ch) const noexcept;
+ constexpr bool starts_with(const C* s) const;
+
static constexpr size_t npos = -1;
};
+
typedef basic_string_view<char> string_view;
typedef basic_string_view<wchar_t> wstring_view;
typedef basic_string_view<char16> u16string_view;
diff --git a/clang-tools-extra/test/clang-tidy/checkers/abseil/string-find-startswith.cpp b/clang-tools-extra/test/clang-tidy/checkers/abseil/string-find-startswith.cpp
index 417598790bc00..aabb30fe34f78 100644
--- a/clang-tools-extra/test/clang-tidy/checkers/abseil/string-find-startswith.cpp
+++ b/clang-tools-extra/test/clang-tidy/checkers/abseil/string-find-startswith.cpp
@@ -1,4 +1,4 @@
-// RUN: %check_clang_tidy %s abseil-string-find-startswith %t -- \
+// RUN: %check_clang_tidy -std=c++17 %s abseil-string-find-startswith %t -- \
// RUN: -config="{CheckOptions: \
// RUN: {abseil-string-find-startswith.StringLikeClasses: \
// RUN: '::std::basic_string;::std::basic_string_view;::basic_string'}}" \
diff --git a/clang-tools-extra/test/clang-tidy/checkers/modernize/use-starts-ends-with.cpp b/clang-tools-extra/test/clang-tidy/checkers/modernize/use-starts-ends-with.cpp
new file mode 100644
index 0000000000000..65ed9ed895bc4
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/checkers/modernize/use-starts-ends-with.cpp
@@ -0,0 +1,167 @@
+// RUN: %check_clang_tidy -std=c++20 %s modernize-use-starts-ends-with %t -- \
+// RUN: -- -isystem %clang_tidy_headers
+
+#include <string>
+
+std::string foo(std::string);
+std::string bar();
+
+class sub_string : public std::string {};
+class sub_sub_string : public sub_string {};
+
+struct string_like {
+ bool starts_with(const char *s) const;
+ size_t find(const char *s, size_t pos = 0) const;
+};
+
+struct string_like_camel {
+ bool startsWith(const char *s) const;
+ size_t find(const char *s, size_t pos = 0) const;
+};
+
+struct prefer_underscore_version {
+ bool starts_with(const char *s) const;
+ bool startsWith(const char *s) const;
+ size_t find(const char *s, size_t pos = 0) const;
+};
+
+struct prefer_underscore_version_flip {
+ bool startsWith(const char *s) const;
+ bool starts_with(const char *s) const;
+ size_t find(const char *s, size_t pos = 0) const;
+};
+
+struct prefer_underscore_version_inherit : public string_like {
+ bool startsWith(const char *s) const;
+};
+
+void test(std::string s, std::string_view sv, sub_string ss, sub_sub_string sss,
+ string_like sl, string_like_camel slc, prefer_underscore_version puv,
+ prefer_underscore_version_flip puvf,
+ prefer_underscore_version_inherit puvi) {
+ s.find("a") == 0;
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with instead of find() == 0
+ // CHECK-FIXES: s.starts_with("a");
+
+ (((((s)).find("a")))) == ((0));
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: ((s)).starts_with("a");
+
+ (s + "a").find("a") == ((0));
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: (s + "a").starts_with("a");
+
+ s.find(s) == 0;
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: s.starts_with(s);
+
+ s.find("aaa") != 0;
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: !s.starts_with("aaa");
+
+ s.find(foo(foo(bar()))) != 0;
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: !s.starts_with(foo(foo(bar())));
+
+ if (s.find("....") == 0) { /* do something */ }
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: if (s.starts_with("...."))
+
+ 0 != s.find("a");
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: !s.starts_with("a");
+
+ s.rfind("a", 0) == 0;
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with instead of rfind() == 0
+ // CHECK-FIXES: s.starts_with("a");
+
+ s.rfind(s, 0) == 0;
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: s.starts_with(s);
+
+ s.rfind("aaa", 0) != 0;
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: !s.starts_with("aaa");
+
+ s.rfind(foo(foo(bar())), 0) != 0;
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: !s.starts_with(foo(foo(bar())));
+
+ if (s.rfind("....", 0) == 0) { /* do something */ }
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: if (s.starts_with("...."))
+
+ 0 != s.rfind("a", 0);
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: !s.starts_with("a");
+
+ #define STR(x) std::string(x)
+ 0 == STR(s).find("a");
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: STR(s).starts_with("a");
+
+ #define STRING s
+ if (0 == STRING.find("ala")) { /* do something */}
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: if (STRING.starts_with("ala"))
+
+ #define FIND find
+ s.FIND("a") == 0;
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: s.starts_with("a")
+
+ #define PREFIX "a"
+ s.find(PREFIX) == 0;
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: s.starts_with(PREFIX)
+
+ #define ZERO 0
+ s.find("a") == ZERO;
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: s.starts_with("a")
+
+ sv.find("a") == 0;
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: sv.starts_with("a");
+
+ sv.rfind("a", 0) != 0;
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: !sv.starts_with("a");
+
+ ss.find("a") == 0;
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: ss.starts_with("a");
+
+ sss.find("a") == 0;
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: ss.starts_with("a");
+
+ sl.find("a") == 0;
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: sl.starts_with("a");
+
+ slc.find("a") == 0;
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use startsWith
+ // CHECK-FIXES: slc.startsWith("a");
+
+ puv.find("a") == 0;
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: puv.starts_with("a");
+
+ puvf.find("a") == 0;
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use starts_with
+ // CHECK-FIXES: puvf.starts_with("a");
+
+ // Here, the subclass has startsWith, the superclass has starts_with.
+ // We prefer the version from the subclass.
+ puvi.find("a") == 0;
+ // CHECK-MESSAGES: :[[@LINE-1]]:{{[0-9]+}}: warning: use startsWith
+ // CHECK-FIXES: puvi.startsWith("a");
+
+ // Expressions that don't trigger the check are here.
+ #define EQ(x, y) ((x) == (y))
+ EQ(s.find("a"), 0);
+
+ #define DOTFIND(x, y) (x).find(y)
+ DOTFIND(s, "a") == 0;
+}
diff --git a/clang-tools-extra/test/clang-tidy/checkers/readability/container-size-empty.cpp b/clang-tools-extra/test/clang-tidy/checkers/readability/container-size-empty.cpp
index 29ac86cf1b369..3b9e060841830 100644
--- a/clang-tools-extra/test/clang-tidy/checkers/readability/container-size-empty.cpp
+++ b/clang-tools-extra/test/clang-tidy/checkers/readability/container-size-empty.cpp
@@ -528,12 +528,12 @@ template <typename T> void f() {
if (s.size())
;
// CHECK-MESSAGES: :[[@LINE-2]]:7: warning: the 'empty' method should be used to check for emptiness instead of 'size' [readability-container-size-empty]
- // CHECK-MESSAGES: string:28:8: note: method 'basic_string'::empty() defined here
+ // CHECK-MESSAGES: string:{{[0-9]+}}:8: note: method 'basic_string'::empty() defined here
// CHECK-FIXES: {{^ }}if (!s.empty()){{$}}
if (s.length())
;
// CHECK-MESSAGES: :[[@LINE-2]]:7: warning: the 'empty' method should be used to check for emptiness instead of 'length' [readability-container-size-empty]
- // CHECK-MESSAGES: string:28:8: note: method 'basic_string'::empty() defined here
+ // CHECK-MESSAGES: string:{{[0-9]+}}:8: note: method 'basic_string'::empty() defined here
// CHECK-FIXES: {{^ }}if (!s.empty()){{$}}
}
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