[clang-tools-extra] [clang-tidy] Add llvm-regex check (PR #207407)

[via cfe-commits]

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@@ -0,0 +1,88 @@
+//===----------------------------------------------------------------------===//
+//
+// 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 "InvalidRegexPatternCheck.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "llvm/Support/Regex.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::llvm_check {
+
+void InvalidRegexPatternCheck::registerMatchers(MatchFinder *Finder) {
+  // main matcher
+  auto IsConstllvmStringRef = qualType(
+      isConstQualified(), hasUnqualifiedDesugaredType(recordType(hasDeclaration(
+                              cxxRecordDecl(hasName("::llvm::StringRef"))))));
+  auto IsConstStdString = qualType(
+      isConstQualified(), hasUnqualifiedDesugaredType(recordType(hasDeclaration(
+                              cxxRecordDecl(hasName("::std::basic_string"))))));
+  auto GetStringLit = ignoringImplicit(stringLiteral().bind("stringLiteral"));
+  auto GetStringLiteralFromObject =
+      ignoringImplicit(cxxConstructExpr(hasAnyArgument(GetStringLit)));
+  auto IsConstCharPtr = pointerType(pointee(builtinType(), isConstQualified()));
+  auto IsStdStringView = qualType(hasUnqualifiedDesugaredType(recordType(
+      hasDeclaration(cxxRecordDecl(hasName("::std::basic_string_view"))))));
+  auto AnyCastedToStringRef = ignoringImplicit(anyOf(
+      stringLiteral().bind("stringLiteral"),
+      declRefExpr(to(varDecl(hasType(IsConstStdString),
+                             hasInitializer(GetStringLiteralFromObject)))),
+      declRefExpr(to(varDecl(hasType(IsConstllvmStringRef),
+                             hasInitializer(GetStringLiteralFromObject)))),
+      declRefExpr(
+          to(varDecl(hasType(IsConstCharPtr), hasInitializer(GetStringLit)))),
+      declRefExpr(to(varDecl(hasType(IsStdStringView),
+                             hasInitializer(GetStringLiteralFromObject)))),
+      memberExpr(
+          member(fieldDecl(hasType(IsConstStdString),
+                           hasInClassInitializer(GetStringLiteralFromObject)))),
+      memberExpr(member(fieldDecl(hasType(IsConstCharPtr),
+                                  hasInClassInitializer(GetStringLit)))),
+      memberExpr(
+          member(fieldDecl(hasType(IsConstllvmStringRef),
+                           hasInClassInitializer(GetStringLiteralFromObject)))),
----------------
furtib wrote:

Rewritten.

https://github.com/llvm/llvm-project/pull/207407