1 files changed, 36 insertions, 0 deletions
diff --git a/build/clang-plugin/ExplicitImplicitChecker.cpp b/build/clang-plugin/ExplicitImplicitChecker.cpp
new file mode 100644
index 0000000000..e0620f502f
--- /dev/null
+++ b/build/clang-plugin/ExplicitImplicitChecker.cpp
@@ -0,0 +1,36 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "ExplicitImplicitChecker.h"
+#include "CustomMatchers.h"
+
+void ExplicitImplicitChecker::registerMatchers(MatchFinder *AstMatcher) {
+  AstMatcher->addMatcher(
+      cxxConstructorDecl(
+          isInterestingImplicitCtor(),
+          ofClass(allOf(isConcreteClass(), decl().bind("class"))),
+          unless(isMarkedImplicit()))
+          .bind("ctor"),
+      this);
+}
+
+void ExplicitImplicitChecker::check(const MatchFinder::MatchResult &Result) {
+  // We've already checked everything in the matcher, so we just have to report
+  // the error.
+
+  const CXXConstructorDecl *Ctor =
+      Result.Nodes.getNodeAs<CXXConstructorDecl>("ctor");
+  const CXXRecordDecl *Declaration =
+      Result.Nodes.getNodeAs<CXXRecordDecl>("class");
+
+  FixItHint FixItHint =
+      FixItHint::CreateInsertion(Ctor->getLocation(), "explicit ");
+  diag(Ctor->getLocation(), "bad implicit conversion constructor for %0",
+       DiagnosticIDs::Error)
+      << Declaration->getDeclName();
+  diag(Ctor->getLocation(),
+       "consider adding the explicit keyword to the constructor",
+       DiagnosticIDs::Note)
+      << FixItHint;
+}