[clang-tidy] Add check performance-faster-string-find

Summary:
Add check performance-faster-string-find.
It replaces single character string literals to character literals in calls to string::find and friends.

Reviewers: alexfh

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D16152

llvm-svn: 260712

2 files changed, 23 insertions, 0 deletions

diff --git a/clang-tools-extra/docs/clang-tidy/checks/list.rst b/clang-tools-extra/docs/clang-tidy/checks/list.rst
index fe1a0225e34..629dd603a69 100644
--- a/clang-tools-extra/docs/clang-tidy/checks/list.rst
+++ b/clang-tools-extra/docs/clang-tidy/checks/list.rst
@@ -80,6 +80,7 @@ Clang-Tidy Checks
    modernize-use-default
    modernize-use-nullptr
    modernize-use-override
+   performance-faster-string-find
    performance-for-range-copy
    performance-implicit-cast-in-loop
    readability-braces-around-statements
diff --git a/clang-tools-extra/docs/clang-tidy/checks/performance-faster-string-find.rst b/clang-tools-extra/docs/clang-tidy/checks/performance-faster-string-find.rst
new file mode 100644
index 00000000000..147f0c3815a
--- /dev/null
+++ b/clang-tools-extra/docs/clang-tidy/checks/performance-faster-string-find.rst
@@ -0,0 +1,22 @@
+.. title:: clang-tidy - performance-faster-string-find
+
+performance-faster-string-find
+==============================
+
+Optimize calls to std::string::find() and friends when the needle passed is
+a single character string literal.
+The character literal overload is more efficient.
+
+By default only `std::basic_string` is considered. This list can be modified by
+passing a `;` separated list of class names using the `StringLikeClasses`
+option. The methods to consired are fixed, though.
+
+Examples:
+
+.. code-block:: c++
+
+  str.find("A");
+
+  // becomes
+
+  str.find('A');