[clang-tools-extra] create new clang-tidy check to add namespaces to symbol references (PR #70621)

[via cfe-commits]

================
@@ -0,0 +1,22 @@
+// RUN: %check_clang_tidy %s readability-use-explicit-namespaces %t
+
+namespace foo
+{
+void doSomething()
+{
+}
+}
+
+void test1()
+{
+        foo::doSomething();
+}
+
+using namespace foo;
+
+void test2()
+{
+	// CHECK-MESSAGES: :[[@LINE+1]]:2: warning: Missing namespace qualifiers foo::
+        doSomething();
+}
+
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EugeneZelenko wrote:

Excessive newline.

https://github.com/llvm/llvm-project/pull/70621