[clang-tools-extra] [clang-tidy] add new check readability-enum-initial-value (PR #86129)

[Julian Schmidt via cfe-commits]

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@@ -0,0 +1,27 @@
+// RUN: %check_clang_tidy %s readability-enum-initial-value %t
+
+enum EError {
+  // CHECK-MESSAGES: :[[@LINE-1]]:1: warning: inital value in enum EError has readability issue, explicit initialization of all of enumerators
+  EError_a = 1,
+  EError_b,
+  // CHECK-FIXES: EError_b = 2,
+  EError_c = 3,
+};
+
+enum ENone {
+  ENone_a,
+  ENone_b,
+  eENone_c,
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5chmidti wrote:

The leading `e` was probably a typo, same in the cpp test file.

https://github.com/llvm/llvm-project/pull/86129