Fixes an Edge Case in jsx-pascal-case

Single letter tag names are techincally PascalCase, and should be
supported.

Author: Daniel Thielman

lib/rules/jsx-pascal-case.js

@@ -9,7 +9,7 @@
 // Constants
 // ------------------------------------------------------------------------------
 
-var PASCAL_CASE_REGEX = /^[A-Z0-9]+[a-z0-9]+(?:[A-Z0-9]+[a-z0-9]*)*$/;
+var PASCAL_CASE_REGEX = /^([A-Z0-9]|[A-Z0-9]+[a-z0-9]+(?:[A-Z0-9]+[a-z0-9]*)*)$/;
 var COMPAT_TAG_REGEX = /^[a-z]|\-/;
 
 // ------------------------------------------------------------------------------

tests/lib/rules/jsx-pascal-case.js

@@ -51,6 +51,10 @@ ruleTester.run('jsx-pascal-case', rule, {
   }, {
     code: '<T3stComp0nent />',
     parserOptions: parserOptions
+  },
+  {
+    code: '<T />',
+    parserOptions: parserOptions
   }],
 
   invalid: [{