[analyzer] Add 'bool ignorePrefix' parameter to cocoa::deriveNamingConvention to control whether
the prefix should be ignored.

E.g. if ignorePrefix is true, "_init" and "init" selectors will both be result in InitRule, but if
ignorePrefix is false, only "init" will return InitRule.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@123262 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/CocoaConventions.cpp b/lib/Analysis/CocoaConventions.cpp
index 2c263ca..4226525 100644
--- a/lib/Analysis/CocoaConventions.cpp
+++ b/lib/Analysis/CocoaConventions.cpp
@@ -54,7 +54,8 @@
   return s;
 }
 
-cocoa::NamingConvention cocoa::deriveNamingConvention(Selector S) {
+cocoa::NamingConvention cocoa::deriveNamingConvention(Selector S,
+                                                      bool ignorePrefix) {
   IdentifierInfo *II = S.getIdentifierInfoForSlot(0);
 
   if (!II)
@@ -62,6 +63,7 @@
 
   const char *s = II->getNameStart();
 
+  const char *orig = s;
   // A method/function name may contain a prefix.  We don't know it is there,
   // however, until we encounter the first '_'.
   while (*s != '\0') {
@@ -73,6 +75,9 @@
     break;
   }
 
+  if (!ignorePrefix && s != orig)
+    return NoConvention;
+
   // Parse the first word, and look for specific keywords.
   const char *wordEnd = parseWord(s);
   assert(wordEnd > s);