Fix #10652: FP: misra-c2012-10.4 (char)'1' != (char) (#5556)

Author: swasti16

addons/misra.py

@@ -495,6 +495,13 @@ def getEssentialTypeCategory(expr):
             return 'char'
         return expr.valueType.sign
 
+    if (expr.isCast and expr.str == "("):
+        castTok = expr.next
+        while castTok.isName or castTok.str == "*":
+            if castTok.str == 'char' and not castTok.isSigned and not castTok.isUnsigned:
+                return 'char'
+            castTok = castTok.next
+
     if expr.valueType:
         return expr.valueType.sign
     return None

addons/test/misra/misra-test.c

@@ -724,6 +724,12 @@ static void misra_10_4(u32 x, s32 y) {
   if ('\0' == cmd.buf[0]) //no-warning
   {
   }
+
+  // #10652
+  char c;
+  if ((char)'1' == c) {}            // no warning
+  if ((unsigned char)'1' == c) {}   //10.4
+  if ((signed char)'1' == c) {}     //10.4
 }
 
 static void misra_10_5(uint16_t x) {