Bug 551286: Add a per function 'final' keyword in C++. r=tglek

xpcom/analysis/final.js

@@ -7,6 +7,30 @@ function process_type(c)
   }
 }
 
+function process_function(decl, body)
+{
+  if (!decl.memberOf)
+    return;
+
+  let c = decl.memberOf;
+  if ((c.kind == 'class' || c.kind == 'struct') && !c.isIncomplete) {
+    for each (let base in ancestorTypes(c))
+      for each (let member in base.members)
+        if (member.isFunction && isFinal(member) && member.shortName == decl.shortName)
+          error("Function '" + decl.name + "' overrides final ancestor in '" +
+                base.name + "'.", c.loc);
+  }
+}
+
+function ancestorTypes(c)
+{
+  for each (let base in c.bases) {
+    yield base.type;
+    for (let bb in ancestorTypes(base.type))
+      yield bb;
+  }
+}
+
 function isFinal(c)
 {
   if (c.isIncomplete)

xpcom/tests/static-checker/Makefile.in

@@ -49,6 +49,8 @@ include $(DEPTH)/config/autoconf.mk
 FINAL_FAILURE_TESTCASES = \
   TestFinal.cpp \
   TestFinalTemplate.cpp \
+  TestFinalFunction.cpp \
+  TestFinalGrandparentFunction.cpp \
   $(NULL)
 
 STACK_FAILURE_TESTCASES = \

xpcom/tests/static-checker/TestFinalFunction.cpp

@@ -0,0 +1,9 @@
+#include "nscore.h"
+
+class Base {
+  virtual void NS_FINAL final() {}
+};
+
+class Derived : public Base {
+  virtual void final() {}
+};

xpcom/tests/static-checker/TestFinalGrandparentFunction.cpp

@@ -0,0 +1,12 @@
+#include "nscore.h"
+
+class Base {
+  virtual void NS_FINAL final() {}
+};
+
+class Derived : public Base {
+};
+
+class VeryDerived : public Derived {
+  void final() {}
+};