Fix hg showconfig traceback with values that aren't strings

mercurial/ui.py

@@ -309,7 +309,7 b' class ui(object):'
         sections.sort()
         for section in sections:
             for name, value in self.configitems(section, untrusted):
-                yield section, name, value.replace('\n', '\\n')
+                yield section, name, str(value).replace('\n', '\\n')
 
     def extensions(self):
         result = self.configitems("extensions")

tests/test-hook

@@ -203,4 +203,6 b" hg ci -m 'add foo'"
 echo >> foo
 hg ci --debug -m 'change foo' | sed -e 's/ at .*>/>/'
 
+hg showconfig hooks | sed -e 's/ at .*>/>/'
+
 exit 0

tests/test-hook.out

@@ -142,3 +142,4 b' Automatically installed hook'
 foo
 calling hook commit.auto: <function autohook>
 Automatically installed hook
+hooks.commit.auto=<function autohook>