Enable call of overloaded subscript operator from python

If you try to use the overloaded subscript operator of a class
in python, it fails like this:

(gdb) py print(gdb.parse_and_eval('b')[5])
Traceback (most recent call last):
  File "<string>", line 1, in <module>
gdb.error: Cannot subscript requested type.
Error while executing Python code.

This simply checks if such an operator exists, and calls it
instead, making this possible:

(gdb) py print(gdb.parse_and_eval('b')[5])
102 'f'

Approved-By: Tom Tromey <tom@tromey.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/gdb/testsuite/gdb.python/py-value-cc.cc b/gdb/testsuite/gdb.python/py-value-cc.cc
index 2d38a26..08b9915 100644
--- a/gdb/testsuite/gdb.python/py-value-cc.cc
+++ b/gdb/testsuite/gdb.python/py-value-cc.cc
@@ -42,6 +42,7 @@ class B : public A {
   int arg0_func ();
   int arg1_func (int arg1);
   int arg2_func (int arg1, int arg2);
+  char operator[] (int num);
 };
 
 int B::static_func ()
@@ -64,6 +65,11 @@ int B::arg2_func (int arg1, int arg2)
   return a * arg1 + arg2;
 }
 
+char B::operator[] (int num)
+{
+  return a + num;
+}
+
 struct X
 {
   union { int x; char y; };