[gdb/testsuite] Reimplement gdb.gdb/python-interrupts.exp as unittest

The test-case gdb.gdb/python-interrupts.exp:
- runs to captured_command_loop
- sets a breakpoint at set_active_ext_lang
- calls a python command
- verifies the command triggers the breakpoint
- sends a signal and verifies the result

The test-case is fragile, because (f.i. with -flto) it cannot be guaranteed
that captured_command_loop and set_active_ext_lang are available for setting
breakpoints.

Reimplement the test-case as unittest, using:
- execute_command_to_string to capture the output
- try/catch to catch the "Error while executing Python code" exception
- a new hook selftests::hook_set_active_ext_lang to raise the signal

Tested on x86_64-linux.

1 files changed, 6 insertions, 0 deletions

diff --git a/gdb/extension.h b/gdb/extension.h
index 56f57560de3..2f2ca3e7743 100644
--- a/gdb/extension.h
+++ b/gdb/extension.h
@@ -319,4 +319,10 @@ extern void get_matching_xmethod_workers
 extern gdb::optional<std::string> ext_lang_colorize
   (const std::string &filename, const std::string &contents);
 
+#if GDB_SELF_TEST
+namespace selftests {
+extern void (*hook_set_active_ext_lang) ();
+}
+#endif
+
 #endif /* EXTENSION_H */