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

Tom de Vries via Gdb-patches
2021-09-11T12:03:32Z

Hi,

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.

Any comments?

Thanks,
- Tom

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

---
gdb/extension.c | 12 +++++++++++
gdb/python/python.c | 62 ++++++++++++++++++++++++++++++++++++++++-------------
2 files changed, 59 insertions(+), 15 deletions(-)

diff --git a/gdb/extension.c b/gdb/extension.c
index 27dce9befa0..3edecb21d6b 100644
--- a/gdb/extension.c
+++ b/gdb/extension.c
@@ -682,6 +682,13 @@ install_gdb_sigint_handler (struct signal_handler *previous)
previous->handler_saved = 0;
}

+#if GDB_SELF_TEST
+namespace selftests {
+extern void (*hook_set_active_ext_lang) (void);
+void (*hook_set_active_ext_lang) (void) = nullptr;
+}
+#endif
+
/* Set the currently active extension language to NOW_ACTIVE.
The result is a pointer to a malloc'd block of memory to pass to
restore_active_ext_lang.
@@ -708,6 +715,11 @@ install_gdb_sigint_handler (struct signal_handler *previous)
struct active_ext_lang_state *
set_active_ext_lang (const struct extension_language_defn *now_active)
{
+#if GDB_SELF_TEST
+ if (selftests::hook_set_active_ext_lang)
+ selftests::hook_set_active_ext_lang ();
+#endif
+
struct active_ext_lang_state *previous
= XCNEW (struct active_ext_lang_state);

diff --git a/gdb/python/python.c b/gdb/python/python.c
index 34c1be76a16..b17b6b69268 100644
--- a/gdb/python/python.c
+++ b/gdb/python/python.c
@@ -1883,6 +1883,14 @@ do_start_initialization ()
#if GDB_SELF_TEST
namespace selftests {

+extern void (*hook_set_active_ext_lang) (void);
+
+static void
+raise_sigint (void)
+{
+ raise (SIGINT);
+}
+
/* Entry point for python unit tests. */

static void
@@ -1897,21 +1905,45 @@ test_python ()
output.clear ();

bool saw_exception = false;
- scoped_restore reset_gdb_python_initialized
- = make_scoped_restore (&gdb_python_initialized, 0);
- try
- {
- CMD (output);
- }
- catch (const gdb_exception &e)
- {
- saw_exception = true;
- SELF_CHECK (e.reason == RETURN_ERROR);
- SELF_CHECK (e.error == GENERIC_ERROR);
- SELF_CHECK (*e.message == "Python not initialized");
- }
- SELF_CHECK (saw_exception);
- SELF_CHECK (output.empty ());
+ {
+ scoped_restore reset_gdb_python_initialized
+ = make_scoped_restore (&gdb_python_initialized, 0);
+ try
+ {
+ CMD (output);
+ }
+ catch (const gdb_exception &e)
+ {
+ saw_exception = true;
+ SELF_CHECK (e.reason == RETURN_ERROR);
+ SELF_CHECK (e.error == GENERIC_ERROR);
+ SELF_CHECK (*e.message == "Python not initialized");
+ }
+ SELF_CHECK (saw_exception);
+ SELF_CHECK (output.empty ());
+ }
+
+ saw_exception = false;
+ {
+ scoped_restore save_hook
+ = make_scoped_restore (&hook_set_active_ext_lang, raise_sigint);
+ try
+ {
+ CMD (output);
+ }
+ catch (const gdb_exception &e)
+ {
+ saw_exception = true;
+ SELF_CHECK (e.reason == RETURN_ERROR);
+ SELF_CHECK (e.error == GENERIC_ERROR);
+ SELF_CHECK (*e.message == "Error while executing Python code.");
+ }
+ SELF_CHECK (saw_exception);
+ std::string ref_output("Traceback (most recent call last):\n"
+ " File \"<string>\", line 1, in <module>\n"
+ "KeyboardInterrupt\n");
+ SELF_CHECK (output == ref_output);
+ }

#undef CMD
}