tests/qtest/migration: Add a wrapper to print test names

Our usage of gtest results in us losing the very basic functionality
of "knowing which test failed". The issue is that gtest only prints
test names ("paths" in gtest parlance) once the test has finished, but
we use asserts in the tests and crash gtest itself before it can print
anything. We also use a final abort when the result of g_test_run is
not 0.

Depending on how the test failed/broke we can see the function that
trigged the abort, which may be representative of the test, but it
could also just be some generic function.

We have been relying on the primitive method of looking at the name of
the previous successful test and then looking at the code to figure
out which test should have come next.

Add a wrapper to the test registration that does the job of printing
the test name before running.

Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/20240104142144.9680-7-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>

tests/qtest/migration-helpers.c

@@ -291,3 +291,35 @@ char *resolve_machine_version(const char *alias, const char *var1,
 
     return find_common_machine_version(machine_name, var1, var2);
 }
+
+typedef struct {
+    char *name;
+    void (*func)(void);
+} MigrationTest;
+
+static void migration_test_destroy(gpointer data)
+{
+    MigrationTest *test = (MigrationTest *)data;
+
+    g_free(test->name);
+    g_free(test);
+}
+
+static void migration_test_wrapper(const void *data)
+{
+    MigrationTest *test = (MigrationTest *)data;
+
+    g_test_message("Running /%s%s", qtest_get_arch(), test->name);
+    test->func();
+}
+
+void migration_test_add(const char *path, void (*fn)(void))
+{
+    MigrationTest *test = g_new0(MigrationTest, 1);
+
+    test->func = fn;
+    test->name = g_strdup(path);
+
+    qtest_add_data_func_full(path, test, migration_test_wrapper,
+                             migration_test_destroy);
+}

tests/qtest/migration-helpers.h

@@ -52,4 +52,5 @@ char *find_common_machine_version(const char *mtype, const char *var1,
                                   const char *var2);
 char *resolve_machine_version(const char *alias, const char *var1,
                               const char *var2);
+void migration_test_add(const char *path, void (*fn)(void));
 #endif /* MIGRATION_HELPERS_H */