Improved testing

2 files changed, 19 insertions, 0 deletions

diff --git a/src/core/ext/filters/client_channel/subchannel_index.c b/src/core/ext/filters/client_channel/subchannel_index.c
index e291ca9db9..a33ab950bf 100644
--- a/src/core/ext/filters/client_channel/subchannel_index.c
+++ b/src/core/ext/filters/client_channel/subchannel_index.c
@@ -40,6 +40,8 @@ struct grpc_subchannel_key {
 
 GPR_TLS_DECL(subchannel_index_exec_ctx);
 
+static bool g_force_creation = false;
+
 static void enter_ctx(grpc_exec_ctx *exec_ctx) {
   GPR_ASSERT(gpr_tls_get(&subchannel_index_exec_ctx) == 0);
   gpr_tls_set(&subchannel_index_exec_ctx, (intptr_t)exec_ctx);
@@ -84,6 +86,7 @@ static grpc_subchannel_key *subchannel_key_copy(grpc_subchannel_key *k) {
 
 int grpc_subchannel_key_compare(const grpc_subchannel_key *a,
                                 const grpc_subchannel_key *b) {
+  if (g_force_creation) return false;
   int c = GPR_ICMP(a->args.filter_count, b->args.filter_count);
   if (c != 0) return c;
   if (a->args.filter_count > 0) {
@@ -250,3 +253,7 @@ void grpc_subchannel_index_unregister(grpc_exec_ctx *exec_ctx,
 
   leave_ctx(exec_ctx);
 }
+
+void grpc_subchannel_index_test_only_set_force_creation(bool force_creation) {
+  g_force_creation = force_creation;
+}
diff --git a/src/core/ext/filters/client_channel/subchannel_index.h b/src/core/ext/filters/client_channel/subchannel_index.h
index e303bfaa05..98d882a453 100644
--- a/src/core/ext/filters/client_channel/subchannel_index.h
+++ b/src/core/ext/filters/client_channel/subchannel_index.h
@@ -59,4 +59,16 @@ void grpc_subchannel_index_init(void);
 /** Shutdown the subchannel index (global) */
 void grpc_subchannel_index_shutdown(void);
 
+/** \em TEST ONLY.
+ * If \a force_creation is true, all key comparisons will be false, resulting in
+ * new subchannels always being created. Otherwise, the keys will be compared as
+ * usual.
+ *
+ * This function is *not* threadsafe on purpose: it should *only* be used in
+ * test code.
+ *
+ * Tests using this function \em MUST run tests with and without \a
+ * force_creation set. */
+void grpc_subchannel_index_test_only_set_force_creation(bool force_creation);
+
 #endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_SUBCHANNEL_INDEX_H */