test: complete tx coverage and use canard user_context

Author: pavel-kirienko

libcanard/canard.h

@@ -470,6 +470,8 @@ struct canard_t
     uint_least8_t         p2p_transfer_id[CANARD_NODE_ID_CAPACITY];
 
     const canard_vtable_t* vtable;
+
+    void* user_context;
 };
 
 /// The TX queue is shared between all redundant interfaces with deduplication (each frame is enqueued only once).

tests/src/test_api_tx.cpp

@@ -1,20 +1,67 @@
 // This software is distributed under the terms of the MIT License.
 // Copyright (c) OpenCyphal Development Team.
 
-#include <canard.h>
+#include "helpers.h"
 #include <unity.h>
 #include <cstdint>
 #include <cstdlib>
 #include <memory>
 
+// Simple allocator that always fails.
+static void* dummy_alloc_mem(const canard_mem_t mem, const size_t size) { return dummy_alloc(mem.context, size); }
+static void  dummy_free_mem(const canard_mem_t mem, const size_t size, void* const pointer)
+{
+    dummy_free(mem.context, size, pointer);
+}
+
+static void test_canard_publish_validation(void)
+{
+    canard_t self = {};
+
+    // Invalid interface bitmap.
+    const canard_bytes_chain_t payload = { .bytes = { .size = 0, .data = NULL }, .next = NULL };
+    TEST_ASSERT_FALSE(canard_publish(&self, 0, 0, canard_prio_nominal, 0, 0, payload, CANARD_USER_CONTEXT_NULL, false));
+
+    // Invalid payload.
+    const canard_bytes_chain_t bad_payload = { .bytes = { .size = 1, .data = NULL }, .next = NULL };
+    TEST_ASSERT_FALSE(
+      canard_publish(&self, 0, 1, canard_prio_nominal, 0, 0, bad_payload, CANARD_USER_CONTEXT_NULL, false));
+}
+
+static void test_canard_publish_oom(void)
+{
+    canard_mem_vtable_t vtable = {};
+    vtable.free                = dummy_free_mem;
+    vtable.alloc               = dummy_alloc_mem;
+    canard_t self              = {};
+    self.mem.tx_transfer       = canard_mem_t{ &vtable, NULL };
+    self.mem.tx_frame          = canard_mem_t{ &vtable, NULL };
+
+    // Allocation failure in txfer_new should return false.
+    const canard_bytes_chain_t payload = { .bytes = { .size = 0, .data = NULL }, .next = NULL };
+    TEST_ASSERT_FALSE(canard_publish(&self, 0, 1, canard_prio_nominal, 0, 0, payload, CANARD_USER_CONTEXT_NULL, false));
+}
+
+static void test_canard_0v1_publish_requires_node_id(void)
+{
+    canard_t self = {};
+
+    // Node-ID zero should reject the request.
+    const canard_bytes_chain_t payload = { .bytes = { .size = 0, .data = NULL }, .next = NULL };
+    TEST_ASSERT_FALSE(canard_0v1_publish(&self, 0, 1, canard_prio_nominal, 1, 0xFFFF, 0, payload));
+}
+
 extern "C" void setUp() {}
 extern "C" void tearDown() {}
 
 int main()
 {
     UNITY_BEGIN();
 
-    // TODO add tests
+    // canard_publish/canard_0v1_publish validation.
+    RUN_TEST(test_canard_publish_validation);
+    RUN_TEST(test_canard_publish_oom);
+    RUN_TEST(test_canard_0v1_publish_requires_node_id);
 
     return UNITY_END();
 }