chore: Add basic tests for Studio's layer manipulation (#3164)

chore: Add test behaviors for Studio testing

chore: Add basic tests for studio layer adjustment

chore: Fixes from code review

app/module/CMakeLists.txt

@@ -1,4 +1,5 @@
 zephyr_include_directories(include)
 
 add_subdirectory(drivers)
+add_subdirectory(test-behaviors)
 add_subdirectory(lib)

app/module/Kconfig

@@ -1,3 +1,4 @@
 
 rsource "drivers/Kconfig"
-rsource "lib/Kconfig"
+rsource "lib/Kconfig"
+rsource "test-behaviors/Kconfig"

app/module/dts/bindings/test-behaviors/zmk,behavior_add_layer.yaml

@@ -0,0 +1,8 @@
+# Copyright (c) 2025 The ZMK Contributors
+# SPDX-License-Identifier: MIT
+
+description: Layer Adder Behavior
+
+compatible: "zmk,behavior-add-layer"
+
+include: zero_param.yaml

app/module/dts/bindings/test-behaviors/zmk,behavior_move_layer.yaml

@@ -0,0 +1,8 @@
+# Copyright (c) 2025 The ZMK Contributors
+# SPDX-License-Identifier: MIT
+
+description: Layer Mover Behavior
+
+compatible: "zmk,behavior-move-layer"
+
+include: two_param.yaml

app/module/dts/bindings/test-behaviors/zmk,behavior_remove_layer.yaml

@@ -0,0 +1,8 @@
+# Copyright (c) 2025 The ZMK Contributors
+# SPDX-License-Identifier: MIT
+
+description: Layer Remover Behavior
+
+compatible: "zmk,behavior-remove-layer"
+
+include: one_param.yaml

app/module/dts/bindings/test-behaviors/zmk,behavior_set_layer_binding_at_idx.yaml

@@ -0,0 +1,13 @@
+# Copyright (c) 2025 The ZMK Contributors
+# SPDX-License-Identifier: MIT
+
+description: Layer Binding Setter Behavior
+
+compatible: "zmk,behavior-set-layer-binding-at-idx"
+
+include: two_param.yaml
+
+properties:
+  bindings:
+    type: phandle-array
+    required: true

app/module/test-behaviors/CMakeLists.txt

@@ -0,0 +1,6 @@
+if (((NOT CONFIG_ZMK_SPLIT) OR CONFIG_ZMK_SPLIT_ROLE_CENTRAL) AND CONFIG_ZMK_TEST_BEHAVIORS)
+  target_sources(app PRIVATE behavior_add_layer.c)
+  target_sources(app PRIVATE behavior_move_layer.c)
+  target_sources(app PRIVATE behavior_remove_layer.c)
+  target_sources(app PRIVATE behavior_set_layer_binding_at_idx.c)
+endif()

app/module/test-behaviors/Kconfig

@@ -0,0 +1,2 @@
+config ZMK_TEST_BEHAVIORS
+    bool "Include behaviors used for testing purposes"

app/module/test-behaviors/behavior_add_layer.c

@@ -0,0 +1,50 @@
+/*
+ * Copyright (c) 2025 The ZMK Contributors
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#define DT_DRV_COMPAT zmk_behavior_add_layer
+
+#include <zephyr/device.h>
+#include <drivers/behavior.h>
+#include <zephyr/logging/log.h>
+
+#include <zmk/keymap.h>
+#include <zmk/behavior.h>
+
+LOG_MODULE_DECLARE(zmk, CONFIG_ZMK_LOG_LEVEL);
+
+#if (IS_ENABLED(CONFIG_ZMK_KEYMAP_LAYER_REORDERING)) && (DT_HAS_COMPAT_STATUS_OKAY(DT_DRV_COMPAT))
+
+static int on_add_layer_binding_pressed(struct zmk_behavior_binding *binding,
+                                        struct zmk_behavior_binding_event event) {
+    int new_layer = zmk_keymap_add_layer();
+    if (new_layer >= 0) {
+        LOG_DBG("Added layer %d", new_layer);
+        return 0;
+    }
+    switch (new_layer) {
+    case -ENOSPC:
+        LOG_ERR("No more layers can be added. Out of memory.");
+        return -ENOSPC;
+    default:
+        LOG_ERR("Unknown error adding layer: %d", new_layer);
+        return new_layer;
+    }
+}
+
+static int on_add_layer_binding_released(struct zmk_behavior_binding *binding,
+                                         struct zmk_behavior_binding_event event) {
+    return 0;
+}
+
+static const struct behavior_driver_api behavior_add_layer_driver_api = {
+    .binding_pressed = on_add_layer_binding_pressed,
+    .binding_released = on_add_layer_binding_released};
+
+BEHAVIOR_DT_INST_DEFINE(0, NULL, NULL, NULL, NULL, POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEFAULT,
+                        &behavior_add_layer_driver_api);
+
+#endif // IS_ENABLED(CONFIG_ZMK_KEYMAP_LAYER_REORDERING) AND
+       // DT_HAS_COMPAT_STATUS_OKAY(DT_DRV_COMPAT)

app/module/test-behaviors/behavior_move_layer.c

@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2025 The ZMK Contributors
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#define DT_DRV_COMPAT zmk_behavior_move_layer
+
+#include <zephyr/device.h>
+#include <drivers/behavior.h>
+#include <zephyr/logging/log.h>
+
+#include <zmk/keymap.h>
+#include <zmk/behavior.h>
+
+LOG_MODULE_DECLARE(zmk, CONFIG_ZMK_LOG_LEVEL);
+
+#if (IS_ENABLED(CONFIG_ZMK_KEYMAP_LAYER_REORDERING)) && (DT_HAS_COMPAT_STATUS_OKAY(DT_DRV_COMPAT))
+
+static int on_move_layer_binding_pressed(struct zmk_behavior_binding *binding,
+                                         struct zmk_behavior_binding_event event) {
+    int result = zmk_keymap_move_layer(binding->param1, binding->param2);
+
+    if (result < 0) {
+        LOG_ERR("Failed to move layer from index %d to index %d (err: %d)", binding->param1,
+                binding->param2, result);
+        return result;
+    }
+
+    LOG_DBG("Moved layer from index %d to index %d", binding->param1, binding->param2);
+    return 0;
+}
+
+static int on_move_layer_binding_released(struct zmk_behavior_binding *binding,
+                                          struct zmk_behavior_binding_event event) {
+    return 0;
+}
+
+static const struct behavior_driver_api behavior_move_layer_driver_api = {
+    .binding_pressed = on_move_layer_binding_pressed,
+    .binding_released = on_move_layer_binding_released};
+
+BEHAVIOR_DT_INST_DEFINE(0, NULL, NULL, NULL, NULL, POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEFAULT,
+                        &behavior_move_layer_driver_api);
+
+#endif // IS_ENABLED(CONFIG_ZMK_KEYMAP_LAYER_REORDERING) AND
+       // DT_HAS_COMPAT_STATUS_OKAY(DT_DRV_COMPAT)

app/module/test-behaviors/behavior_remove_layer.c

@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2025 The ZMK Contributors
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#define DT_DRV_COMPAT zmk_behavior_remove_layer
+
+#include <zephyr/device.h>
+#include <drivers/behavior.h>
+#include <zephyr/logging/log.h>
+
+#include <zmk/keymap.h>
+#include <zmk/behavior.h>
+
+LOG_MODULE_DECLARE(zmk, CONFIG_ZMK_LOG_LEVEL);
+
+#if (IS_ENABLED(CONFIG_ZMK_KEYMAP_LAYER_REORDERING)) && (DT_HAS_COMPAT_STATUS_OKAY(DT_DRV_COMPAT))
+
+static int on_remove_layer_binding_pressed(struct zmk_behavior_binding *binding,
+                                           struct zmk_behavior_binding_event event) {
+    int result = zmk_keymap_remove_layer(binding->param1);
+    if (result >= 0) {
+        LOG_DBG("Removed layer at index %d", binding->param1);
+        return 0;
+    }
+    switch (result) {
+    case -EINVAL:
+        LOG_ERR("Layer at index %d not found", binding->param1);
+        return -EINVAL;
+    default:
+        LOG_DBG("Unknown error removing layer at index %d: %d", binding->param1, result);
+        return result;
+    }
+}
+
+static int on_remove_layer_binding_released(struct zmk_behavior_binding *binding,
+                                            struct zmk_behavior_binding_event event) {
+    return 0;
+}
+
+static const struct behavior_driver_api behavior_remove_layer_driver_api = {
+    .binding_pressed = on_remove_layer_binding_pressed,
+    .binding_released = on_remove_layer_binding_released};
+
+BEHAVIOR_DT_INST_DEFINE(0, NULL, NULL, NULL, NULL, POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEFAULT,
+                        &behavior_remove_layer_driver_api);
+#endif // IS_ENABLED(CONFIG_ZMK_KEYMAP_LAYER_REORDERING) AND
+       // DT_HAS_COMPAT_STATUS_OKAY(DT_DRV_COMPAT)

app/module/test-behaviors/behavior_set_layer_binding_at_idx.c

@@ -0,0 +1,100 @@
+/*
+ * Copyright (c) 2025 The ZMK Contributors
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#define DT_DRV_COMPAT zmk_behavior_set_layer_binding_at_idx
+
+#include <zephyr/device.h>
+#include <drivers/behavior.h>
+#include <zephyr/logging/log.h>
+
+#include <zmk/keymap.h>
+#include <zmk/behavior.h>
+
+LOG_MODULE_DECLARE(zmk, CONFIG_ZMK_LOG_LEVEL);
+
+#if DT_HAS_COMPAT_STATUS_OKAY(DT_DRV_COMPAT)
+
+struct behavior_set_layer_binding_at_idx_config {
+    size_t bindings_len;
+    struct zmk_behavior_binding *bindings;
+};
+
+struct behavior_set_layer_binding_at_idx_data {
+    size_t current_idx;
+};
+
+static int on_set_layer_binding_at_idx_binding_pressed(struct zmk_behavior_binding *binding,
+                                                       struct zmk_behavior_binding_event event) {
+    const struct device *dev = zmk_behavior_get_binding(binding->behavior_dev);
+    const struct behavior_set_layer_binding_at_idx_config *cfg = dev->config;
+    struct behavior_set_layer_binding_at_idx_data *data = dev->data;
+
+    if (cfg->bindings_len == 0) {
+        LOG_ERR("No bindings configured");
+        return -EINVAL;
+    }
+
+    struct zmk_behavior_binding *binding_to_set = &cfg->bindings[data->current_idx];
+
+    int result =
+        zmk_keymap_set_layer_binding_at_idx(binding->param1, binding->param2, *binding_to_set);
+
+    if (result < 0) {
+        LOG_ERR("Failed to set binding at layer %d, index %d (err: %d)", binding->param1,
+                binding->param2, result);
+        return result;
+    }
+
+    LOG_DBG("Set binding at layer %d, index %d to binding %zu/%zu", binding->param1,
+            binding->param2, data->current_idx + 1, cfg->bindings_len);
+
+    // Move to next binding, wrap around if at end
+    data->current_idx = (data->current_idx + 1) % cfg->bindings_len;
+
+    return 0;
+}
+
+static int on_set_layer_binding_at_idx_binding_released(struct zmk_behavior_binding *binding,
+                                                        struct zmk_behavior_binding_event event) {
+    return 0;
+}
+
+static const struct behavior_driver_api behavior_set_layer_binding_at_idx_driver_api = {
+    .binding_pressed = on_set_layer_binding_at_idx_binding_pressed,
+    .binding_released = on_set_layer_binding_at_idx_binding_released};
+
+static int behavior_set_layer_binding_at_idx_init(const struct device *dev) {
+    struct behavior_set_layer_binding_at_idx_data *data = dev->data;
+    data->current_idx = 0;
+    return 0;
+};
+
+#define _TRANSFORM_ENTRY(idx, node) ZMK_KEYMAP_EXTRACT_BINDING(idx, node)
+
+#define TRANSFORMED_BINDINGS(node)                                                                 \
+    {LISTIFY(DT_INST_PROP_LEN(node, bindings), _TRANSFORM_ENTRY, (, ), DT_DRV_INST(node))}
+
+#define SET_LAYER_BINDING_AT_IDX_INST(n)                                                           \
+    static struct behavior_set_layer_binding_at_idx_data                                           \
+        behavior_set_layer_binding_at_idx_data_##n = {};                                           \
+                                                                                                   \
+    static const struct zmk_behavior_binding                                                       \
+        behavior_set_layer_binding_at_idx_config_##n##_bindings[DT_INST_PROP_LEN(n, bindings)] =   \
+            TRANSFORMED_BINDINGS(n);                                                               \
+    static const struct behavior_set_layer_binding_at_idx_config                                   \
+        behavior_set_layer_binding_at_idx_config_##n = {                                           \
+            .bindings_len = DT_INST_PROP_LEN(n, bindings),                                         \
+            .bindings = behavior_set_layer_binding_at_idx_config_##n##_bindings};                  \
+                                                                                                   \
+    BEHAVIOR_DT_INST_DEFINE(n, behavior_set_layer_binding_at_idx_init, NULL,                       \
+                            &behavior_set_layer_binding_at_idx_data_##n,                           \
+                            &behavior_set_layer_binding_at_idx_config_##n, POST_KERNEL,            \
+                            CONFIG_KERNEL_INIT_PRIORITY_DEFAULT,                                   \
+                            &behavior_set_layer_binding_at_idx_driver_api);
+
+DT_INST_FOREACH_STATUS_OKAY(SET_LAYER_BINDING_AT_IDX_INST)
+
+#endif // DT_HAS_COMPAT_STATUS_OKAY(DT_DRV_COMPAT)