fix(uart): enlarged task stack size for uart_async_rxtxtasks example

Meanwhile, added CI pytest for some UART examples

Closes https://github.com/espressif/esp-idf/issues/15363

examples/peripherals/uart/uart_async_rxtxtasks/main/Kconfig.projbuild

@@ -0,0 +1,35 @@
+menu "Example Configuration"
+
+    orsource "$IDF_PATH/examples/common_components/env_caps/$IDF_TARGET/Kconfig.env_caps"
+
+    config EXAMPLE_UART_BAUD_RATE
+        int "UART communication speed"
+        range 1200 115200
+        default 115200
+        help
+            UART communication speed for the example.
+
+    config EXAMPLE_UART_RXD
+        int "UART RXD pin number"
+        range ENV_GPIO_RANGE_MIN ENV_GPIO_IN_RANGE_MAX
+        default 5
+        help
+            GPIO number for UART RX pin. See UART documentation for more information
+            about available pin numbers for UART.
+
+    config EXAMPLE_UART_TXD
+        int "UART TXD pin number"
+        range ENV_GPIO_RANGE_MIN ENV_GPIO_OUT_RANGE_MAX
+        default 4
+        help
+            GPIO number for UART TX pin. See UART documentation for more information
+            about available pin numbers for UART.
+
+    config EXAMPLE_TASK_STACK_SIZE
+        int "Example task stack size"
+        range 1024 16384
+        default 3072
+        help
+            Defines stack size for UART TX and RX tasks. Insufficient stack size can cause crash.
+
+endmenu

examples/peripherals/uart/uart_async_rxtxtasks/main/uart_async_rxtxtasks_main.c

@@ -16,13 +16,13 @@
 
 static const int RX_BUF_SIZE = 1024;
 
-#define TXD_PIN (GPIO_NUM_4)
+#define TXD_PIN (CONFIG_EXAMPLE_UART_TXD)
-#define RXD_PIN (GPIO_NUM_5)
+#define RXD_PIN (CONFIG_EXAMPLE_UART_RXD)
 
 void init(void)
 {
     const uart_config_t uart_config = {
-        .baud_rate = 115200,
+        .baud_rate = CONFIG_EXAMPLE_UART_BAUD_RATE,
         .data_bits = UART_DATA_8_BITS,
         .parity = UART_PARITY_DISABLE,
         .stop_bits = UART_STOP_BITS_1,
@@ -72,6 +72,6 @@ static void rx_task(void *arg)
 void app_main(void)
 {
     init();
-    xTaskCreate(rx_task, "uart_rx_task", 1024 * 2, NULL, configMAX_PRIORITIES - 1, NULL);
+    xTaskCreate(rx_task, "uart_rx_task", CONFIG_EXAMPLE_TASK_STACK_SIZE, NULL, configMAX_PRIORITIES - 1, NULL);
-    xTaskCreate(tx_task, "uart_tx_task", 1024 * 2, NULL, configMAX_PRIORITIES - 2, NULL);
+    xTaskCreate(tx_task, "uart_tx_task", CONFIG_EXAMPLE_TASK_STACK_SIZE, NULL, configMAX_PRIORITIES - 2, NULL);
 }

examples/peripherals/uart/uart_async_rxtxtasks/pytest_async_rxtxtasks.py

@@ -0,0 +1,10 @@
+# SPDX-FileCopyrightText: 2025 Espressif Systems (Shanghai) CO LTD
+# SPDX-License-Identifier: CC0-1.0
+import pytest
+from pytest_embedded import Dut
+
+
+@pytest.mark.supported_targets
+@pytest.mark.generic
+def test_uart_async_rxtxtasks_example(dut: Dut) -> None:
+    dut.expect_exact('TX_TASK: Wrote 11 bytes')

examples/peripherals/uart/uart_events/pytest_events.py

@@ -0,0 +1,14 @@
+# SPDX-FileCopyrightText: 2025 Espressif Systems (Shanghai) CO LTD
+# SPDX-License-Identifier: CC0-1.0
+import pytest
+from pytest_embedded import Dut
+
+
+@pytest.mark.supported_targets
+@pytest.mark.generic
+def test_uart_events_example(dut: Dut) -> None:
+    dut.expect_exact('Returned from app_main()')
+    dut.write('a')
+    dut.expect_exact('uart_events: [UART DATA]: 2')  # dut.write will add an extra '\n'
+    dut.write('HA')
+    dut.expect_exact('uart_events: [UART DATA]: 3')  # dut.write will add an extra '\n'

examples/peripherals/uart/uart_select/pytest_uart_select.py

@@ -0,0 +1,12 @@
+# SPDX-FileCopyrightText: 2025 Espressif Systems (Shanghai) CO LTD
+# SPDX-License-Identifier: CC0-1.0
+import pytest
+from pytest_embedded import Dut
+
+
+@pytest.mark.supported_targets
+@pytest.mark.generic
+def test_uart_select_example(dut: Dut) -> None:
+    dut.expect_exact('uart_select_example: Timeout has been reached and nothing has been received')
+    dut.write('a')
+    dut.expect_exact('uart_select_example: Received: a')