esp32: Consolidate check_esp_err functions and add IDF error string.

This commit consolidates a number of check_esp_err functions that check
whether an ESP-IDF return code is OK and raises an exception if not.  The
exception raised is an OSError with the error code as the first argument
(negative if it's ESP-IDF specific) and the ESP-IDF error string as the
second argument.

This commit also fixes esp32.Partition.set_boot to use check_esp_err, and
uses that function for a unit test.

1 files changed, 43 insertions, 0 deletions

diff --git a/tests/esp32/check_err_str.py b/tests/esp32/check_err_str.py
new file mode 100644
index 000000000..055eecf74
--- /dev/null
+++ b/tests/esp32/check_err_str.py
@@ -0,0 +1,43 @@
+try:
+    from esp32 import Partition as p
+    import micropython
+except ImportError:
+    print("SKIP")
+    raise SystemExit
+
+# try some vanilla OSError to get std error code
+try:
+    open("this filedoesnotexist", "r")
+    print("FAILED TO RAISE")
+except OSError as e:
+    print(e)
+
+# try to make nvs partition bootable, which ain't gonna work
+part = p.find(type=p.TYPE_DATA)[0]
+fun = p.set_boot
+try:
+    fun(part)
+    print("FAILED TO RAISE")
+except OSError as e:
+    print(e)
+
+# same but with out of memory condition by locking the heap
+exc = "FAILED TO RAISE"
+micropython.heap_lock()
+try:
+    fun(part)
+except OSError as e:
+    exc = e
+micropython.heap_unlock()
+print("exc:", exc)  # exc empty due to no memory
+
+# same again but having an emergency buffer
+micropython.alloc_emergency_exception_buf(256)
+exc = "FAILED TO RAISE"
+micropython.heap_lock()
+try:
+    fun(part)
+except Exception as e:
+    exc = e
+micropython.heap_unlock()
+print(exc)