esp32/modsocket: Fix getaddrinfo to raise on error.

This commit fixes the behaviour of socket.getaddrinfo on the ESP32 so it
raises an OSError when the name resolution fails instead of returning a []
or a resolution for 0.0.0.0.

Tests are added (generic and ESP32-specific) to verify behaviour consistent
with CPython, modulo the different types of exceptions per MicroPython
documentation.

1 files changed, 52 insertions, 0 deletions

diff --git a/tests/net_inet/getaddrinfo.py b/tests/net_inet/getaddrinfo.py
new file mode 100644
index 0000000000..765723ae73
--- /dev/null
+++ b/tests/net_inet/getaddrinfo.py
@@ -0,0 +1,52 @@
+try:
+    import usocket as socket, sys
+except:
+    import socket, sys
+
+
+def test_non_existent():
+    try:
+        res = socket.getaddrinfo("nonexistent.example.com", 80)
+        print("getaddrinfo returned", res)
+    except OSError as e:
+        print("getaddrinfo raised")
+
+
+def test_bogus():
+    try:
+        res = socket.getaddrinfo("hey.!!$$", 80)
+        print("getaddrinfo returned", res)
+    except OSError as e:
+        print("getaddrinfo raised")
+    except Exception as e:
+        print("getaddrinfo raised")  # CPython raises UnicodeError!?
+
+
+def test_ip_addr():
+    try:
+        res = socket.getaddrinfo("10.10.10.10", 80)
+        print("getaddrinfo returned resolutions")
+    except Exception as e:
+        print("getaddrinfo raised", e)
+
+
+def test_0_0_0_0():
+    try:
+        res = socket.getaddrinfo("0.0.0.0", 80)
+        print("getaddrinfo returned resolutions")
+    except Exception as e:
+        print("getaddrinfo raised", e)
+
+
+def test_valid():
+    try:
+        res = socket.getaddrinfo("micropython.org", 80)
+        print("getaddrinfo returned resolutions")
+    except Exception as e:
+        print("getaddrinfo raised", e)
+
+
+test_funs = [n for n in dir() if n.startswith("test_")]
+for f in sorted(test_funs):
+    print("--", f, end=": ")
+    eval(f + "()")