From 4d38705f3921dfdf2994b1f6db1f680bd0d927d2 Mon Sep 17 00:00:00 2001
From: Tishj <t_b@live.nl>
Date: Mon, 16 Oct 2023 12:30:51 +0200
Subject: [PATCH 1/2] enable eval_str in python >= 3.10

---
 tools/pythonpkg/src/python_udf.cpp            | 15 +++++++++--
 .../tests/fast/test_string_annotation.py      | 27 +++++++++++++++++++
 2 files changed, 40 insertions(+), 2 deletions(-)
 create mode 100644 tools/pythonpkg/tests/fast/test_string_annotation.py

diff --git a/tools/pythonpkg/src/python_udf.cpp b/tools/pythonpkg/src/python_udf.cpp
index 66ae25e01da2..54494aeb39af 100644
--- a/tools/pythonpkg/src/python_udf.cpp
+++ b/tools/pythonpkg/src/python_udf.cpp
@@ -279,9 +279,20 @@ struct PythonUDFData {
 		}
 	}
 
-	void AnalyzeSignature(const py::object &udf) {
+	py::object GetSignature(const py::object &udf) {
+		const int32_t PYTHON_3_10_HEX = 0x030a00f0;
+		auto python_version = PY_VERSION_HEX;
+
 		auto signature_func = py::module_::import("inspect").attr("signature");
-		auto signature = signature_func(udf);
+		if (python_version >= PYTHON_3_10_HEX) {
+			return signature_func(udf, py::arg("eval_str") = true);
+		} else {
+			return signature_func(udf);
+		}
+	}
+
+	void AnalyzeSignature(const py::object &udf) {
+		auto signature = GetSignature(udf);
 		auto sig_params = signature.attr("parameters");
 		auto return_annotation = signature.attr("return_annotation");
 		if (!py::none().is(return_annotation)) {
diff --git a/tools/pythonpkg/tests/fast/test_string_annotation.py b/tools/pythonpkg/tests/fast/test_string_annotation.py
new file mode 100644
index 000000000000..44de86a27e02
--- /dev/null
+++ b/tools/pythonpkg/tests/fast/test_string_annotation.py
@@ -0,0 +1,27 @@
+import duckdb
+import os
+import pandas as pd
+import pytest
+from typing import Union
+
+# This is used to opt in to PEP 563 (string annotations)
+from __future__ import annotations
+
+
+def make_annotated_function(type):
+    # Create a function that returns its input
+    def test_base(x):
+        return x
+
+    import types
+
+    test_function = types.FunctionType(
+        test_base.__code__, test_base.__globals__, test_base.__name__, test_base.__defaults__, test_base.__closure__
+    )
+    # Add annotations for the return type and 'x'
+    test_function.__annotations__ = {'return': type, 'x': type}
+    return test_function
+
+class TestStringAnnotation(object):
+    def test_string_annotations(self):
+        pass

From 8ce3f48b06327dec40f1ad9a77782af8e03ab4d6 Mon Sep 17 00:00:00 2001
From: Tishj <t_b@live.nl>
Date: Mon, 16 Oct 2023 12:59:43 +0200
Subject: [PATCH 2/2] we cant make use of __future__ annotations feature in
 generated functions - just use strings instead

---
 .../tests/fast/test_string_annotation.py      | 52 ++++++++++++++-----
 1 file changed, 39 insertions(+), 13 deletions(-)

diff --git a/tools/pythonpkg/tests/fast/test_string_annotation.py b/tools/pythonpkg/tests/fast/test_string_annotation.py
index 44de86a27e02..c5500c663ee1 100644
--- a/tools/pythonpkg/tests/fast/test_string_annotation.py
+++ b/tools/pythonpkg/tests/fast/test_string_annotation.py
@@ -1,27 +1,53 @@
 import duckdb
-import os
-import pandas as pd
 import pytest
+import sys
 from typing import Union
 
-# This is used to opt in to PEP 563 (string annotations)
-from __future__ import annotations
 
-
-def make_annotated_function(type):
-    # Create a function that returns its input
-    def test_base(x):
-        return x
+def make_annotated_function(type: str):
+    def test_base():
+        return None
 
     import types
 
     test_function = types.FunctionType(
         test_base.__code__, test_base.__globals__, test_base.__name__, test_base.__defaults__, test_base.__closure__
     )
-    # Add annotations for the return type and 'x'
-    test_function.__annotations__ = {'return': type, 'x': type}
+    # Add the 'type' string as return_annotation
+    test_function.__annotations__ = {'return': type}
     return test_function
 
+
+def python_version_lower_than_3_10():
+    import sys
+
+    if sys.version_info[0] < 3:
+        return True
+    if sys.version_info[1] < 10:
+        return True
+    return False
+
+
 class TestStringAnnotation(object):
-    def test_string_annotations(self):
-        pass
+    @pytest.mark.skipif(
+        python_version_lower_than_3_10(), reason="inspect.signature(eval_str=True) only supported since 3.10 and higher"
+    )
+    @pytest.mark.parametrize(
+        ['input', 'expected'],
+        [
+            ('str', 'VARCHAR'),
+            ('list[str]', 'VARCHAR[]'),
+            ('dict[str, str]', 'MAP(VARCHAR, VARCHAR)'),
+            ('dict[Union[str, bool], str]', 'MAP(UNION(u1 VARCHAR, u2 BOOLEAN), VARCHAR)'),
+        ],
+    )
+    def test_string_annotations(self, duckdb_cursor, input, expected):
+        from inspect import signature
+
+        func = make_annotated_function(input)
+        sig = signature(func)
+        assert sig.return_annotation.__class__ == str
+
+        duckdb_cursor.create_function("foo", func)
+        rel = duckdb_cursor.sql("select foo()")
+        assert rel.types == [expected]