fix: add PEP 563 support, see #43

dataconf/main.py

@@ -1,3 +1,4 @@
+import inspect
 import os
 from typing import List
 
@@ -9,11 +10,41 @@
 import pyparsing
 
 
+def inject_callee_scope(func):
+    def inner(*args, **kwargs):
+        noglobals = "globalns" not in kwargs
+        nolocals = "localns" not in kwargs
+
+        if noglobals or nolocals:
+            frame = inspect.stack()[1][0]
+
+            if noglobals:
+                kwargs["globalns"] = frame.f_globals
+            if nolocals:
+                kwargs["localns"] = frame.f_locals
+
+        return func(
+            *args,
+            **kwargs,
+        )
+
+    return inner
+
+
+@inject_callee_scope
 def parse(
-    conf: ConfigTree, clazz, strict: bool = True, ignore_unexpected: bool = False
+    conf: ConfigTree,
+    clazz,
+    strict: bool = True,
+    ignore_unexpected: bool = False,
+    globalns=None,
+    localns=None,
 ):
+
     try:
-        return utils.__parse(conf, clazz, "", strict, ignore_unexpected)
+        return utils.__parse(
+            conf, clazz, "", strict, ignore_unexpected, globalns, localns
+        )
     except pyparsing.ParseSyntaxException as e:
         raise MalformedConfigException(
             f'parsing failure line {e.lineno} character {e.col}, got "{e.line}"'
@@ -50,42 +81,52 @@ def file(self, path: str, **kwargs) -> "Multi":
         conf = ConfigFactory.parse_file(path)
         return Multi(self.confs + [conf], self.strict, **kwargs)
 
-    def on(self, clazz):
+    @inject_callee_scope
+    def on(self, clazz, globalns=None, localns=None):
         conf, *nxts = self.confs
         for nxt in nxts:
             conf = ConfigTree.merge_configs(conf, nxt)
-        return parse(conf, clazz, self.strict, **self.kwargs)
+        return parse(
+            conf, clazz, self.strict, globalns=globalns, localns=localns, **self.kwargs
+        )
 
 
 multi = Multi([])
 
 
-def env(prefix: str, clazz, **kwargs):
-    return multi.env(prefix, **kwargs).on(clazz)
+@inject_callee_scope
+def env(prefix: str, clazz, globalns=None, localns=None, **kwargs):
+    return multi.env(prefix, **kwargs).on(clazz, globalns=globalns, localns=localns)
 
 
-def dict(obj: str, clazz, **kwargs):
-    return multi.dict(obj, **kwargs).on(clazz)
+@inject_callee_scope
+def dict(obj: str, clazz, globalns=None, localns=None, **kwargs):
+    return multi.dict(obj, **kwargs).on(clazz, globalns=globalns, localns=localns)
 
 
-def string(s: str, clazz, **kwargs):
-    return multi.string(s, **kwargs).on(clazz)
+@inject_callee_scope
+def string(s: str, clazz, globalns=None, localns=None, **kwargs):
+    return multi.string(s, **kwargs).on(clazz, globalns=globalns, localns=localns)
 
 
-def url(uri: str, clazz, **kwargs):
-    return multi.url(uri, **kwargs).on(clazz)
+@inject_callee_scope
+def url(uri: str, clazz, globalns=None, localns=None, **kwargs):
+    return multi.url(uri, **kwargs).on(clazz, globalns=globalns, localns=localns)
 
 
-def file(path: str, clazz, **kwargs):
-    return multi.file(path, **kwargs).on(clazz)
+@inject_callee_scope
+def file(path: str, clazz, globalns=None, localns=None, **kwargs):
+    return multi.file(path, **kwargs).on(clazz, globalns=globalns, localns=localns)
 
 
-def load(path: str, clazz, **kwargs):
-    return file(path, clazz, **kwargs)
+@inject_callee_scope
+def load(path: str, clazz, globalns=None, localns=None, **kwargs):
+    return file(path, clazz, globalns=globalns, localns=localns, **kwargs)
 
 
-def loads(s: str, clazz, **kwargs):
-    return string(s, clazz, **kwargs)
+@inject_callee_scope
+def loads(s: str, clazz, globalns=None, localns=None, **kwargs):
+    return string(s, clazz, globalns=globalns, localns=localns, **kwargs)
 
 
 def dump(file: str, instance: object, out: str):

dataconf/utils.py

@@ -5,6 +5,7 @@
 from datetime import datetime
 from typing import get_args
 from typing import get_origin
+from typing import get_type_hints
 from typing import Union
 
 from dataconf.exceptions import EnvListOrderException
@@ -39,7 +40,7 @@ def is_optional(type):
     return get_origin(type) is Union and NoneType in get_args(type)
 
 
-def __parse(value: any, clazz, path, strict, ignore_unexpected):
+def __parse(value: any, clazz, path, strict, ignore_unexpected, globalns, localns):
 
     if is_dataclass(clazz):
 
@@ -51,6 +52,7 @@ def __parse(value: any, clazz, path, strict, ignore_unexpected):
         fs = {}
         renamings = dict()
 
+        type_hints = get_type_hints(clazz, globalns, localns)
         for f in fields(clazz):
 
             if f.name in value:
@@ -66,10 +68,16 @@ def __parse(value: any, clazz, path, strict, ignore_unexpected):
 
             if not isinstance(val, _MISSING_TYPE):
                 fs[f.name] = __parse(
-                    val, f.type, f"{path}.{f.name}", strict, ignore_unexpected
+                    val,
+                    type_hints[f.name],
+                    f"{path}.{f.name}",
+                    strict,
+                    ignore_unexpected,
+                    globalns,
+                    localns,
                 )
 
-            elif is_optional(f.type):
+            elif is_optional(type_hints[f.name]):
                 # Optional not found
                 fs[f.name] = None
 
@@ -94,7 +102,15 @@ def __parse(value: any, clazz, path, strict, ignore_unexpected):
             raise MissingTypeException("expected list with type information: List[?]")
         if value is not None:
             return [
-                __parse(v, args[0], f"{path}[]", strict, ignore_unexpected)
+                __parse(
+                    v,
+                    args[0],
+                    f"{path}[]",
+                    strict,
+                    ignore_unexpected,
+                    globalns,
+                    localns,
+                )
                 for v in value
             ]
         return None
@@ -106,7 +122,15 @@ def __parse(value: any, clazz, path, strict, ignore_unexpected):
             )
         if value is not None:
             return {
-                k: __parse(v, args[1], f"{path}.{k}", strict, ignore_unexpected)
+                k: __parse(
+                    v,
+                    args[1],
+                    f"{path}.{k}",
+                    strict,
+                    ignore_unexpected,
+                    globalns,
+                    localns,
+                )
                 for k, v in value.items()
             }
         return None
@@ -120,6 +144,8 @@ def __parse(value: any, clazz, path, strict, ignore_unexpected):
                 path,
                 strict,
                 ignore_unexpected,
+                globalns,
+                localns,
             )
         except TypeConfigException:
             # cannot parse Optional
@@ -129,10 +155,14 @@ def __parse(value: any, clazz, path, strict, ignore_unexpected):
         left, right = args
 
         try:
-            return __parse(value, left, path, strict, ignore_unexpected)
+            return __parse(
+                value, left, path, strict, ignore_unexpected, globalns, localns
+            )
         except TypeConfigException as left_failure:
             try:
-                return __parse(value, right, path, strict, ignore_unexpected)
+                return __parse(
+                    value, right, path, strict, ignore_unexpected, globalns, localns
+                )
             except TypeConfigException as right_failure:
                 raise TypeConfigException(
                     f"expected type {clazz} at {path}, failed both:\n- {left_failure}\n- {right_failure}"
@@ -186,7 +216,15 @@ def __parse(value: any, clazz, path, strict, ignore_unexpected):
     for child_clazz in sorted(clazz.__subclasses__(), key=lambda c: c.__name__):
         if is_dataclass(child_clazz):
             try:
-                return __parse(value, child_clazz, path, strict, ignore_unexpected)
+                return __parse(
+                    value,
+                    child_clazz,
+                    path,
+                    strict,
+                    ignore_unexpected,
+                    globalns,
+                    localns,
+                )
             except (
                 TypeConfigException,
                 MalformedConfigException,

tests/test_futur_annotations.py

@@ -0,0 +1,35 @@
+from __future__ import annotations
+
+from dataclasses import dataclass
+import os
+from typing import get_type_hints
+from typing import Text
+
+import dataconf
+from dataconf.main import inject_callee_scope
+
+
+@inject_callee_scope
+def out_of_scope_assert(clazz, expected, globalns, localns):
+    assert get_type_hints(clazz, globalns, localns)["a"] is expected
+
+
+class TestFuturAnnotations:
+    def test_43(self) -> None:
+        @dataclass
+        class Model:
+            token: str
+
+        os.environ["TEST_token"] = "1"
+        dataconf.env("TEST_", Model)
+
+    def test_repro(self) -> None:
+        @dataclass
+        class A:
+            value: Text
+
+        @dataclass
+        class B:
+            a: A
+
+        out_of_scope_assert(B, A, globalns={})