bpo-33502: dataclass._Dataclassparams repr: use repr of each member. (GH-6812)

(cherry picked from commit 3059042410)

Co-authored-by: Eric V. Smith <ericvsmith@users.noreply.github.com>

Lib/dataclasses.py

@@ -274,12 +274,12 @@ class _DataclassParams:
 
     def __repr__(self):
         return ('_DataclassParams('
-                f'init={self.init},'
-                f'repr={self.repr},'
-                f'eq={self.eq},'
-                f'order={self.order},'
-                f'unsafe_hash={self.unsafe_hash},'
-                f'frozen={self.frozen}'
+                f'init={self.init!r},'
+                f'repr={self.repr!r},'
+                f'eq={self.eq!r},'
+                f'order={self.order!r},'
+                f'unsafe_hash={self.unsafe_hash!r},'
+                f'frozen={self.frozen!r}'
                 ')')
 
 

f.py

@@ -0,0 +1,12 @@
+from __future__ import annotations
+from dataclasses import dataclass
+from typing import List
+from typing import ClassVar as CV
+
+@dataclass
+class A:
+    a: List[str]
+
+@dataclass
+class B(A):
+    b: CV[int]

j.py

@@ -0,0 +1,15 @@
+
+class X:
+    def __init__(self, value):
+        self.value = value
+    def __str__(self):
+        return str(self.value)
+    def __format__(self, fmt):
+        assert fmt[0] == '='
+        self.value = eval(fmt[1:])
+        return ''
+
+x = X(3)
+print(x)
+f'{x:=4}'   # Behold!
+print(x)

t.py

@@ -0,0 +1,20 @@
+from dataclasses import *
+
+class D:
+    """A descriptor class that knows its name."""
+    def __set_name__(self, owner, name):
+        self.name = name
+    def __get__(self, instance, owner):
+        if instance is not None:
+            return 1
+        return self
+
+from dataclasses import *
+
+@dataclass
+class C:
+    d: int = field(default=D(), init=False)
+
+@dataclass
+class E(C):
+    e: int = field(default=D(), init=False)

x.py

@@ -0,0 +1,31 @@
+#from __future__ import annotations
+from typing import ClassVar, Dict, get_type_hints
+from dataclasses import *
+
+class Starship:
+    stats: ClassVar[Dict[str, int]] = {}
+
+#print(get_type_hints(Starship))
+
+#class A:
+#    a: Dict[int, C]
+
+#print(get_type_hints(A))
+
+cv = [ClassVar[int]]
+
+@dataclass
+class C:
+    CVS = [ClassVar[str]]
+    a: cv[0]
+    b: 'C'
+    c: 'CVS[0]'
+    x: 'ClassVar["int"]'
+    y: 'ClassVar[C]'
+
+print()
+print(C.__annotations__)
+print(C.__dataclass_fields__)
+
+
+#print(get_type_hints(C))