1 files changed, 54 insertions, 0 deletions
diff --git a/tests/run/pep557_dataclasses.py b/tests/run/pep557_dataclasses.py
new file mode 100644
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+++ b/tests/run/pep557_dataclasses.py
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+# mode: run
+# tag: pep557, pure3.7
+
+import dataclasses
+from typing import Sequence
+
+
+@dataclasses.dataclass
+class Color:
+    """
+    >>> list(Color.__dataclass_fields__.keys())
+    ['red', 'green', 'blue', 'alpha']
+    >>> Color(1, 2, 3)
+    Color(red=1, green=2, blue=3, alpha=255)
+    >>> Color(1, 2, 3, 4)
+    Color(red=1, green=2, blue=3, alpha=4)
+    >>> Color(green=1, blue=2, red=3, alpha=40)
+    Color(red=3, green=1, blue=2, alpha=40)
+    """
+    red: int
+    green: int
+    blue: int
+    alpha: int = 255
+
+
+@dataclasses.dataclass
+class NamedColor(Color):
+    """
+    >>> list(NamedColor.__dataclass_fields__.keys())
+    ['red', 'green', 'blue', 'alpha', 'names']
+    >>> NamedColor(1, 2, 3)
+    NamedColor(red=1, green=2, blue=3, alpha=255, names=[])
+    >>> NamedColor(1, 2, 3, 4)
+    NamedColor(red=1, green=2, blue=3, alpha=4, names=[])
+    >>> NamedColor(green=1, blue=2, red=3, alpha=40)
+    NamedColor(red=3, green=1, blue=2, alpha=40, names=[])
+    >>> NamedColor(1, 2, 3, names=["blackish", "very dark cyan"])
+    NamedColor(red=1, green=2, blue=3, alpha=255, names=['blackish', 'very dark cyan'])
+    """
+    names: Sequence[str] = dataclasses.field(default_factory=list)
+
+
+@dataclasses.dataclass(frozen=True)
+class IceCream:
+    """
+    >>> IceCream("vanilla")
+    IceCream(flavour='vanilla', num_toppings=2)
+    >>> IceCream("vanilla") == IceCream("vanilla", num_toppings=3)
+    False
+    >>> IceCream("vanilla") == IceCream("vanilla", num_toppings=2)
+    True
+    """
+    flavour: str
+    num_toppings: int = 2