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AlexWaygoodAlexWaygood
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Clarify ClassVar protocol conformance expectations
1 parent 6f7fa73 commit b297a5f

9 files changed

Lines changed: 62 additions & 6 deletions

‎conformance/results/mypy/protocols_definition.toml‎

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@@ -51,6 +51,9 @@ protocols_definition.py:340: error: Incompatible types in assignment (expression
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protocols_definition.py:340: note: Protocol member Template6.val1 expected settable variable, got read-only attribute
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protocols_definition.py:341: error: Incompatible types in assignment (expression has type "Concrete6_Bad3", variable has type "Template6") [assignment]
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protocols_definition.py:341: note: Protocol member Template6.val1 expected settable variable, got read-only attribute
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protocols_definition.py:369: error: Incompatible types in assignment (expression has type "Concrete7_Bad1", variable has type "Template7") [assignment]
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protocols_definition.py:369: note: Protocol member Template7.val1 expected class variable, got instance variable
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protocols_definition.py:370: error: Incompatible types in assignment (expression has type "Concrete7_Bad2", variable has type "Template7") [assignment]
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"""
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conformance_automated = "Fail"
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errors_diff = """

‎conformance/results/pycroscope/protocols_definition.toml‎

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@@ -1,5 +1,10 @@
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conformance_automated = "Pass"
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conformance_automated = "Fail"
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conformant = "Partial"
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notes = """
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Incorrectly accepts an instance-only attribute as satisfying a `ClassVar` protocol member.
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"""
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errors_diff = """
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Line 369: Expected 1 errors
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"""
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output = """
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./protocols_definition.py:30:10: Incompatible argument type for things: expected collections.abc.Iterable[./protocols_definition.py.SupportsClose] but got Literal[[1]] [incompatible_argument]
@@ -23,4 +28,5 @@ output = """
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./protocols_definition.py:339:0: Incompatible assignment: expected ./protocols_definition.py.Template6, got ./protocols_definition.py.Concrete6_Bad1 [incompatible_assignment]
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./protocols_definition.py:340:0: Incompatible assignment: expected ./protocols_definition.py.Template6, got ./protocols_definition.py.Concrete6_Bad2 [incompatible_assignment]
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./protocols_definition.py:341:0: Incompatible assignment: expected ./protocols_definition.py.Template6, got ./protocols_definition.py.Concrete6_Bad3 [incompatible_assignment]
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./protocols_definition.py:370:0: Incompatible assignment: expected ./protocols_definition.py.Template7, got ./protocols_definition.py.Concrete7_Bad2 [incompatible_assignment]
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"""

‎conformance/results/pyrefly/protocols_definition.toml‎

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Original file line numberDiff line numberDiff line change
@@ -24,4 +24,6 @@ ERROR protocols_definition.py:289:22-38: `Concrete5_Bad5` is not assignable to `
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ERROR protocols_definition.py:339:22-38: `Concrete6_Bad1` is not assignable to `Template6` [bad-assignment]
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ERROR protocols_definition.py:340:22-38: `Concrete6_Bad2` is not assignable to `Template6` [bad-assignment]
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ERROR protocols_definition.py:341:22-38: `Concrete6_Bad3` is not assignable to `Template6` [bad-assignment]
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ERROR protocols_definition.py:369:22-38: `Concrete7_Bad1` is not assignable to `Template7` [bad-assignment]
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ERROR protocols_definition.py:370:22-38: `Concrete7_Bad2` is not assignable to `Template7` [bad-assignment]
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"""

‎conformance/results/pyright/protocols_definition.toml‎

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Original file line numberDiff line numberDiff line change
@@ -97,6 +97,12 @@ protocols_definition.py:341:22 - error: Type "Concrete6_Bad3" is not assignable
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  "Concrete6_Bad3" is incompatible with protocol "Template6"
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    "val1" is writable in protocol
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    "val1" is not read-only in protocol (reportAssignmentType)
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protocols_definition.py:369:22 - error: Type "Concrete7_Bad1" is not assignable to declared type "Template7"
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  "Concrete7_Bad1" is incompatible with protocol "Template7"
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    "val1" is defined as a ClassVar in protocol (reportAssignmentType)
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protocols_definition.py:370:22 - error: Type "Concrete7_Bad2" is not assignable to declared type "Template7"
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  "Concrete7_Bad2" is incompatible with protocol "Template7"
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    "val1" is defined as a ClassVar in protocol (reportAssignmentType)
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"""
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conformance_automated = "Pass"
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errors_diff = """

‎conformance/results/results.html‎

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‎conformance/results/ty/protocols_definition.toml‎

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@@ -23,4 +23,6 @@ protocols_definition.py:289:22: error[invalid-assignment] Object of type `Concre
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protocols_definition.py:339:22: error[invalid-assignment] Object of type `Concrete6_Bad1` is not assignable to `Template6`
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protocols_definition.py:340:22: error[invalid-assignment] Object of type `Concrete6_Bad2` is not assignable to `Template6`
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protocols_definition.py:341:22: error[invalid-assignment] Object of type `Concrete6_Bad3` is not assignable to `Template6`
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protocols_definition.py:369:22: error[invalid-assignment] Object of type `Concrete7_Bad1` is not assignable to `Template7`
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protocols_definition.py:370:22: error[invalid-assignment] Object of type `Concrete7_Bad2` is not assignable to `Template7`
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"""

‎conformance/results/zuban/protocols_definition.toml‎

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@@ -67,4 +67,7 @@ protocols_definition.py:340: error: Incompatible types in assignment (expression
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protocols_definition.py:340: note: Protocol member Template6.val1 expected settable variable, got read-only attribute
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protocols_definition.py:341: error: Incompatible types in assignment (expression has type "Concrete6_Bad3", variable has type "Template6") [assignment]
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protocols_definition.py:341: note: Protocol member Template6.val1 expected settable variable, got read-only attribute
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protocols_definition.py:369: error: Incompatible types in assignment (expression has type "Concrete7_Bad1", variable has type "Template7") [assignment]
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protocols_definition.py:369: note: Protocol member Template7.val1 expected class variable, got instance variable
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protocols_definition.py:370: error: Incompatible types in assignment (expression has type "Concrete7_Bad2", variable has type "Template7") [assignment]
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"""

‎conformance/tests/protocols_class_objects.py‎

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@@ -105,5 +105,5 @@ class ConcreteC3(metaclass=CMeta):
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pc2: ProtoC2 = ConcreteC1 # OK
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pc3: ProtoC1 = ConcreteC2 # E
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pc4: ProtoC2 = ConcreteC2 # E
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pc5: ProtoC1 = ConcreteC3 # E
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pc5: ProtoC1 = ConcreteC3 # E?: Explicit ClassVar matching is unspecified
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pc6: ProtoC2 = ConcreteC3 # OK

‎conformance/tests/protocols_definition.py‎

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@@ -114,7 +114,7 @@ class Concrete2_Bad4:
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v2_bad1: Template2 = Concrete2_Bad1() # E
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v2_bad2: Template2 = Concrete2_Bad2() # E
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v2_bad3: Template2 = Concrete2_Bad3() # E
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v2_bad4: Template2 = Concrete2_Bad4() # E
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v2_bad4: Template2 = Concrete2_Bad4() # E?: Explicit ClassVar matching is unspecified
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class Template3(Protocol):
@@ -339,3 +339,32 @@ class Concrete6_Bad3:
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v6_bad1: Template6 = Concrete6_Bad1() # E
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v6_bad2: Template6 = Concrete6_Bad2() # E: named tuple is immutable
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v6_bad3: Template6 = Concrete6_Bad3() # E: dataclass is frozen
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# The specification leaves two possible interpretations of a ClassVar protocol
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# member. One interpretation requires the implementing attribute to be explicitly
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# declared with ClassVar. The other interpretation imposes only structural
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# requirements: the attribute must be readable and writable on the class object
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# and readable on instances of the class. Both interpretations therefore require
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# the following assignments to be rejected.
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class Template7(Protocol):
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val1: ClassVar[int]
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class Concrete7_Bad1:
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def __init__(self) -> None:
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self.val1: int = 42
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class Concrete7Meta(type):
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val1: int = 42
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class Concrete7_Bad2(metaclass=Concrete7Meta):
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pass
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v7_bad1: Template7 = Concrete7_Bad1() # E: val1 is not readable on the class object
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v7_bad2: Template7 = Concrete7_Bad2() # E: val1 is not readable on instances

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