From d6bd319db431e591627ca70c0ac62883c13e6aaa Mon Sep 17 00:00:00 2001
From: Stefan Hansson <newbyte@postmarketos.org>
Date: Fri, 11 Oct 2024 12:14:35 +0200
Subject: [PATCH 1/3] [mypyc] Support ellipsis (...) expressions in class
 bodies

This can be used to declare concise custom exceptions, e.g.

    class UnknownReleaseError(ValueError): ...

which otherwise probably would be written

    class UnknownReleaseError(ValueError):
        pass

and is supported by CPython.

Closes https://github.com/mypyc/mypyc/issues/1069
---
 mypyc/irbuild/classdef.py        |  7 ++++++-
 mypyc/test-data/run-classes.test | 20 ++++++++++++++++++++
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/mypyc/irbuild/classdef.py b/mypyc/irbuild/classdef.py
index 7e0a842b1b41..17ce7ea34776 100644
--- a/mypyc/irbuild/classdef.py
+++ b/mypyc/irbuild/classdef.py
@@ -12,6 +12,7 @@
     CallExpr,
     ClassDef,
     Decorator,
+    EllipsisExpr,
     ExpressionStmt,
     FuncDef,
     Lvalue,
@@ -145,7 +146,11 @@ def transform_class_def(builder: IRBuilder, cdef: ClassDef) -> None:
                 continue
             with builder.catch_errors(stmt.line):
                 cls_builder.add_method(get_func_def(stmt))
-        elif isinstance(stmt, PassStmt):
+        elif (
+            isinstance(stmt, PassStmt)
+            or (isinstance(stmt, ExpressionStmt)
+            and isinstance(stmt.expr, EllipsisExpr))
+        ):
             continue
         elif isinstance(stmt, AssignmentStmt):
             if len(stmt.lvalues) != 1:
diff --git a/mypyc/test-data/run-classes.test b/mypyc/test-data/run-classes.test
index 59617714f7e7..9b1a157439a3 100644
--- a/mypyc/test-data/run-classes.test
+++ b/mypyc/test-data/run-classes.test
@@ -18,6 +18,26 @@ True
 <native.Empty object
 True
 
+[case testEmptyClassEllipsis]
+class Empty: ...
+
+def f(e: Empty) -> Empty:
+    return e
+[file driver.py]
+from native import Empty, f
+
+print(isinstance(Empty, type))
+print(Empty)
+print(str(Empty())[:20])
+
+e = Empty()
+print(f(e) is e)
+[out]
+True
+<class 'native.Empty'>
+<native.Empty object
+True
+
 [case testClassWithFields]
 class C:
     x: int

From 86d1e39b8ef52156dc76a29a38c82b1d6337d594 Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Fri, 11 Oct 2024 19:25:44 +0000
Subject: [PATCH 2/3] [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci
---
 mypyc/irbuild/classdef.py | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/mypyc/irbuild/classdef.py b/mypyc/irbuild/classdef.py
index 17ce7ea34776..bcc9594adcb9 100644
--- a/mypyc/irbuild/classdef.py
+++ b/mypyc/irbuild/classdef.py
@@ -146,10 +146,8 @@ def transform_class_def(builder: IRBuilder, cdef: ClassDef) -> None:
                 continue
             with builder.catch_errors(stmt.line):
                 cls_builder.add_method(get_func_def(stmt))
-        elif (
-            isinstance(stmt, PassStmt)
-            or (isinstance(stmt, ExpressionStmt)
-            and isinstance(stmt.expr, EllipsisExpr))
+        elif isinstance(stmt, PassStmt) or (
+            isinstance(stmt, ExpressionStmt) and isinstance(stmt.expr, EllipsisExpr)
         ):
             continue
         elif isinstance(stmt, AssignmentStmt):

From ab32f6e5c07307d12a9de24c92e66e8e369c81b0 Mon Sep 17 00:00:00 2001
From: hauntsaninja <hauntsaninja@gmail.com>
Date: Sun, 13 Oct 2024 18:45:30 -0700
Subject: [PATCH 3/3] combine test cases

---
 mypyc/test-data/run-classes.test | 32 ++++++++++++++------------------
 1 file changed, 14 insertions(+), 18 deletions(-)

diff --git a/mypyc/test-data/run-classes.test b/mypyc/test-data/run-classes.test
index 9b1a157439a3..7c2998874f78 100644
--- a/mypyc/test-data/run-classes.test
+++ b/mypyc/test-data/run-classes.test
@@ -3,28 +3,13 @@ class Empty: pass
 
 def f(e: Empty) -> Empty:
     return e
-[file driver.py]
-from native import Empty, f
-
-print(isinstance(Empty, type))
-print(Empty)
-print(str(Empty())[:20])
-
-e = Empty()
-print(f(e) is e)
-[out]
-True
-<class 'native.Empty'>
-<native.Empty object
-True
 
-[case testEmptyClassEllipsis]
-class Empty: ...
+class EmptyEllipsis: ...
 
-def f(e: Empty) -> Empty:
+def g(e: EmptyEllipsis) -> EmptyEllipsis:
     return e
 [file driver.py]
-from native import Empty, f
+from native import Empty, EmptyEllipsis, f, g
 
 print(isinstance(Empty, type))
 print(Empty)
@@ -32,11 +17,22 @@ print(str(Empty())[:20])
 
 e = Empty()
 print(f(e) is e)
+
+print(isinstance(EmptyEllipsis, type))
+print(EmptyEllipsis)
+print(str(EmptyEllipsis())[:28])
+
+e2 = EmptyEllipsis()
+print(g(e2) is e2)
 [out]
 True
 <class 'native.Empty'>
 <native.Empty object
 True
+True
+<class 'native.EmptyEllipsis'>
+<native.EmptyEllipsis object
+True
 
 [case testClassWithFields]
 class C: