From aff04ac8648b6109a27f9ccda34c0d9ab1026eff Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?St=C3=A9phane=20Lozier?= <slozier@users.noreply.github.com>
Date: Sat, 20 Mar 2021 11:42:48 -0400
Subject: [PATCH] Enable test_contextlib

---
 .../PythonExceptions.BaseException.cs         |  5 +---
 .../Cases/CPythonCasesManifest.ini            |  4 ---
 tests/suite/test_exceptions.py                | 29 ++++++++++++++++---
 3 files changed, 26 insertions(+), 12 deletions(-)

diff --git a/src/core/IronPython/Runtime/Exceptions/PythonExceptions.BaseException.cs b/src/core/IronPython/Runtime/Exceptions/PythonExceptions.BaseException.cs
index 6a7bc59e5..cedf7eb7f 100644
--- a/src/core/IronPython/Runtime/Exceptions/PythonExceptions.BaseException.cs
+++ b/src/core/IronPython/Runtime/Exceptions/PythonExceptions.BaseException.cs
@@ -278,9 +278,6 @@ public BaseException? __context__ {
                 get {
                     return _context ?? __cause__;
                 }
-                internal set {
-                    _context = value;
-                }
             }
 
             public bool __suppress_context__ { get; set; }
@@ -363,7 +360,7 @@ protected internal virtual void InitializeFromClr(System.Exception/*!*/ exceptio
 
             internal Exception CreateClrExceptionWithCause(BaseException? cause, BaseException? context, bool suppressContext) {
                 _cause = cause;
-                _context = context;
+                if (context != this) _context = context;
                 __suppress_context__ = suppressContext;
                 _traceback = null;
 
diff --git a/tests/IronPython.Tests/Cases/CPythonCasesManifest.ini b/tests/IronPython.Tests/Cases/CPythonCasesManifest.ini
index b3f7c5f00..5e83abc85 100644
--- a/tests/IronPython.Tests/Cases/CPythonCasesManifest.ini
+++ b/tests/IronPython.Tests/Cases/CPythonCasesManifest.ini
@@ -275,10 +275,6 @@ Ignore=true
 Ignore=true
 Reason=ImportError: Cannot import name SemLock
 
-[CPython.test_contextlib]
-Ignore=true
-Reason=Hangs
-
 [CPython.test_copy]
 IsolationLevel=ENGINE
 MaxRecursion=100
diff --git a/tests/suite/test_exceptions.py b/tests/suite/test_exceptions.py
index a2688c595..5e0996a07 100644
--- a/tests/suite/test_exceptions.py
+++ b/tests/suite/test_exceptions.py
@@ -87,11 +87,8 @@ def test_finally_continue_nested_finally_fails(self):
         finally:
             continue
 '''
-        try:
+        with self.assertRaises(SyntaxError):
             compile(t, '<test>', 'exec')
-            self.fail("Should raise SyntaxError")
-        except SyntaxError:
-            pass
 
     def test_bigint_division(self):
         def divide(a, b):
@@ -1079,4 +1076,28 @@ def f():
 
         self.assertRaises(error, f)
 
+    def test_reraise_context(self):
+        # reraising an exception should preserve the context
+        ex1 = Exception(1)
+        try:
+            try:
+                raise ex1
+            except:
+                raise ex1
+        except Exception as e:
+            self.assertIsNone(e.__context__)
+
+        ex1 = Exception(1)
+        ex2 = Exception(2)
+        try:
+            try:
+                try:
+                    raise ex2
+                except:
+                    raise ex1
+            except:
+                raise ex1
+        except Exception as e:
+            self.assertIs(e.__context__, ex2)
+
 run_test(__name__)