From 7f435c12084c847bea3fe7f186c1385eca3ac0c2 Mon Sep 17 00:00:00 2001
From: Juan Altmayer Pizzorno <juan@altmayer.com>
Date: Tue, 18 Jun 2024 10:46:07 -0400
Subject: [PATCH] - fixed bugs in 'match' wildcard detection, for when a
 wildcard is   included OR'ed with other cases (absurd) or with a guard.  
 Thanks to Ned Batchelder;

---
 src/slipcover/branch.py  |  6 +++--
 src/slipcover/version.py |  2 +-
 tests/test_branch.py     | 50 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 55 insertions(+), 3 deletions(-)

diff --git a/src/slipcover/branch.py b/src/slipcover/branch.py
index 111ee86..6fea877 100644
--- a/src/slipcover/branch.py
+++ b/src/slipcover/branch.py
@@ -87,9 +87,11 @@ def visit_Match(self, node: ast.Match) -> ast.Match:
                 for case in node.cases:
                     case.body = self._mark_branch(node.lineno, case.body[0].lineno) + case.body
 
-                has_wildcard = isinstance(node.cases[-1].pattern, ast.MatchAs) and \
-                               node.cases[-1].pattern.pattern is None
+                last_pattern = case.pattern  # case is node.cases[-1]
+                while isinstance(last_pattern, ast.MatchOr):
+                    last_pattern = last_pattern.patterns[-1]
 
+                has_wildcard = case.guard is None and isinstance(last_pattern, ast.MatchAs) and last_pattern.pattern is None
                 if not has_wildcard:
                     to_line = node.next_node.lineno if node.next_node else 0 # exit
                     node.cases.append(ast.match_case(ast.MatchAs(),
diff --git a/src/slipcover/version.py b/src/slipcover/version.py
index b19b12e..f871089 100644
--- a/src/slipcover/version.py
+++ b/src/slipcover/version.py
@@ -1 +1 @@
-__version__ = "1.0.14"
+__version__ = "1.0.15"
diff --git a/tests/test_branch.py b/tests/test_branch.py
index 87952aa..51fd969 100644
--- a/tests/test_branch.py
+++ b/tests/test_branch.py
@@ -547,6 +547,22 @@ def test_match_case_with_false_guard():
         assert [(3,7)] == g[br.BRANCH_NAME]
 
 
+@pytest.mark.skipif(PYTHON_VERSION < (3,10), reason="New in 3.10")
+def test_match_case_with_guard_isnt_wildcard():
+    t = ast_parse("""
+        def fun(v):
+            match v:
+                case _ if v > 0:
+                    print("not default")
+    """)
+
+
+    t = br.preinstrument(t)
+    check_locations(t)
+    code = compile(t, "foo", "exec")
+    assert [(2,0), (2,4)] == get_branches(code)
+
+
 @pytest.mark.skipif(PYTHON_VERSION < (3,10), reason="New in 3.10")
 def test_match_branch_to_exit():
     t = ast_parse("""
@@ -693,6 +709,39 @@ def test_branch_after_case_with_next():
         assert [(2,4), (4,9)] == g[br.BRANCH_NAME]
 
 
+@pytest.mark.skipif(PYTHON_VERSION < (3,10), reason="New in 3.10")
+def test_match_wildcard_in_match_or():
+    # Thanks to Ned Batchelder for this test case
+    t = ast_parse(f"""
+            def absurd(x):
+                match x:
+                    case (3 | 99 | (999 | _)):
+                        print("default")
+            absurd(5)
+            """)
+
+    t = br.preinstrument(t)
+    check_locations(t)
+    code = compile(t, "foo", "exec")
+    assert [(2,4)] == get_branches(code)
+
+
+@pytest.mark.skipif(PYTHON_VERSION < (3,10), reason="New in 3.10")
+def test_match_capture():
+    t = ast_parse(f"""
+            def capture(x):
+                match x:
+                    case y:
+                        print("default")
+            capture(5)
+            """)
+
+    t = br.preinstrument(t)
+    check_locations(t)
+    code = compile(t, "foo", "exec")
+    assert [(2,4)] == get_branches(code)
+
+
 @pytest.mark.parametrize("star", ['', '*'] if PYTHON_VERSION >= (3,11) else [''])
 def test_try_except(star):
     t = ast_parse(f"""
@@ -781,3 +830,4 @@ def foo(x):
     check_locations(t)
     code = compile(t, "foo", "exec")
     assert [(4,5), (4,10), (7,8), (7,13), (10,11), (10,13)] == get_branches(code)
+