diff options
| -rw-r--r-- | Lib/test/test_patma.py | 76 | ||||
| -rw-r--r-- | Misc/NEWS.d/next/Security/2021-07-25-20-04-54.bpo-44600.0WMldg.rst | 1 | ||||
| -rw-r--r-- | Python/compile.c | 16 |
3 files changed, 89 insertions, 4 deletions
diff --git a/Lib/test/test_patma.py b/Lib/test/test_patma.py index 69a648a..96c1726 100644 --- a/Lib/test/test_patma.py +++ b/Lib/test/test_patma.py @@ -3,6 +3,7 @@ import collections import dataclasses import enum import inspect +import sys import unittest @@ -3056,6 +3057,81 @@ class TestValueErrors(unittest.TestCase): self.assertIs(z, None) +class TestTracing(unittest.TestCase): + + def _test_trace(self, func, expected_linenos, *f_args): + actual_linenos = set() + def trace(frame, event, arg): + if frame.f_code.co_name == func.__name__: + relative_lineno = frame.f_lineno - func.__code__.co_firstlineno + actual_linenos.add(relative_lineno) + return trace + + sys.settrace(trace) + func(*f_args) + sys.settrace(None) + self.assertSetEqual(actual_linenos, expected_linenos) + + def test_default_case_traces_correctly_a(self): + def default_no_assign(command): # 0 + match command.split(): # 1 + case ["go", direction] if direction in "nesw": # 2 + return f"go {direction}" # 3 + case ["go", _]: # 4 + return "no go" # 5 + case _: # 6 + return "default" # 7 + + self._test_trace(default_no_assign, {0, 1, 2, 3}, "go n") + self._test_trace(default_no_assign, {0, 1, 2, 4, 5}, "go x") + self._test_trace(default_no_assign, {0, 1, 2, 4, 6, 7}, "spam") + + def test_default_case_traces_correctly_b(self): + def default_wildcard_assign(command): # 0 + match command.split(): # 1 + case ["go", direction] if direction in "nesw": # 2 + return f"go {direction}" # 3 + case ["go", _]: # 4 + return "no go" # 5 + case x: # 6 + return x # 7 + + self._test_trace(default_wildcard_assign, {0, 1, 2, 3}, "go n") + self._test_trace(default_wildcard_assign, {0, 1, 2, 4, 5}, "go x") + self._test_trace(default_wildcard_assign, {0, 1, 2, 4, 6, 7}, "spam") + + def test_default_case_traces_correctly_c(self): + def no_default(command): # 0 + match command.split(): # 1 + case ["go", direction] if direction in "nesw": # 2 + return f"go {direction}" # 3 + case ["go", _]: # 4 + return "no go" # 5 + + self._test_trace(no_default, {0, 1, 2, 3}, "go n") + self._test_trace(no_default, {0, 1, 2, 4, 5}, "go x") + self._test_trace(no_default, {0, 1, 2, 4}, "spam") + + def test_default_case_traces_correctly_d(self): + def only_default_no_assign(command): # 0 + match command.split(): # 1 + case _: # 2 + return "default" # 3 + + self._test_trace(only_default_no_assign, {0, 1, 2, 3}, "go n") + self._test_trace(only_default_no_assign, {0, 1, 2, 3} , "go x") + self._test_trace(only_default_no_assign, {0, 1, 2, 3}, "spam") + + def test_default_case_traces_correctly_e(self): + def only_default_wildcard_assign(command): # 0 + match command.split(): # 1 + case x: # 2 + return x # 3 + + self._test_trace(only_default_wildcard_assign, {0, 1, 2, 3}, "go n") + self._test_trace(only_default_wildcard_assign, {0, 1, 2, 3} , "go x") + self._test_trace(only_default_wildcard_assign, {0, 1, 2, 3}, "spam") + if __name__ == "__main__": """ # From inside environment using this Python, with pyperf installed: diff --git a/Misc/NEWS.d/next/Security/2021-07-25-20-04-54.bpo-44600.0WMldg.rst b/Misc/NEWS.d/next/Security/2021-07-25-20-04-54.bpo-44600.0WMldg.rst new file mode 100644 index 0000000..ea4e04f --- /dev/null +++ b/Misc/NEWS.d/next/Security/2021-07-25-20-04-54.bpo-44600.0WMldg.rst @@ -0,0 +1 @@ +Fix incorrect line numbers while tracing some failed patterns in :ref:`match <match>` statements. Patch by Charles Burkland.
\ No newline at end of file diff --git a/Python/compile.c b/Python/compile.c index 3a20f6b..7fb8abf 100644 --- a/Python/compile.c +++ b/Python/compile.c @@ -6576,17 +6576,25 @@ compiler_match_inner(struct compiler *c, stmt_ty s, pattern_context *pc) } VISIT_SEQ(c, stmt, m->body); ADDOP_JUMP(c, JUMP_FORWARD, end); + // If the pattern fails to match, we want the line number of the + // cleanup to be associated with the failed pattern, not the last line + // of the body + SET_LOC(c, m->pattern); RETURN_IF_FALSE(emit_and_reset_fail_pop(c, pc)); } if (has_default) { - if (cases == 1) { - // No matches. Done with the subject: - ADDOP(c, POP_TOP); - } // A trailing "case _" is common, and lets us save a bit of redundant // pushing and popping in the loop above: m = asdl_seq_GET(s->v.Match.cases, cases - 1); SET_LOC(c, m->pattern); + if (cases == 1) { + // No matches. Done with the subject: + ADDOP(c, POP_TOP); + } + else { + // Show line coverage for default case (it doesn't create bytecode) + ADDOP(c, NOP); + } if (m->guard) { RETURN_IF_FALSE(compiler_jump_if(c, m->guard, end, 0)); } |