Revert change to traceback repr (#7535)

* Revert change to traceback repr

* Add test and changelog entry

* Restore *exact* prev output

Co-authored-by: Bruno Oliveira <nicoddemus@gmail.com>

changelog/7534.bugfix.rst

@@ -0,0 +1 @@
+Restored the previous formatting of ``TracebackEntry.__str__`` which was changed by accident.

src/_pytest/_code/code.py

@@ -262,7 +262,15 @@ class TracebackEntry:
             raise
         except BaseException:
             line = "???"
-        return "  File %r:%d in %s\n  %s\n" % (self.path, self.lineno + 1, name, line)
+        # This output does not quite match Python's repr for traceback entries,
+        # but changing it to do so would break certain plugins.  See
+        # https://github.com/pytest-dev/pytest/pull/7535/ for details.
+        return "  File %r:%d in %s\n  %s\n" % (
+            str(self.path),
+            self.lineno + 1,
+            name,
+            line,
+        )
 
     @property
     def name(self) -> str:

testing/code/test_code.py

@@ -1,3 +1,4 @@
+import re
 import sys
 from types import FrameType
 from unittest import mock
@@ -170,6 +171,15 @@ class TestTracebackEntry:
         assert len(source) == 6
         assert "assert False" in source[5]
 
+    def test_tb_entry_str(self):
+        try:
+            assert False
+        except AssertionError:
+            exci = ExceptionInfo.from_current()
+        pattern = r"  File '.*test_code.py':\d+ in test_tb_entry_str\n  assert False"
+        entry = str(exci.traceback[0])
+        assert re.match(pattern, entry)
+
 
 class TestReprFuncArgs:
     def test_not_raise_exception_with_mixed_encoding(self, tw_mock) -> None: