chore(di): fix top of stack in function snapshots [backport 2.16] (#11417)

Backport 9f6776d from #11239 to 2.16.

We fix a regression introduced with #11153 whereby the top of the stack
might have incorrect line number information

## Checklist
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- The change includes or references documentation updates if necessary
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[applicable](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting))

## Reviewer Checklist
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- Title is accurate
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Co-authored-by: Gabriele N. Tornetta <[email protected]>

Author: github-actions[bot]

ddtrace/debugging/_signal/snapshot.py

@@ -137,6 +137,17 @@ def exit(self, retval, exc_info, duration, scope) -> None:
         self.duration = duration
         self.return_capture = self._do(retval, exc_info, scope)
 
+        # Fix the line number of the top frame. This might have been mangled by
+        # the instrumented exception handling of function probes.
+        assert self._stack is not None  # nosec B101
+        tb = exc_info[2]
+        while tb is not None:
+            frame = tb.tb_frame
+            if frame == self.frame:
+                self._stack[0]["lineNumber"] = tb.tb_lineno
+                break
+            tb = tb.tb_next
+
     def line(self, scope) -> None:
         self.line_capture = self._do(_NOTSET, sys.exc_info(), scope)
 

tests/debugging/test_debugger.py

@@ -207,6 +207,7 @@ def test_debugger_function_probe_on_function_with_exception():
     snapshot_data = snapshot["debugger"]["snapshot"]
     assert snapshot_data["stack"][0]["fileName"].endswith("stuff.py")
     assert snapshot_data["stack"][0]["function"] == "throwexcstuff"
+    assert snapshot_data["stack"][0]["lineNumber"] == 110
 
     entry_capture = snapshot_data["captures"]["entry"]
     assert entry_capture["arguments"] == {}