fix: generator wrapping with Python 3.10 (#13835)

We fix an issue with generator wrapping with Python 3.10 that could have
caused an exception to be raised after the generator had been used and
exhausted.

The issue has been caught by the exploration tests.

- [x] PR author has checked that all the criteria below are met
- The PR description includes an overview of the change
- The PR description articulates the motivation for the change
- The change includes tests OR the PR description describes a testing
strategy
- The PR description notes risks associated with the change, if any
- Newly-added code is easy to change
- The change follows the [library release note
guidelines](https://ddtrace.readthedocs.io/en/stable/releasenotes.html)
- The change includes or references documentation updates if necessary
- Backport labels are set (if
[applicable](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting))

- [x] Reviewer has checked that all the criteria below are met
- Title is accurate
- All changes are related to the pull request's stated goal
- Avoids breaking
[API](https://ddtrace.readthedocs.io/en/stable/versioning.html#interfaces)
changes
- Testing strategy adequately addresses listed risks
- Newly-added code is easy to change
- Release note makes sense to a user of the library
- If necessary, author has acknowledged and discussed the performance
implications of this PR as reported in the benchmarks PR comment
- Backport labels are set in a manner that is consistent with the
[release branch maintenance
policy](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting)

(cherry picked from commit 5d10180)

Author: brettlangdon

ddtrace/_trace/tracer.py

@@ -775,8 +775,7 @@ def func_wrapper(*args, **kwargs):
                 )
 
             with self.trace(span_name, service=service, resource=resource, span_type=span_type):
-                return_value = yield from f(*args, **kwargs)
-                return return_value
+                yield from f(*args, **kwargs)
 
         return func_wrapper
 

ddtrace/contrib/internal/pytest/_plugin_v1.py

@@ -417,7 +417,7 @@ def _get_test_class_hierarchy(item):
 
 
 def pytest_load_initial_conftests(early_config, parser, args):
-    if _is_enabled_early(early_config, args):
+    if _is_enabled_early(early_config):
         # Enables experimental use of ModuleCodeCollector for coverage collection.
         from ddtrace.internal.ci_visibility.coverage import USE_DD_COVERAGE
         from ddtrace.internal.logger import get_logger

ddtrace/contrib/internal/pytest/_plugin_v2.py

@@ -209,7 +209,7 @@ def _pytest_load_initial_conftests_pre_yield(early_config, parser, args):
     ModuleCodeCollector has a tangible impact on the time it takes to load modules, so it should only be installed if
     coverage collection is requested by the backend.
     """
-    if not _is_enabled_early(early_config, args):
+    if not _is_enabled_early(early_config):
         return
 
     try:

ddtrace/contrib/internal/pytest/_utils.py

@@ -211,7 +211,7 @@ def _extract_span(item):
     return getattr(item, "_datadog_span", None)
 
 
-def _is_enabled_early(early_config, args):
+def _is_enabled_early(early_config):
     """Checks if the ddtrace plugin is enabled before the config is fully populated.
 
     This is necessary because the module watchdog for coverage collection needs to be enabled as early as possible.
@@ -222,14 +222,15 @@ def _is_enabled_early(early_config, args):
     if not _pytest_version_supports_itr():
         return False
 
-    if _is_option_true("no-ddtrace", early_config, args):
+    if (
+        "--no-ddtrace" in early_config.invocation_params.args
+        or early_config.getini("no-ddtrace")
+        or "ddtrace" in early_config.inicfg
+        and early_config.getini("ddtrace") is False
+    ):
         return False
 
-    return _is_option_true("ddtrace", early_config, args)
-
-
-def _is_option_true(option, early_config, args):
-    return early_config.getoption(option) or early_config.getini(option) or f"--{option}" in args
+    return "--ddtrace" in early_config.invocation_params.args or early_config.getini("ddtrace")
 
 
 class _TestOutcome(t.NamedTuple):

ddtrace/internal/wrapping/context.py

@@ -1,6 +1,7 @@
 from abc import ABC
 from contextvars import ContextVar
 from inspect import iscoroutinefunction
+from inspect import isgeneratorfunction
 import sys
 from types import FrameType
 from types import FunctionType
@@ -671,9 +672,9 @@ def wrap(self) -> None:
                     pass
                 i += 1
 
-            # Search for the GEN_START instruction
+            # Search for the GEN_START instruction, which needs to stay on top.
             i = 0
-            if sys.version_info >= (3, 10) and iscoroutinefunction(f):
+            if sys.version_info >= (3, 10) and (iscoroutinefunction(f) or isgeneratorfunction(f)):
                 for i, instr in enumerate(bc, 1):
                     try:
                         if instr.name == "GEN_START":

releasenotes/notes/ci_visibility-fix-pytest-addopts-early-init-74fb4e207dee18e4.yaml

@@ -0,0 +1,5 @@
+---
+fixes:
+  - |
+    dynamic instrumentation: fixed an issue with the instrumentation of
+    generators with Python 3.10.

releasenotes/notes/fix-generator-wrapping-86af0ae55ba2723a.yaml

@@ -218,41 +218,6 @@ def test_ini(ddspan):
 
         assert len(spans) == 4
 
-    def test_pytest_addopts_env_var(self):
-        """Test enabling ddtrace via the PYTEST_ADDOPTS environment variable."""
-        py_file = self.testdir.makepyfile(
-            """
-            import pytest
-
-            def test_trace(ddspan):
-                assert ddspan is not None
-        """
-        )
-        file_name = os.path.basename(py_file.strpath)
-        rec = self.inline_run(file_name, extra_env={"PYTEST_ADDOPTS": "--ddtrace"})
-        rec.assertoutcome(passed=1)
-        spans = self.pop_spans()
-
-        assert len(spans) == 4
-
-    def test_pytest_addopts_ini(self):
-        """Test enabling ddtrace via the `addopts` option in the ini file."""
-        self.testdir.makefile(".ini", pytest="[pytest]\naddopts = --ddtrace\n")
-        py_file = self.testdir.makepyfile(
-            """
-            import pytest
-
-            def test_ini(ddspan):
-                assert ddspan is not None
-        """
-        )
-        file_name = os.path.basename(py_file.strpath)
-        rec = self.inline_run(file_name)
-        rec.assertoutcome(passed=1)
-        spans = self.pop_spans()
-
-        assert len(spans) == 4
-
     def test_pytest_command(self):
         """Test that the pytest run command is stored on a test span."""
         py_file = self.testdir.makepyfile(