Include captured warnings in the log (#21)

Fixes #20

Author: keewis

src/pytest_reportlog/plugin.py

@@ -67,6 +67,23 @@ def pytest_runtest_logreport(self, report):
         )
         self._write_json_data(data)
 
+    def pytest_warning_recorded(self, warning_message, when, nodeid, location):
+        data = {
+            "category": (
+                warning_message.category.__name__ if warning_message.category else None
+            ),
+            "filename": warning_message.filename,
+            "lineno": warning_message.lineno,
+            "message": warning_message.message,
+        }
+        extra_data = {
+            "$report_type": "WarningMessage",
+            "when": when,
+            "location": location,
+        }
+        data.update(extra_data)
+        self._write_json_data(data)
+
     def pytest_collectreport(self, report):
         data = self._config.hook.pytest_report_to_serializable(
             config=self._config, report=report

tests/test_reportlog.py

@@ -1,4 +1,5 @@
 import json
+from collections import defaultdict
 
 import pytest
 from _pytest.reports import BaseReport
@@ -12,14 +13,19 @@ def test_basics(testdir, tmp_path, pytestconfig):
     We don't test the test reports extensively because they have been
     tested already in ``test_reports``.
     """
-    testdir.makepyfile(
+    p = testdir.makepyfile(
         """
+        import warnings
+
         def test_ok():
             pass
 
         def test_fail():
             assert 0
-    """
+
+        def test_warning():
+            warnings.warn("message", UserWarning)
+        """
     )
 
     log_file = tmp_path / "log.json"
@@ -29,7 +35,7 @@ def test_fail():
     result.stdout.fnmatch_lines([f"* generated report log file: {log_file}*"])
 
     json_objs = [json.loads(x) for x in log_file.read_text().splitlines()]
-    assert len(json_objs) == 10
+    assert len(json_objs) == 14
 
     # first line should be the session_start
     session_start = json_objs[0]
@@ -45,6 +51,22 @@ def test_fail():
         "$report_type": "SessionFinish",
     }
 
+    split = defaultdict(list)
+    for obj in json_objs:
+        split[obj["$report_type"] == "WarningMessage"].append(obj)
+    [warning] = split[True]
+    json_objs = split[False]
+
+    assert warning == {
+        "$report_type": "WarningMessage",
+        "category": "UserWarning",
+        "when": "runtest",
+        "message": "message",
+        "lineno": 10,
+        "location": None,  # seems to be hard-coded to None
+        "filename": str(p),
+    }
+
     # rest of the json objects should be unserialized into report objects; we don't test
     # the actual report object extensively because it has been tested in ``test_reports``
     # already.
@@ -60,16 +82,21 @@ def test_xdist_integration(testdir, tmp_path):
     pytest.importorskip("xdist")
     testdir.makepyfile(
         """
+        import warnings
+
         def test_ok():
             pass
 
         def test_fail():
             assert 0
-    """
+
+        def test_warning():
+            warnings.warn("message", UserWarning)
+        """
     )
     fn = tmp_path / "result.log"
     result = testdir.runpytest("-n2", f"--report-log={fn}")
-    result.stdout.fnmatch_lines("*1 failed, 1 passed*")
+    result.stdout.fnmatch_lines("*1 failed, 2 passed, 1 warning*")
 
     lines = fn.read_text("UTF-8").splitlines()
     data = json.loads(lines[0])