build: collect per-test timing data.

Run pytest with extra reporting enabled to generate files with per-test
durations. The file is uploaded as a CI artifact so timing data can be
downloaded and used to drive optimal shard rebalancing.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: feanil

.github/workflows/unit-tests.yml

@@ -119,7 +119,16 @@ jobs:
       - name: run tests
         shell: bash
         run: |
-          python -Wd -m pytest -p no:randomly --ds=${{ env.settings_path }} ${{ env.unit_test_paths }} --cov=.
+          python -Wd -m pytest -p no:randomly --ds=${{ env.settings_path }} ${{ env.unit_test_paths }} --cov=. \
+            --report-log=reports/pytest-report-${{ matrix.shard_name }}.jsonl
+
+      - name: Upload pytest timing report
+        if: always()
+        uses: actions/upload-artifact@v7
+        with:
+          name: pytest-report-${{ matrix.shard_name }}-${{ matrix.python-version }}-${{ matrix.django-version }}-${{ matrix.mongo-version }}-${{ matrix.os-version }}
+          path: reports/pytest-report-${{ matrix.shard_name }}.jsonl
+          overwrite: true
 
       - name: rename warnings json file
         if: success()

requirements/edx/development.txt

@@ -1719,6 +1719,7 @@ pytest==8.2.0
     #   pytest-json-report
     #   pytest-metadata
     #   pytest-randomly
+    #   pytest-reportlog
     #   pytest-xdist
 pytest-attrib==0.1.3
     # via -r requirements/edx/testing.txt
@@ -1734,6 +1735,8 @@ pytest-metadata==3.1.1
     #   pytest-json-report
 pytest-randomly==4.0.1
     # via -r requirements/edx/testing.txt
+pytest-reportlog==1.0.0
+    # via -r requirements/edx/testing.txt
 pytest-xdist[psutil]==3.8.0
     # via -r requirements/edx/testing.txt
 python-dateutil==2.9.0.post0

requirements/edx/testing.in

@@ -38,6 +38,7 @@ pytest-django             # Django support for pytest
 pytest-json-report        # Output json formatted warnings after running pytest
 pytest-metadata           # To prevent 'make upgrade' failure, dependency of pytest-json-report
 pytest-randomly           # pytest plugin to randomly order tests
+pytest-reportlog          # Per-test timing data including setup/teardown (used for shard rebalancing)
 pytest-xdist[psutil]      # Parallel execution of tests on multiple CPU cores or hosts
 singledispatch            # Backport of functools.singledispatch from Python 3.4+, used in tests of XBlock rendering
 testfixtures              # Provides a LogCapture utility used by several tests

requirements/edx/testing.txt

@@ -1305,6 +1305,7 @@ pytest==8.2.0
     #   pytest-json-report
     #   pytest-metadata
     #   pytest-randomly
+    #   pytest-reportlog
     #   pytest-xdist
 pytest-attrib==0.1.3
     # via -r requirements/edx/testing.in
@@ -1320,6 +1321,8 @@ pytest-metadata==3.1.1
     #   pytest-json-report
 pytest-randomly==4.0.1
     # via -r requirements/edx/testing.in
+pytest-reportlog==1.0.0
+    # via -r requirements/edx/testing.in
 pytest-xdist[psutil]==3.8.0
     # via -r requirements/edx/testing.in
 python-dateutil==2.9.0.post0