fix(ci): honor splits for --fork= release features

The `parse_until_fork` gate in `generate_build_matrix.build_matrix`
silently disabled `splits: 4` for the `benchmark` feature because it
uses `--fork=Osaka` rather than `--until=`. That check only belongs in
`pre_alloc_matrix` (phase 1 fork-range splitting); pytest-split (phase
2) should apply whenever `splits > 1`.

Dropping the gate requires two follow-on fixes for the new
`--fork=`-with-splits path:

- Gate `--use-pre-alloc-groups` on `pre_alloc_labels` rather than on
  `matrix.label`. `--fork=` features skip phase 1, so no groups folder
  exists and `fill` would raise `FileNotFoundError`.
- Move `benchmark_genesis` generation to the `combine` job. Split
  builds no longer produce an unsplit `fixtures_benchmark.tar.gz` in
  `build-fixtures`; the merged tarball is only available after combine.
  The unsplit path in `build-fixtures` still covers `benchmark_fast`.

Author: danceratopz

.github/scripts/generate_build_matrix.py

@@ -102,7 +102,7 @@ def build_matrix(feature: dict, name: str) -> tuple[list[dict], str]:
     """
     splits = feature.get("splits", 0)
 
-    if splits > 1 and parse_until_fork(feature["fill-params"]):
+    if splits > 1:
         build = [
             {
                 "feature": name,

.github/scripts/tests/test_release_scripts.py

@@ -51,9 +51,7 @@ def test_split_feature_produces_entries_per_group(self):
         assert out["feature_name"] == "mainnet"
         assert out["combine_labels"] != ""
         splits = matrix[0]["splits"]
-        assert [e["group"] for e in matrix] == list(
-            range(1, splits + 1)
-        )
+        assert [e["group"] for e in matrix] == list(range(1, splits + 1))
         assert all(e["splits"] == splits for e in matrix)
         assert all(e["label"] == str(e["group"]) for e in matrix)
 
@@ -69,18 +67,36 @@ def test_split_feature_produces_pre_alloc_matrix(self):
         assert out["pre_alloc_labels"] != ""
 
     def test_unsplit_feature_produces_single_entry(self):
-        """Verify a single-fork feature produces one unsplit entry."""
-        result = run_script(BUILD_MATRIX_SCRIPT, "benchmark")
+        """Verify a feature without splits configured produces one entry."""
+        result = run_script(BUILD_MATRIX_SCRIPT, "benchmark_fast")
         assert result.returncode == 0
         out = parse_matrix_output(result.stdout)
         matrix = json.loads(out["build_matrix"])
         assert len(matrix) == 1
-        assert out["feature_name"] == "benchmark"
+        assert out["feature_name"] == "benchmark_fast"
         assert out["combine_labels"] == ""
         assert matrix[0]["label"] == ""
         assert matrix[0]["splits"] == 0
         assert matrix[0]["group"] == 0
 
+    def test_split_feature_with_fork_param(self):
+        """Verify splits apply to --fork features, not just --until."""
+        result = run_script(BUILD_MATRIX_SCRIPT, "benchmark")
+        assert result.returncode == 0
+        out = parse_matrix_output(result.stdout)
+        matrix = json.loads(out["build_matrix"])
+        assert len(matrix) > 1
+        assert out["feature_name"] == "benchmark"
+        splits = matrix[0]["splits"]
+        assert [e["group"] for e in matrix] == list(range(1, splits + 1))
+        assert all(e["splits"] == splits for e in matrix)
+        assert all(e["label"] == str(e["group"]) for e in matrix)
+        assert out["combine_labels"] == " ".join(
+            str(i) for i in range(1, splits + 1)
+        )
+        # --fork features should not generate a pre-alloc matrix.
+        assert json.loads(out["pre_alloc_matrix"]) == []
+
     def test_feature_only_can_be_requested_explicitly(self):
         """Verify feature_only entries work when named directly."""
         result = run_script(BUILD_MATRIX_SCRIPT, "bal")

.github/workflows/release_fixture_feature.yaml

@@ -210,7 +210,7 @@ jobs:
           splits: ${{ matrix.splits }}
           group: ${{ matrix.group }}
           store_durations: "true"
-          use_pre_alloc_groups: ${{ matrix.label != '' && 'true' || 'false' }}
+          use_pre_alloc_groups: ${{ needs.setup.outputs.pre_alloc_labels != '' && 'true' || 'false' }}
 
   combine:
     name: combine (${{ needs.setup.outputs.feature_name }})
@@ -287,6 +287,17 @@ jobs:
         with:
           name: fixtures_${{ needs.setup.outputs.feature_name }}
           path: fixtures_${{ needs.setup.outputs.feature_name }}.tar.gz
+      - name: Generate Benchmark Genesis Files
+        if: contains(needs.setup.outputs.feature_name, 'benchmark')
+        uses: ./.github/actions/build-benchmark-genesis
+        with:
+          fixtures_path: fixtures_${{ needs.setup.outputs.feature_name }}.tar.gz
+      - name: Upload Benchmark Genesis Artifact
+        if: contains(needs.setup.outputs.feature_name, 'benchmark')
+        uses: actions/upload-artifact@bbbca2ddaa5d8feaa63e36b76fdaad77386f024f # v7.0.0
+        with:
+          name: benchmark_genesis_${{ needs.setup.outputs.feature_name }}
+          path: benchmark_genesis.tar.gz
 
   release:
     runs-on: ubuntu-latest