ci: Add slang linting

Author: niwis

.github/workflows/run_slang.py

@@ -0,0 +1,28 @@
+#!/usr/bin/env python3
+"""Run slang on a file list via pyslang's Driver API and emit a JSON diagnostic file."""
+
+import sys
+import pyslang.driver as slang_driver
+
+
+def main():
+    if len(sys.argv) != 3:
+        print(f"Usage: {sys.argv[0]} <flist> <output.json>", file=sys.stderr)
+        sys.exit(1)
+
+    flist, output_json = sys.argv[1], sys.argv[2]
+
+    driver = slang_driver.Driver()
+    driver.parseCommandLine(
+        f"-f {flist}"
+        f" --top axi_lint_top"
+        f" --error-limit 0"
+        f" --diag-json {output_json}"
+    )
+    driver.runFullCompilation()
+    # Exit 0 regardless of compile errors so the CI step continues
+    # and reviewdog can annotate the diagnostics.
+
+
+if __name__ == "__main__":
+    main()

.github/workflows/slang.yml

@@ -0,0 +1,45 @@
+name: Slang lint
+
+on:
+  push:
+  pull_request:
+  workflow_dispatch:
+
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      checks: write
+      pull-requests: write
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install Bender
+        uses: pulp-platform/pulp-actions/bender-install@v2.4.5
+
+      - name: Install pyslang
+        run: pip install pyslang
+
+      - name: Generate file list
+        run: bender script flist-plus -t lint > sources.flist
+
+      - name: Run slang
+        run: python3 .github/workflows/run_slang.py sources.flist slang_diags.json
+
+      - name: Setup reviewdog
+        uses: reviewdog/action-setup@v1
+        with:
+          reviewdog_version: latest
+
+      - name: Run reviewdog
+        env:
+          REVIEWDOG_GITHUB_API_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          python3 .github/workflows/slang_to_rdjson.py slang_diags.json \
+            | reviewdog -f=rdjson \
+                -name=slang \
+                -reporter=${{ github.event_name == 'pull_request' && 'github-pr-review' || 'github-check' }} \
+                -filter-mode=nofilter \
+                -fail-level=error

.github/workflows/slang_to_rdjson.py

@@ -0,0 +1,71 @@
+#!/usr/bin/env python3
+"""Convert slang JSON diagnostic output to reviewdog rdjson format."""
+
+import json
+import re
+import sys
+
+SEVERITY_MAP = {
+    "error":   "ERROR",
+    "fatal":   "ERROR",
+    "warning": "WARNING",
+    "note":    "INFO",
+    "info":    "INFO",
+}
+
+LOCATION_RE = re.compile(r'^(.+):(\d+):(\d+)$')
+
+
+def parse_location(location_str):
+    """Parse 'path:line:col' into a rdjson location object."""
+    m = LOCATION_RE.match(location_str)
+    if not m:
+        return {"path": location_str}
+    return {
+        "path": m.group(1),
+        "range": {
+            "start": {
+                "line":   int(m.group(2)),
+                "column": int(m.group(3)),
+            }
+        },
+    }
+
+
+def convert(slang_diagnostics):
+    diagnostics = []
+    for d in slang_diagnostics:
+        entry = {
+            "message":  d.get("message", ""),
+            "location": parse_location(d.get("location", "")),
+            "severity": SEVERITY_MAP.get(d.get("severity", "").lower(), "WARNING"),
+        }
+        option_name = d.get("optionName")
+        if option_name:
+            entry["code"] = {"value": option_name}
+            if entry["severity"] == "WARNING":
+                entry["code"]["url"] = "https://sv-lang.com/warning-ref.html#" + option_name
+        diagnostics.append(entry)
+
+    return {
+        "source": {
+            "name": "slang",
+            "url":  "https://sv-lang.com",
+        },
+        "diagnostics": diagnostics,
+    }
+
+
+def main():
+    if len(sys.argv) != 2:
+        print(f"Usage: {sys.argv[0]} <slang-output.json>", file=sys.stderr)
+        sys.exit(1)
+    with open(sys.argv[1]) as f:
+        slang_diagnostics = json.load(f)
+    result = convert(slang_diagnostics)
+    json.dump(result, sys.stdout, indent=2)
+    sys.stdout.write("\n")
+
+
+if __name__ == "__main__":
+    main()