CI: Add keyword checks (#21451)

Author: dveeden

.github/workflows/keywords.yaml

@@ -0,0 +1,17 @@
+name: Keywords
+
+on:
+  pull_request:
+  push:
+    branches:
+      - 'master'
+
+jobs:
+  check-keywords:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v6
+      - run: |
+          ./scripts/check-keywords.py \
+          --download_from_url \
+          --parser_url https://github.com/pingcap/tidb/raw/refs/heads/${GITHUB_BASE_REF}/pkg/parser/parser.y

keywords.md

@@ -778,7 +778,7 @@ TiDB 从 v7.5.3 和 v7.6.0 开始提供 [`INFORMATION_SCHEMA.KEYWORDS`](/informa
 - VARCHARACTER (R)
 - VARIABLES
 - VARYING (R)
-- VECTOR 
+- VECTOR
 - VIEW
 - VIRTUAL (R)
 - VISIBLE

scripts/check-keywords.py

@@ -0,0 +1,84 @@
+#!/bin/python3
+import argparse
+import requests
+import re
+import sys
+from pathlib import Path
+
+aparser = argparse.ArgumentParser()
+aparser.add_argument(
+    "--parser_file", default="../tidb/pkg/parser/parser.y", help="Path to parser.y"
+)
+aparser.add_argument(
+    "--parser_url",
+    default="https://github.com/pingcap/tidb/raw/refs/heads/master/pkg/parser/parser.y",
+    help="URL to parser.y",
+)
+aparser.add_argument("--download_from_url", action="store_true")
+args = aparser.parse_args()
+
+if args.download_from_url:
+    try:
+        print(f"Fetching {args.parser_url}")
+        r = requests.get(args.parser_url, timeout=30)
+        r.raise_for_status()
+        lines = r.text.splitlines()
+    except requests.RequestException as e:
+        sys.exit(f"Failed to download parser file: {e}")
+else:
+    parser = Path(args.parser_file)
+    if not parser.exists():
+        sys.exit(f"{parser} doesn't exist")
+    lines = parser.read_text(encoding="utf-8").splitlines()
+
+kwdocs = Path("keywords.md")
+if not kwdocs.exists():
+    sys.exit(f"{kwdocs} doesn't exist")
+
+keywords = kwdocs.read_text()
+
+errors = 0
+section = "Unknown"
+for line in lines:
+    if line == "":
+        section = "NotKeywordToken"
+
+    elif line.find("The following tokens belong to ReservedKeyword") >= 0:
+        section = "ReservedKeyword"
+
+    elif line.find("The following tokens belong to UnReservedKeyword") >= 0:
+        section = "UnReservedKeyword"
+
+    elif line.find("The following tokens belong to TiDBKeyword") >= 0:
+        section = "TiDBKeyword"
+
+    elif line.find("The following tokens belong to NotKeywordToken") >= 0:
+        section = "NotKeywordToken"
+
+    if section == "ReservedKeyword":
+        if m := re.match(r'^\t\w+\s+"(\w+)"$', line):
+            kw = m.groups()[0]
+            if not (
+                kwm := re.search(f"^- {kw} \\((R|R-Window)\\)$", keywords, re.MULTILINE)
+            ):
+                if kwm := re.search(f"^- {kw}$", keywords, re.MULTILINE):
+                    print(f"Reserved keyword not labeled as reserved: {kw}")
+                else:
+                    print(f"Missing docs for reserved keyword: {kw}")
+                errors += 1
+
+    if section in ["UnReservedKeyword", "TiDBKeyword"]:
+        if m := re.match(r'^\t\w+\s+"(\w+)"$', line):
+            kw = m.groups()[0]
+            if not (kwm := re.search(f"^- {kw}$", keywords, re.MULTILINE)):
+                if kwm := re.search(
+                    f"^- {kw} \\((R|R-Window)\\)$", keywords, re.MULTILINE
+                ):
+                    print(
+                        f"Non-reserved keyword from {section} labeled as reserved: {kw}"
+                    )
+                else:
+                    print(f"Missing docs for non-reserved keyword from {section}: {kw}")
+                errors += 1
+
+sys.exit(errors)