Community Markdown validation works without PR-template files

.github/dependabot.yml

@@ -0,0 +1,12 @@
+---
+version: 2
+updates:
+  - package-ecosystem: github-actions
+    directory: /
+    schedule:
+      interval: weekly
+
+  - package-ecosystem: npm
+    directory: /
+    schedule:
+      interval: weekly

.github/linters/.markdown-lint.yml

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+###########################
+## Markdown Linter rules ##
+###########################
+
+# Linter rules doc:
+# - https://github.com/DavidAnson/markdownlint
+
+###############
+# Rules by id #
+###############
+MD004: false                  # Unordered list style
+MD007:
+  indent: 2                   # Unordered list indentation
+MD013:
+  line_length: 3000           # Line length
+MD025:
+  front_matter_title: ""      # Allow a body H1 alongside the front matter title
+MD026:
+  punctuation: ".,;:!。，；:"    # List of not allowed
+MD029: false                  # Ordered list item prefix
+MD033: false                  # Allow inline HTML
+MD036: false                  # Emphasis used instead of a heading
+MD041: false                  # First line in file should be a top level heading, PULL_REQUEST_TEMPLATE.md is an exception
+MD060: false                  # Table column style — content mixes compact and aligned tables
+
+#################
+# Rules by tags #
+#################
+blank_lines: false  # Error on blank lines

.github/scripts/validate-markdown.mjs

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+import { spawnSync } from 'node:child_process';
+import { lstatSync, readFileSync, realpathSync } from 'node:fs';
+import { isAbsolute, join, relative, resolve, sep } from 'node:path';
+import { fileURLToPath } from 'node:url';
+import { lint, readConfig } from 'markdownlint-cli2/markdownlint/promise';
+import yamlParse from 'markdownlint-cli2/parsers/yaml';
+
+/** Read repository file metadata without invoking a shell. */
+function readGitOutput(directory, args) {
+  const result = spawnSync('git', ['-C', directory, ...args], { encoding: 'utf8' });
+  if (result.error) {
+    throw result.error;
+  }
+  if (result.status !== 0) {
+    throw new Error(`Git file discovery failed in ${JSON.stringify(directory)}: ${JSON.stringify(result.stderr.trim())}`);
+  }
+  return result.stdout;
+}
+
+/** Select existing tracked and nonignored Markdown, retaining Git symlink metadata. */
+function findMarkdownFiles(directory) {
+  const deleted = new Set(readGitOutput(directory, ['ls-files', '--deleted', '-z']).split('\0'));
+  const files = readGitOutput(directory, [
+    'ls-files', '--cached', '--others', '--exclude-standard', '--deduplicate', '-z',
+  ]).split('\0')
+    .filter((name) => !deleted.has(name))
+    .filter((name) => /\.(?:md|markdown)$/i.test(name) && !name.split('/').includes('node_modules'))
+    .map((name) => join(directory, ...name.split('/')))
+    .sort();
+  // Git symlinks can be ordinary path-text files in Windows checkouts.
+  const symlinks = new Set(readGitOutput(directory, ['ls-files', '--stage', '-z'])
+    .split('\0')
+    .filter((record) => record.startsWith('120000 '))
+    .map((record) => join(directory, ...record.slice(record.indexOf('\t') + 1).split('/'))));
+  return { files, symlinks };
+}
+
+// Optional first argument selects an isolated root; the shared rules stay fixed.
+const directory = resolve(process.argv[2] ?? process.cwd());
+if (!lstatSync(directory).isDirectory()) {
+  throw new Error(`Validation root is not a directory: ${JSON.stringify(directory)}`);
+}
+const repositoryRoot = readGitOutput(directory, ['rev-parse', '--show-toplevel']).replace(/\r?\n$/, '');
+const resolvedRepositoryRoot = realpathSync(directory);
+if (resolvedRepositoryRoot !== realpathSync(repositoryRoot)) {
+  throw new Error(`Validation must run from the repository root: ${JSON.stringify(repositoryRoot)}`);
+}
+const configurationPath = fileURLToPath(new URL('../linters/.markdown-lint.yml', import.meta.url));
+const configuration = await readConfig(configurationPath, [yamlParse]);
+const { files, symlinks } = findMarkdownFiles(directory);
+if (files.length === 0) {
+  throw new Error(`No Markdown files were checked in ${JSON.stringify(directory)}. Check the validation root.`);
+}
+const contributionSource = join(directory, '.github', 'CONTRIBUTING.md');
+if (!files.includes(contributionSource)) {
+  throw new Error(`Required community file is missing from the validation input: ${JSON.stringify(contributionSource)}. Restore the file or explicitly change the contract.`);
+}
+for (const file of files) {
+  const metadata = lstatSync(file);
+  if (metadata.isSymbolicLink() || symlinks.has(file)) {
+    throw new Error(`Markdown symlinks are not allowed: ${JSON.stringify(file)}. Use a regular file instead.`);
+  }
+  if (!metadata.isFile()) {
+    throw new Error(`Markdown input must be a regular file: ${JSON.stringify(file)}`);
+  }
+  const resolvedLocation = relative(resolvedRepositoryRoot, realpathSync(file));
+  if (resolvedLocation === '..' || resolvedLocation.startsWith(`..${sep}`) || isAbsolute(resolvedLocation)) {
+    throw new Error(`Markdown input resolves outside the repository root: ${JSON.stringify(file)}. Use a repository-local source.`);
+  }
+  if (readFileSync(file, 'utf8').trim().length === 0) {
+    throw new Error(`Empty Markdown file: ${JSON.stringify(file)}. Restore its content before validation.`);
+  }
+}
+
+const results = await lint({ files, config: configuration });
+const checkedFiles = Object.keys(results);
+if (checkedFiles.length !== files.length) {
+  throw new Error(`Markdown lint checked ${checkedFiles.length} of ${files.length} selected files.`);
+}
+for (const file of checkedFiles) {
+  console.log(JSON.stringify(relative(directory, file)));
+}
+const hasErrors = Object.values(results).some((errors) => errors.length > 0);
+if (hasErrors) {
+  console.error(JSON.stringify(results, null, 2));
+}
+console.log(`Checked ${checkedFiles.length} Markdown files; result: ${hasErrors ? 'failed' : 'passed'}.`);
+process.exitCode = hasErrors ? 1 : 0;