Refactoring: Split up script

pr-checks/update-builtin-languages.ts

@@ -1,6 +1,6 @@
 #!/usr/bin/env npx tsx
 
-/**
+/*
  * Updates src/languages/builtin.json by querying the CodeQL CLI for:
  * - Languages that have default queries (via codeql-extractor.yml)
  * - Language aliases (via `codeql resolve languages --format=betterjson --extractor-include-aliases`)
@@ -19,69 +19,107 @@ import * as yaml from "yaml";
 
 import { BUILTIN_LANGUAGES_FILE } from "./config";
 
-const codeqlPath = process.argv[2] || "codeql";
-
-// Step 1: Resolve all language extractor directories.
-const resolveJson: Record<string, string[]> = JSON.parse(
-  execFileSync(codeqlPath, ["resolve", "languages", "--format=json"], {
-    encoding: "utf8",
-  }),
-);
-
-// Step 2: For each language, read codeql-extractor.yml and check default_queries.
-const languages: string[] = [];
-
-for (const [language, dirs] of Object.entries(resolveJson)) {
-  const extractorDir = dirs[0];
-  const extractorYmlPath = path.join(extractorDir, "codeql-extractor.yml");
-
-  if (!fs.existsSync(extractorYmlPath)) {
-    throw new Error(
-      `Extractor YAML not found for language '${language}' at expected path: ${extractorYmlPath}`,
-    );
-  }
-
-  const extractorYml = yaml.parse(fs.readFileSync(extractorYmlPath, "utf8"));
-  const defaultQueries: unknown[] | undefined = extractorYml.default_queries;
-
-  if (Array.isArray(defaultQueries) && defaultQueries.length > 0) {
-    console.log(
-      `  ✅ ${language}: included (default queries: ${JSON.stringify(defaultQueries)})`,
-    );
-    languages.push(language);
-  } else {
-    console.log(`  ❌ ${language}: excluded (no default queries)`);
-  }
+/** Resolve all known language extractor directories. */
+function resolveLanguages(codeqlPath: string): Record<string, string[]> {
+  return JSON.parse(
+    execFileSync(codeqlPath, ["resolve", "languages", "--format=json"], {
+      encoding: "utf8",
+    }),
+  ) as Record<string, string[]>;
 }
 
-languages.sort();
+/**
+ * Return the sorted list of languages whose extractors ship default queries.
+ *
+ * @param extractorDirs - Map from language to list of extractor directories
+ */
+function findLanguagesWithDefaultQueries(
+  extractorDirs: Record<string, string[]>,
+): string[] {
+  const languages: string[] = [];
 
-// Step 3: Resolve aliases, filtered to only those targeting included languages.
-const betterjsonOutput = JSON.parse(
-  execFileSync(
-    codeqlPath,
-    [
-      "resolve",
-      "languages",
-      "--format=betterjson",
-      "--extractor-include-aliases",
-    ],
-    { encoding: "utf8" },
-  ),
-);
+  for (const [language, dirs] of Object.entries(extractorDirs)) {
+    if (dirs.length !== 1) {
+      throw new Error(
+        `Expected exactly one extractor directory for language '${language}', but found ${dirs.length}: ${dirs.join(
+          ", ",
+        )}`,
+      );
+    }
 
-const languageSet = new Set(languages);
-const aliases: Record<string, string> = Object.fromEntries(
-  Object.entries((betterjsonOutput.aliases ?? {}) as Record<string, string>)
-    .filter(([, target]) => languageSet.has(target))
-    .sort(([a], [b]) => a.localeCompare(b)),
-);
+    const extractorYmlPath = path.join(dirs[0], "codeql-extractor.yml");
 
-// Step 4: Update the built-in languages file.
-const content = `${JSON.stringify({ languages, aliases }, null, 2)}\n`;
-fs.mkdirSync(path.dirname(BUILTIN_LANGUAGES_FILE), { recursive: true });
-fs.writeFileSync(BUILTIN_LANGUAGES_FILE, content);
+    if (!fs.existsSync(extractorYmlPath)) {
+      throw new Error(
+        `Extractor YAML not found for language '${language}' at expected path: ${extractorYmlPath}`,
+      );
+    }
 
-console.log(`\nWrote ${BUILTIN_LANGUAGES_FILE}`);
-console.log(`  Languages: ${languages.join(", ")}`);
-console.log(`  Aliases: ${Object.keys(aliases).join(", ")}`);
+    const extractorYml = yaml.parse(fs.readFileSync(extractorYmlPath, "utf8"));
+    const defaultQueries: unknown[] | undefined = extractorYml.default_queries;
+
+    if (Array.isArray(defaultQueries) && defaultQueries.length > 0) {
+      console.log(
+        `  ✅ ${language}: included (default queries: ${JSON.stringify(defaultQueries)})`,
+      );
+      languages.push(language);
+    } else {
+      console.log(`  ❌ ${language}: excluded (no default queries)`);
+    }
+  }
+
+  return languages.sort();
+}
+
+/**
+ * Resolve language aliases from the CodeQL CLI, keeping only those whose
+ * target is in the given set of included languages.
+ */
+function resolveAliases(
+  codeqlPath: string,
+  includedLanguages: Set<string>,
+): Record<string, string> {
+  const betterjsonOutput = JSON.parse(
+    execFileSync(
+      codeqlPath,
+      [
+        "resolve",
+        "languages",
+        "--format=betterjson",
+        "--extractor-include-aliases",
+      ],
+      { encoding: "utf8" },
+    ),
+  );
+
+  return Object.fromEntries(
+    Object.entries((betterjsonOutput.aliases ?? {}) as Record<string, string>)
+      .filter(([, target]) => includedLanguages.has(target))
+      .sort(([a], [b]) => a.localeCompare(b)),
+  );
+}
+
+/** Write the built-in languages data to disk. */
+function writeBuiltinLanguages(
+  languages: string[],
+  aliases: Record<string, string>,
+): void {
+  const content = `${JSON.stringify({ languages, aliases }, null, 2)}\n`;
+  fs.mkdirSync(path.dirname(BUILTIN_LANGUAGES_FILE), { recursive: true });
+  fs.writeFileSync(BUILTIN_LANGUAGES_FILE, content);
+
+  console.log(`\nWrote ${BUILTIN_LANGUAGES_FILE}`);
+  console.log(`  Languages: ${languages.join(", ")}`);
+  console.log(`  Aliases: ${Object.keys(aliases).join(", ")}`);
+}
+
+function main(): void {
+  const codeqlPath = process.argv[2] || "codeql";
+
+  const extractorDirs = resolveLanguages(codeqlPath);
+  const languages = findLanguagesWithDefaultQueries(extractorDirs);
+  const aliases = resolveAliases(codeqlPath, new Set(languages));
+  writeBuiltinLanguages(languages, aliases);
+}
+
+main();