feat(generators): splicePluginRulesAt + splicePluginImportsAt + addBoundariesEntry + emitTemplateTree helpers

turbo/generators/lib/core-package-utils.ts

@@ -1,5 +1,10 @@
-import { existsSync, readFileSync, writeFileSync } from "node:fs";
-import { join } from "node:path";
+import { existsSync, readFileSync, writeFileSync, readdirSync, statSync } from "node:fs";
+import { join, relative, dirname } from "node:path";
+import type { PlopTypes } from "@turbo/gen";
+import { fileURLToPath } from "node:url";
+
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = dirname(__filename);
 
 /**
  * Throws if a core package directory already exists. Used as the first action
@@ -42,3 +47,104 @@ export function addToTranspilePackages(
   );
   writeFileSync(nextConfigPath, updated);
 }
+
+/**
+ * Inserts a code block immediately after a `// <gen:NAME>` anchor in a file.
+ * Idempotent: refuses to insert if the exact block already follows the anchor.
+ */
+export function splicePluginRulesAt(
+  filePath: string,
+  anchorName: string,
+  block: string,
+): void {
+  const source = readFileSync(filePath, "utf8");
+  const anchor = `// <gen:${anchorName}>`;
+  const idx = source.indexOf(anchor);
+  if (idx === -1) {
+    throw new Error(`Anchor ${anchor} not found in ${filePath}`);
+  }
+  const after = source.slice(idx + anchor.length);
+  if (after.trimStart().startsWith(block.trim())) return; // idempotent
+  const updated =
+    source.slice(0, idx + anchor.length) + "\n" + block + after;
+  writeFileSync(filePath, updated);
+}
+
+/**
+ * Inserts an import line immediately after the matching anchor. Idempotent.
+ */
+export function splicePluginImportsAt(
+  filePath: string,
+  anchorName: string,
+  importLine: string,
+): void {
+  splicePluginRulesAt(filePath, anchorName, importLine);
+}
+
+/**
+ * Inserts a `{ type, pattern, ...opts }` entry into the boundaries/elements
+ * array of `core-eslint/base.js`, placed immediately BEFORE the
+ * `packages/core-*` wildcard so its more-specific match wins. Idempotent.
+ */
+export function addBoundariesEntry(
+  baseJsPath: string,
+  packagePath: string,
+  opts: { mode?: "folder" } = {},
+): void {
+  const source = readFileSync(baseJsPath, "utf8");
+  if (source.includes(`pattern: "${packagePath}"`)) return; // idempotent
+  const wildcardLine = source.match(
+    /(\s*\{\s*type:\s*"core",\s*pattern:\s*"packages\/core-\*"[^}]*\},)/,
+  );
+  if (!wildcardLine) {
+    throw new Error(`packages/core-* wildcard not found in ${baseJsPath}`);
+  }
+  const modeFragment = opts.mode ? `, mode: "${opts.mode}"` : "";
+  const newEntry = `        { type: "core", pattern: "${packagePath}"${modeFragment} },\n`;
+  const updated = source.replace(wildcardLine[0], `\n${newEntry}${wildcardLine[1]}`);
+  writeFileSync(baseJsPath, updated);
+}
+
+/**
+ * Walks turbo/generators/templates/<srcPrefix>/ recursively. For each .hbs
+ * file, returns a plop `add` action that emits the file (without .hbs
+ * extension) at <destPrefix>/<relative-path>. The actions are sorted so
+ * directory creation is deterministic.
+ */
+export function emitTemplateTree(
+  srcPrefix: string,
+  destPrefix: string,
+  opts: { templatesRoot?: string } = {},
+): PlopTypes.AddActionConfig[] {
+  const root =
+    opts.templatesRoot ?? join(__dirname, "..", "templates");
+  const srcRoot = join(root, srcPrefix);
+  const out: PlopTypes.AddActionConfig[] = [];
+  walkHbs(srcRoot, srcRoot, srcPrefix, destPrefix, out);
+  out.sort((a, b) => (a.path ?? "").localeCompare(b.path ?? ""));
+  return out;
+}
+
+function walkHbs(
+  topRoot: string,
+  dir: string,
+  srcPrefix: string,
+  destPrefix: string,
+  out: PlopTypes.AddActionConfig[],
+): void {
+  for (const name of readdirSync(dir)) {
+    const full = join(dir, name);
+    if (statSync(full).isDirectory()) {
+      walkHbs(topRoot, full, srcPrefix, destPrefix, out);
+      continue;
+    }
+    if (!name.endsWith(".hbs")) continue;
+    const rel = relative(topRoot, full).replace(/\.hbs$/, "");
+    out.push({
+      type: "add",
+      path: join(destPrefix, rel).replace(/\\/g, "/"),
+      templateFile: join("templates", srcPrefix, relative(topRoot, full)).replace(/\\/g, "/"),
+    } as PlopTypes.AddActionConfig);
+  }
+}
+