Add changelog-for-patch script (#11052)

- Add ./scripts/changelog-for-patch.mjs
- Extract common functions to ./scripts/utils/changelog
- Use changelog-for-patch.mjs from release script

scripts/utils/changelog.mjs

@@ -0,0 +1,91 @@
+import fs from "node:fs";
+import path from "node:path";
+import createEsmUtils from "esm-utils";
+import semver from "semver";
+
+const { __dirname } = createEsmUtils(import.meta);
+
+export const changelogUnreleasedDirPath = path.join(
+  __dirname,
+  "../../changelog_unreleased"
+);
+
+export const changelogUnreleasedDirs = fs
+  .readdirSync(changelogUnreleasedDirPath, {
+    withFileTypes: true,
+  })
+  .filter((entry) => entry.isDirectory());
+
+export function getEntries(dirPath) {
+  const fileNames = fs
+    .readdirSync(dirPath)
+    .filter((fileName) => path.extname(fileName) === ".md");
+  const entries = fileNames.map((fileName) => {
+    const [title, ...rest] = fs
+      .readFileSync(path.join(dirPath, fileName), "utf8")
+      .trim()
+      .split("\n");
+
+    const improvement = title.match(/\[IMPROVEMENT(:(\d+))?]/);
+
+    const section = title.includes("[HIGHLIGHT]")
+      ? "highlight"
+      : title.includes("[BREAKING]")
+      ? "breaking"
+      : improvement
+      ? "improvement"
+      : undefined;
+
+    const order =
+      section === "improvement" && improvement[2] !== undefined
+        ? Number(improvement[2])
+        : undefined;
+
+    const content = [processTitle(title), ...rest].join("\n");
+
+    return { fileName, section, order, content };
+  });
+  return entries;
+}
+
+export function printEntries(entries) {
+  const result = [];
+  if (entries.length > 0) {
+    entries.sort((a, b) => {
+      if (a.order !== undefined) {
+        return b.order === undefined ? 1 : a.order - b.order;
+      }
+      return a.fileName.localeCompare(b.fileName, "en", { numeric: true });
+    });
+    result.push(...entries.map((entry) => entry.content));
+  }
+  return result;
+}
+
+export function replaceVersions(data, prevVer, newVer, isPatch = false) {
+  return data
+    .replace(
+      /prettier stable/gi,
+      `Prettier ${isPatch ? prevVer : formatVersion(prevVer)}`
+    )
+    .replace(
+      /prettier main/gi,
+      `Prettier ${isPatch ? newVer : formatVersion(newVer)}`
+    );
+}
+
+function formatVersion(version) {
+  return `${semver.major(version)}.${semver.minor(version)}`;
+}
+
+function processTitle(title) {
+  return title
+    .replace(/\[(BREAKING|HIGHLIGHT|IMPROVEMENT(:\d+)?)]/g, "")
+    .replace(/\s+/g, " ")
+    .replace(/^#{4} [a-z]/, (s) => s.toUpperCase())
+    .replace(/(?<![[`])@([\w-]+)/g, "[@$1](https://github.com/$1)")
+    .replace(
+      /(?<![[`])#(\d{4,})/g,
+      "[#$1](https://github.com/prettier/prettier/pull/$1)"
+    );
+}