deno: add updateScript for automatic updates

This'll save time and avoid human error.
Wrote in deno typescript because why not.

pkgs/development/web/deno/update/common.ts

@@ -0,0 +1,52 @@
+interface GHRelease {
+  tag_name: string;
+}
+
+const decode = (buffer: Uint8Array) => new TextDecoder("utf-8").decode(buffer);
+const run = async (command: string, args: string[]) => {
+  const cmd = Deno.run(
+    { cmd: [command, ...args], stdout: "piped", stderr: "piped" },
+  );
+  if (!(await cmd.status()).success) {
+    throw await cmd.stderrOutput().then((b) => decode(b));
+  }
+  return cmd.output().then((b) => decode(b).trimEnd());
+};
+
+// Exports
+export const versionRegExp = /\d+\.\d+\.\d+/;
+export const sha256RegExp = /[a-z0-9]{52}/;
+
+export async function commit(
+  name: string,
+  oldVer: string,
+  newVer: string,
+  files: string[],
+) {
+  await run("git", ["add", ...files]);
+  await run("git", ["commit", "-m", `${name}: ${oldVer} -> ${newVer}`]);
+}
+
+export const getExistingVersion = async (filePath: string) =>
+  read(filePath).then((s) =>
+    s.match(genValueRegExp("version", versionRegExp))?.shift() || ""
+  );
+
+export const getLatestVersion = (owner: string, repo: string) =>
+  fetch(`https://api.github.com/repos/${owner}/${repo}/releases`)
+    .then((res) => res.json())
+    .then((res: GHRelease[]) => res[0].tag_name);
+
+// The (?<=) and (?=) allow replace to only change inside
+// Match the regex passed in or empty
+export const genValueRegExp = (key: string, regex: RegExp) =>
+  new RegExp(`(?<=${key} = ")(${regex.source}|)(?=")`);
+
+export const logger = (name: string) =>
+  (...a: any) => console.log(`[${name}]`, ...a);
+
+export const nixPrefetch = (args: string[]) => run("nix-prefetch", args);
+export const nixPrefetchURL = (args: string[]) => run("nix-prefetch-url", args);
+
+export const read = Deno.readTextFile;
+export const write = Deno.writeTextFile;