Switch to Changesets-based release process (#118)

* Switch to Changesets-based release process

* Bump version

* drop unused variable

* Update .github/workflows/version-or-publish.yml

Co-authored-by: Nicola Molinari <nicola.molinari@commercetools.com>

* Push also to a release line branch when releasing

* Change node version used in the version-or-publish workflow

* Switch to using the local action

Co-authored-by: Nicola Molinari <nicola.molinari@commercetools.com>

* build the action before trying to use it the workflow

* Add changeset and actually setup Changesets, lol

Co-authored-by: Nicola Molinari <nicola.molinari@commercetools.com>

scripts/release.js

@@ -0,0 +1,41 @@
+const path = require("path");
+const { exec, getExecOutput } = require("@actions/exec");
+
+const { version } = require("../package.json");
+const tag = `v${version}`;
+const releaseLine = `v${version.split(".")[0]}`;
+
+process.chdir(path.join(__dirname, ".."));
+
+(async () => {
+  const { exitCode, stderr } = await getExecOutput(
+    `git`,
+    ["ls-remote", "--exit-code", "origin", "--tags", `refs/tags/${tag}`],
+    {
+      ignoreReturnCode: true,
+    }
+  );
+  if (exitCode === 0) {
+    console.log(
+      `Action is not being published because version ${tag} is already published`
+    );
+    return;
+  }
+  if (exitCode !== 2) {
+    throw new Error(`git ls-remote exited with ${exitCode}:\n${stderr}`);
+  }
+
+  await exec("git", ["checkout", "--detach"]);
+  await exec("git", ["add", "--force", "dist"]);
+  await exec("git", ["commit", "-m", tag]);
+
+  await exec("changeset", ["tag"]);
+
+  await exec("git", [
+    "push",
+    "--force",
+    "--follow-tags",
+    "origin",
+    `HEAD:refs/heads/${releaseLine}`,
+  ]);
+})();