1 files changed, 53 insertions, 0 deletions
diff --git a/.github/scripts/utils.mjs b/.github/scripts/utils.mjs
new file mode 100644
index 000000000..768302230
--- /dev/null
+++ b/.github/scripts/utils.mjs
@@ -0,0 +1,53 @@
+import * as crypto from 'node:crypto';
+import * as fs from 'node:fs';
+import * as os from 'node:os';
+
+/** Based on https://github.com/actions/toolkit/blob/4e3b068ce116d28cb840033c02f912100b4592b0/packages/core/src/file-command.ts */
+export function setOutput(key, value) {
+	const filePath = process.env['GITHUB_OUTPUT'] || '';
+	if (filePath) {
+		return issueFileCommand('OUTPUT', prepareKeyValueMessage(key, value));
+	}
+	process.stdout.write(os.EOL);
+}
+
+function issueFileCommand(command, message) {
+	const filePath = process.env[`GITHUB_${command}`];
+	if (!filePath) {
+		throw new Error(`Unable to find environment variable for file command ${command}`);
+	}
+	if (!fs.existsSync(filePath)) {
+		throw new Error(`Missing file at path: ${filePath}`);
+	}
+
+	fs.appendFileSync(filePath, `${toCommandValue(message)}${os.EOL}`, {
+		encoding: 'utf8',
+	});
+}
+
+function prepareKeyValueMessage(key, value) {
+	const delimiter = `gh-delimiter-${crypto.randomUUID()}`;
+	const convertedValue = toCommandValue(value);
+
+	// These should realistically never happen, but just in case someone finds a
+	// way to exploit uuid generation let's not allow keys or values that contain
+	// the delimiter.
+	if (key.includes(delimiter)) {
+		throw new Error(`Unexpected input: name should not contain the delimiter "${delimiter}"`);
+	}
+
+	if (convertedValue.includes(delimiter)) {
+		throw new Error(`Unexpected input: value should not contain the delimiter "${delimiter}"`);
+	}
+
+	return `${key}<<${delimiter}${os.EOL}${convertedValue}${os.EOL}${delimiter}`;
+}
+
+function toCommandValue(input) {
+	if (input === null || input === undefined) {
+		return '';
+	} else if (typeof input === 'string' || input instanceof String) {
+		return input;
+	}
+	return JSON.stringify(input);
+}