Procedural SafeCast.sol generation (#3245)

scripts/generate/run.js

@@ -0,0 +1,29 @@
+#!/usr/bin/env node
+
+const fs = require('fs');
+const format = require('./format-lines');
+
+function getVersion (path) {
+  try {
+    return fs
+      .readFileSync(path, 'utf8')
+      .match(/\/\/ OpenZeppelin Contracts \(last updated v\d+\.\d+\.\d+\)/)[0];
+  } catch (err) {
+    return null;
+  }
+}
+
+for (const [ file, template ] of Object.entries({
+  'utils/math/SafeCast.sol': './templates/SafeCast',
+  'mocks/SafeCastMock.sol': './templates/SafeCastMock',
+})) {
+  const path = `./contracts/${file}`;
+  const version = getVersion(path);
+  const content = format(
+    '// SPDX-License-Identifier: MIT',
+    (version ? version + ` (${file})\n` : ''),
+    require(template).trimEnd(),
+  );
+
+  fs.writeFileSync(path, content);
+}