fix: throw duplicate error on extraction

Author: jquense

packages/babel-preset/intl-preset.js

@@ -3,6 +3,30 @@ const path = require('path');
 
 const { interpolateName } = require('@formatjs/ts-transformer');
 const intlPlugin = require('babel-plugin-formatjs').default;
+const stringify = require('fast-json-stable-stringify');
+
+function mergeDuplicates(messages) {
+  const seen = new Map();
+
+  return messages.filter((message) => {
+    const other = seen.get(message.id);
+
+    seen.set(message.id, message);
+
+    if (!other) return true;
+
+    if (
+      stringify(message.description) !== stringify(other.description) ||
+      message.defaultMessage !== other.defaultMessage
+    ) {
+      throw new Error(
+        `Duplicate message id: "${message.id}", but the \`description\` and/or \`defaultMessage\` are different.`,
+      );
+    }
+    // if they are the same, filter this one out
+    return false;
+  });
+}
 
 module.exports = function intlPreset(_, options = {}) {
   const {
@@ -56,6 +80,8 @@ module.exports = function intlPreset(_, options = {}) {
 
             mkdirSync(path.join(messagesDir, dir), { recursive: true });
 
+            messages = mergeDuplicates(messages);
+
             writeFileSync(
               path.join(messagesDir, dir, `${name}.json`),
               JSON.stringify(messages, null, 2),

packages/babel-preset/package.json

@@ -37,6 +37,7 @@
     "babel-plugin-formatjs": "^10.3.25",
     "babel-plugin-polyfill-corejs3": "^0.5.3",
     "browserslist": "^4.21.3",
+    "fast-json-stable-stringify": "^2.1.0",
     "lodash": "^4.17.21"
   },
   "devDependencies": {

yarn.lock

@@ -21,15 +21,6 @@
     text-table "^0.2.0"
     yargs "^17.1.1"
 
-"@4c/jest-preset@^1.8.0":
-  version "1.8.0"
-  resolved "https://registry.yarnpkg.com/@4c/jest-preset/-/jest-preset-1.8.0.tgz#79e1fa5dfefa642808c6d65ab7908ea4e9394ec6"
-  integrity sha512-qBrBrbR/YiOleNJErwaMqCP+cw4YGqXF3R+EIgLg/La28sf9fuhCaYjN9OrUBLjKwF6HkdMfPrd7M0iSV9NPHA==
-  dependencies:
-    babel-jest "^28.1.3"
-    find-up "^5.0.0"
-    find-yarn-workspace-root "^2.0.0"
-
 "@ampproject/remapping@^2.1.0":
   version "2.2.0"
   resolved "https://registry.yarnpkg.com/@ampproject/remapping/-/remapping-2.2.0.tgz#56c133824780de3174aed5ab6834f3026790154d"
@@ -4626,7 +4617,7 @@ fast-glob@^3.2.9:
     merge2 "^1.3.0"
     micromatch "^4.0.4"
 
-fast-json-stable-stringify@^2.0.0:
+fast-json-stable-stringify@^2.0.0, fast-json-stable-stringify@^2.1.0:
   version "2.1.0"
   resolved "https://registry.yarnpkg.com/fast-json-stable-stringify/-/fast-json-stable-stringify-2.1.0.tgz#874bf69c6f404c2b5d99c481341399fd55892633"
   integrity sha512-lhd/wF+Lk98HZoTCtlVraHtfh5XYijIjalXck7saUtuanSDyLMxnHhSXEDJqHxD7msR8D0uCmqlkwjCV8xvwHw==