[Tools] Validate values in nested ICU messages

src/dev/i18n/__snapshots__/utils.test.js.snap

@@ -35,3 +35,8 @@ exports[`i18n utils should throw if some key is missing in "values" 1`] = `
 "some properties are missing in \\"values\\" object (\\"namespace.message.id\\"):
 [password]."
 `;
+
+exports[`i18n utils should throw on wrong nested ICU message 1`] = `
+"\\"values\\" object contains unused properties (\\"namespace.message.id\\"):
+[third]."
+`;

src/dev/i18n/utils.js

@@ -38,6 +38,8 @@ import { createFailError } from '../run';
 const ESCAPE_LINE_BREAK_REGEX = /(?<!\\)\\\n/g;
 const HTML_LINE_BREAK_REGEX = /[\s]*\n[\s]*/g;
 
+const ARGUMENT_ELEMENT_TYPE = 'argumentElement';
+
 export const readFileAsync = promisify(fs.readFile);
 export const writeFileAsync = promisify(fs.writeFile);
 export const globAsync = promisify(glob);
@@ -125,6 +127,32 @@ export function createParserErrorMessage(content, error) {
   return `${error.message}:\n${context}`;
 }
 
+/**
+ * Recursively extracts all references from ICU message ast.
+ *
+ * Example: `'Removed tag {tag} from {assignmentsLength, plural, one {beat {beatName}} other {# beats}}.'`
+ *
+ * @param {any} node
+ * @param {Set<string>} keys
+ */
+function extractValueReferencesFromIcuAst(node, keys = new Set()) {
+  if (Array.isArray(node.elements)) {
+    for (const element of node.elements.filter(element => element.type === ARGUMENT_ELEMENT_TYPE)) {
+      keys.add(element.id);
+
+      if (element.format && Array.isArray(element.format.options)) {
+        for (const option of element.format.options) {
+          extractValueReferencesFromIcuAst(option, keys);
+        }
+      }
+    }
+  } else if (node.value) {
+    extractValueReferencesFromIcuAst(node.value, keys);
+  }
+
+  return [...keys];
+}
+
 /**
  * Checks whether values from "values" and "defaultMessage" correspond to each other.
  *
@@ -161,19 +189,12 @@ export function checkValuesProperty(valuesKeys, defaultMessage, messageId) {
     throw error;
   }
 
-  const ARGUMENT_ELEMENT_TYPE = 'argumentElement';
-
   // skip validation if intl-messageformat-parser didn't return an AST with nonempty elements array
   if (!defaultMessageAst || !defaultMessageAst.elements || !defaultMessageAst.elements.length) {
     return;
   }
 
-  const defaultMessageValueReferences = defaultMessageAst.elements.reduce((keys, element) => {
-    if (element.type === ARGUMENT_ELEMENT_TYPE) {
-      keys.push(element.id);
-    }
-    return keys;
-  }, []);
+  const defaultMessageValueReferences = extractValueReferencesFromIcuAst(defaultMessageAst);
 
   const missingValuesKeys = difference(defaultMessageValueReferences, valuesKeys);
   if (missingValuesKeys.length) {

src/dev/i18n/utils.test.js

@@ -153,4 +153,24 @@ describe('i18n utils', () => {
       checkValuesProperty(valuesKeys, defaultMessage, messageId)
     ).toThrowErrorMatchingSnapshot();
   });
+
+  test('should parse nested ICU message', () => {
+    const valuesKeys = ['first', 'second', 'third'];
+    const defaultMessage = 'Test message {first, plural, one {{second}} other {{third}}}';
+    const messageId = 'namespace.message.id';
+
+    expect(() =>
+      checkValuesProperty(valuesKeys, defaultMessage, messageId)
+    ).not.toThrow();
+  });
+
+  test(`should throw on wrong nested ICU message`, () => {
+    const valuesKeys = ['first', 'second', 'third'];
+    const defaultMessage = 'Test message {first, plural, one {{second}} other {other}}';
+    const messageId = 'namespace.message.id';
+
+    expect(() =>
+      checkValuesProperty(valuesKeys, defaultMessage, messageId)
+    ).toThrowErrorMatchingSnapshot();
+  });
 });