fix: generate correct type for arrays of objects (#706)

src/utils/typescript.ts

@@ -1,38 +1,54 @@
 import * as ts from 'typescript';
 
+const convertArrayItemToType = async (item: any): Promise<ts.TypeNode> => {
+  if (Array.isArray(item)) {
+    const nestedArrayItemTypes = await Promise.all(
+      item.map((nestedItem) => convertArrayItemToType(nestedItem)),
+    );
+    return ts.factory.createTupleTypeNode(nestedArrayItemTypes);
+  }
+  if (typeof item === 'object') {
+    return ts.factory.createTypeLiteralNode(
+      await convertObjectToTypeDefinition(item),
+    );
+  }
+  return ts.factory.createKeywordTypeNode(ts.SyntaxKind.StringKeyword);
+};
+
 export const convertObjectToTypeDefinition = async (
   object: any,
 ): Promise<ts.TypeElement[]> => {
   switch (typeof object) {
     case 'object':
       return Promise.all(
         Object.keys(object).map(async (key) => {
-          if (typeof object[key] === 'string') {
+          const value = object[key];
+
+          if (typeof value === 'string') {
             return ts.factory.createPropertySignature(
               undefined,
               ts.factory.createStringLiteral(key),
               undefined,
               ts.factory.createKeywordTypeNode(ts.SyntaxKind.StringKeyword),
             );
           }
-          if (Array.isArray(object[key])) {
+          if (Array.isArray(value)) {
+            const arrayItemTypes = await Promise.all(
+              value.map((item) => convertArrayItemToType(item)),
+            );
             return ts.factory.createPropertySignature(
               undefined,
               ts.factory.createStringLiteral(key),
               undefined,
-              ts.factory.createTupleTypeNode(
-                Array(object[key].length).fill(
-                  ts.factory.createKeywordTypeNode(ts.SyntaxKind.StringKeyword),
-                ),
-              ),
+              ts.factory.createTupleTypeNode(arrayItemTypes),
             );
           }
           return ts.factory.createPropertySignature(
             undefined,
             ts.factory.createStringLiteral(key),
             undefined,
             ts.factory.createTypeLiteralNode(
-              await convertObjectToTypeDefinition(object[key]),
+              await convertObjectToTypeDefinition(value),
             ),
           );
         }),

tests/generated/i18n.generated.ts

@@ -17,6 +17,20 @@ export type I18nTranslations = {
             string,
             string
         ];
+        "OBJECTS_ARRAY": [
+            {
+                "instructions": string;
+            },
+            {
+                "nestedArrayInstructions": [
+                    [
+                        {
+                            "instructions": string;
+                        }
+                    ]
+                ];
+            }
+        ];
         "cat": string;
         "ONLY_EN_KEY": string;
         "cat_name": string;

tests/i18n.spec.ts

@@ -76,6 +76,36 @@ describe('i18n module', () => {
     expect(i18nService.translate('test.ARRAY.2', { lang: 'nl' })).toBe('DRIE');
   });
 
+  it('i18n service should return objects array translation', () => {
+    expect(
+      i18nService.translate('test.OBJECTS_ARRAY.0.instructions', {
+        lang: 'en',
+      }),
+    ).toBe('Please follow the link');
+    expect(
+      i18nService.translate(
+        'test.OBJECTS_ARRAY.1.nestedArrayInstructions.0.0.instructions',
+        {
+          lang: 'en',
+        },
+      ),
+    ).toBe('Please try again');
+
+    expect(
+      i18nService.translate('test.OBJECTS_ARRAY.0.instructions', {
+        lang: 'uk',
+      }),
+    ).toBe('Будь ласка, перейдіть за посиланням');
+    expect(
+      i18nService.translate(
+        'test.OBJECTS_ARRAY.1.nestedArrayInstructions.0.0.instructions',
+        {
+          lang: 'uk',
+        },
+      ),
+    ).toBe('Будь ласка, спробуйте ще раз');
+  });
+
   it('i18n service should return fallback translation', () => {
     expect(i18nService.translate('test.ENGLISH', { lang: 'nl' })).toBe(
       'English',

tests/i18n/en/test.json

@@ -5,6 +5,12 @@
   },
   "ENGLISH": "English",
   "ARRAY": ["ONE", "TWO", "THREE"],
+  "OBJECTS_ARRAY": [
+    { "instructions": "Please follow the link" },
+    {
+      "nestedArrayInstructions": [[{ "instructions": "Please try again" }]]
+    }
+  ],
   "cat": "Cat",
   "ONLY_EN_KEY": "this key only exists in en lang",
   "cat_name": "Cat: {name}",

tests/i18n/uk/test.json

@@ -1,4 +1,12 @@
 {
+  "OBJECTS_ARRAY": [
+    { "instructions": "Будь ласка, перейдіть за посиланням" },
+    {
+      "nestedArrayInstructions": [
+        [{ "instructions": "Будь ласка, спробуйте ще раз" }]
+      ]
+    }
+  ],
   "day_interval": {
     "one": "{count} день",
     "few": "{count} дні",