Merge pull request #373 from toddtarsi/handle-sparse-arrays

add handling for sparse arrays

src/__tests__/array/array.ts

@@ -2,6 +2,7 @@ import { existsSync, readFileSync, rmdirSync } from 'fs';
 import Joi from 'joi';
 
 import { convertFromDirectory, convertSchema } from '../../index';
+import { SparseTestListSchema } from './schemas/OneSparseSchema';
 
 describe('Array types', () => {
   const typeOutputDirectory = './src/__tests__/array/interfaces';
@@ -70,4 +71,13 @@ export type TestList = Test[];
  */
 export type TestList = string[];`);
   });
+
+  test('test to ensure sparse arrays have undefined as a possible type', () => {
+    const result = convertSchema({ sortPropertiesByName: true }, SparseTestListSchema);
+    expect(result).not.toBeUndefined;
+    expect(result?.content).toBe(`/**
+ * A sparse list of Item object
+ */
+export type SparseTestList = (Item | undefined)[];`);
+  });
 });

src/__tests__/array/schemas/OneSparseSchema.ts

@@ -0,0 +1,8 @@
+import Joi from 'joi';
+import {ItemSchema} from './OneSchema'
+
+export const SparseTestListSchema = Joi.array()
+  .items(ItemSchema)
+  .sparse()
+  .meta({ className: 'SparseTestList' })
+  .description('A sparse list of Item object');

src/joiDescribeTypes.ts

@@ -29,6 +29,10 @@ export interface BaseDescribe extends Joi.Description {
      * Default object value
      */
     default?: unknown;
+    /**
+     * Allow undefined values in array
+     */
+    sparse?: boolean;
     /**
      * https://joi.dev/api/#objectunknownallow
      */

src/parse.ts

@@ -410,6 +410,7 @@ function parseStringSchema(details: StringDescribe, settings: Settings, rootSche
 
 function parseArray(details: ArrayDescribe, settings: Settings): TypeContent | undefined {
   const { interfaceOrTypeName, jsDoc } = getCommonDetails(details, settings);
+  const isSparse = details.flags?.sparse;
 
   if (details.ordered && !details.items) {
     const parsedChildren = details.ordered.map(item => parseSchema(item, settings)).filter(Boolean) as TypeContent[];
@@ -439,7 +440,6 @@ function parseArray(details: ArrayDescribe, settings: Settings): TypeContent | u
 
   // TODO: handle multiple things in the items arr
   const item = details.items && !details.ordered ? details.items[0] : ({ type: 'any' } as Describe);
-
   const child = parseSchema(item, settings);
   if (!child) {
     return undefined;
@@ -454,6 +454,21 @@ function parseArray(details: ArrayDescribe, settings: Settings): TypeContent | u
 
     return makeTypeContentRoot({ joinOperation: 'union', children: allowedValues, interfaceOrTypeName, jsDoc });
   }
+  if (isSparse) {
+    return makeTypeContentRoot({
+      joinOperation: 'list',
+      children: [
+        makeTypeContentRoot({
+          joinOperation: 'union',
+          children: [child, makeTypeContentChild({ content: 'undefined' })],
+          interfaceOrTypeName,
+          jsDoc
+        })
+      ],
+      interfaceOrTypeName,
+      jsDoc
+    });
+  }
 
   return makeTypeContentRoot({ joinOperation: 'list', children: [child], interfaceOrTypeName, jsDoc });
 }
@@ -481,7 +496,7 @@ function parseAlternatives(details: AlternativesDescribe, settings: Settings): T
     joinOperation: 'union',
     children: [...children, ...allowedValues],
     interfaceOrTypeName,
-    jsDoc,
+    jsDoc
   });
 }