feat: add tryValidate method

src/vine/validator.ts

@@ -12,6 +12,7 @@ import type { MessagesProviderContact, Refs, RootNode } from '@vinejs/compiler/t
 
 import { messages } from '../defaults.js'
 import { ITYPE, OTYPE, PARSE } from '../symbols.js'
+import { ValidationError } from '../errors/validation_error.js'
 import type {
   Infer,
   SchemaTypes,
@@ -158,6 +159,28 @@ export class VineValidator<
     }
   }
 
+  /**
+   * Performs validation without throwing the validation
+   * exception. Instead, the validation errors are
+   * returned as the first argument.
+   */
+  async tryValidate(
+    data: any,
+    ...[options]: [undefined] extends MetaData
+      ? [options?: ValidationOptions<MetaData> | undefined]
+      : [options: ValidationOptions<MetaData>]
+  ): Promise<[ValidationError, null] | [null, Infer<Schema>]> {
+    try {
+      const result = await this.validate(data, options!)
+      return [null, result]
+    } catch (error) {
+      if (error instanceof ValidationError) {
+        return [error, null]
+      }
+      throw error
+    }
+  }
+
   /**
    * Returns the compiled schema and refs.
    */

tests/integration/validator.spec.ts

@@ -20,6 +20,8 @@ import vine, {
   VineLiteral,
   VineBoolean,
 } from '../../index.js'
+import { Infer } from '../../src/types.js'
+import { ValidationError } from '../../src/errors/validation_error.js'
 
 test.group('Validator | metadata', () => {
   test('pass metadata to the validation pipeline', async ({ assert }) => {
@@ -314,3 +316,79 @@ test.group('Validator | toJSON', () => {
     `)
   })
 })
+
+test.group('Validator | tryValidator', () => {
+  test('return validation errors without throwing an exception', async ({
+    assert,
+    expectTypeOf,
+  }) => {
+    const author = vine.object({
+      name: vine.string(),
+      email: vine.string().email(),
+    })
+
+    const validator = vine.compile(author)
+    const [error, result] = await validator.tryValidate({})
+    assert.instanceOf(error, ValidationError)
+    assert.isNull(result)
+
+    if (error) {
+      expectTypeOf(result).toMatchTypeOf(null)
+      expectTypeOf(error).toMatchTypeOf<ValidationError>()
+    }
+    if (result) {
+      expectTypeOf(error).toMatchTypeOf(null)
+      expectTypeOf(result).toMatchTypeOf<Infer<typeof validator>>()
+    }
+  })
+
+  test('rethrow non ValidationError errors', async () => {
+    const author = vine.object({
+      name: vine.string(),
+      email: vine.string().email(),
+    })
+
+    const validator = vine
+      .withMetaData<{ choices: string[] }>(() => {
+        throw new Error('Invalid metadata')
+      })
+      .compile(author)
+
+    await validator.tryValidate(
+      {},
+      {
+        meta: {
+          choices: [],
+        },
+      }
+    )
+  }).throws('Invalid metadata')
+
+  test('return validated data', async ({ assert, expectTypeOf }) => {
+    const author = vine.object({
+      name: vine.string(),
+      email: vine.string().email(),
+    })
+
+    const validator = vine.compile(author)
+    const [error, result] = await validator.tryValidate({
+      name: 'virk',
+      email: '[email protected]',
+    })
+
+    assert.isNull(error)
+    assert.deepEqual(result, {
+      name: 'virk',
+      email: '[email protected]',
+    })
+
+    if (error) {
+      expectTypeOf(result).toMatchTypeOf(null)
+      expectTypeOf(error).toMatchTypeOf<ValidationError>()
+    }
+    if (result) {
+      expectTypeOf(error).toMatchTypeOf(null)
+      expectTypeOf(result).toMatchTypeOf<Infer<typeof validator>>()
+    }
+  })
+})