fix: resolve validation types circular reference in loaders

Fixes TypeScript error when using validation types in createFileRoute loaders.
Replaced Constrain with conditional types to prevent circular references.

- Fix ValidateLinkOptions, ValidateNavigateOptions, ValidateRedirectOptions
- Add comprehensive regression tests
- Maintain backward compatibility

Author: swarnim02

packages/react-router/src/typePrimitives.ts

@@ -19,17 +19,23 @@ export type ValidateLinkOptions<
   TOptions = unknown,
   TDefaultFrom extends string = string,
   TComp = 'a',
-> = Constrain<
-  TOptions,
-  LinkComponentProps<
-    TComp,
-    TRouter,
-    InferFrom<TOptions, TDefaultFrom>,
-    InferTo<TOptions>,
-    InferMaskFrom<TOptions>,
-    InferMaskTo<TOptions>
-  >
+> = TOptions extends LinkComponentProps<
+  TComp,
+  TRouter,
+  InferFrom<TOptions, TDefaultFrom>,
+  InferTo<TOptions>,
+  InferMaskFrom<TOptions>,
+  InferMaskTo<TOptions>
 >
+  ? TOptions
+  : LinkComponentProps<
+      TComp,
+      TRouter,
+      InferFrom<TOptions, TDefaultFrom>,
+      InferTo<TOptions>,
+      InferMaskFrom<TOptions>,
+      InferMaskTo<TOptions>
+    >
 
 /**
  * @private
@@ -43,32 +49,44 @@ export type InferStructuralSharing<TOptions> = TOptions extends {
 export type ValidateUseSearchOptions<
   TOptions,
   TRouter extends AnyRouter = RegisteredRouter,
-> = Constrain<
-  TOptions,
-  UseSearchOptions<
-    TRouter,
-    InferFrom<TOptions>,
-    InferStrict<TOptions>,
-    InferShouldThrow<TOptions>,
-    InferSelected<TOptions>,
-    InferStructuralSharing<TOptions>
-  >
+> = TOptions extends UseSearchOptions<
+  TRouter,
+  InferFrom<TOptions>,
+  InferStrict<TOptions>,
+  InferShouldThrow<TOptions>,
+  InferSelected<TOptions>,
+  InferStructuralSharing<TOptions>
 >
+  ? TOptions
+  : UseSearchOptions<
+      TRouter,
+      InferFrom<TOptions>,
+      InferStrict<TOptions>,
+      InferShouldThrow<TOptions>,
+      InferSelected<TOptions>,
+      InferStructuralSharing<TOptions>
+    >
 
 export type ValidateUseParamsOptions<
   TOptions,
   TRouter extends AnyRouter = RegisteredRouter,
-> = Constrain<
-  TOptions,
-  UseParamsOptions<
-    TRouter,
-    InferFrom<TOptions>,
-    InferStrict<TOptions>,
-    InferShouldThrow<TOptions>,
-    InferSelected<TOptions>,
-    InferSelected<TOptions>
-  >
+> = TOptions extends UseParamsOptions<
+  TRouter,
+  InferFrom<TOptions>,
+  InferStrict<TOptions>,
+  InferShouldThrow<TOptions>,
+  InferSelected<TOptions>,
+  InferSelected<TOptions>
 >
+  ? TOptions
+  : UseParamsOptions<
+      TRouter,
+      InferFrom<TOptions>,
+      InferStrict<TOptions>,
+      InferShouldThrow<TOptions>,
+      InferSelected<TOptions>,
+      InferSelected<TOptions>
+    >
 export type ValidateLinkOptionsArray<
   TRouter extends AnyRouter = RegisteredRouter,
   TOptions extends ReadonlyArray<any> = ReadonlyArray<unknown>,

packages/react-router/tests/validateLinkOptions.test.tsx

@@ -0,0 +1,139 @@
+import { describe, expect, test } from 'vitest'
+import { createFileRoute } from '../src/fileRoute'
+import type { 
+  ValidateLinkOptions, 
+  ValidateUseSearchOptions, 
+  ValidateUseParamsOptions 
+} from '../src/typePrimitives'
+import type { 
+  ValidateNavigateOptions, 
+  ValidateRedirectOptions 
+} from '@tanstack/router-core'
+
+describe('Validation types regression tests', () => {
+  test('should not cause TypeScript circular reference error in loader return type', () => {
+    // This test ensures that ValidateLinkOptions can be used in loader return types
+    // without causing the TypeScript error:
+    // 'loader' implicitly has return type 'any' because it does not have a return type annotation
+    
+    const route = createFileRoute('/user/$userId')({
+      loader: (): { breadcrumbs: ValidateLinkOptions } => {
+        const breadcrumbs: ValidateLinkOptions = {
+          to: '/user/$userId',
+          params: { userId: '123' }
+        }
+        
+        return {
+          breadcrumbs
+        }
+      },
+      component: () => <div>User</div>
+    })
+
+    expect(route).toBeDefined()
+  })
+
+  test('should work with ValidateLinkOptions directly in loader', () => {
+    const route = createFileRoute('/profile/$userId')({
+      loader: () => {
+        const linkOptions: ValidateLinkOptions = {
+          to: '/profile/$userId',
+          params: { userId: '456' }
+        }
+        
+        return {
+          navigation: linkOptions
+        }
+      },
+      component: () => <div>Profile</div>
+    })
+
+    expect(route).toBeDefined()
+  })
+
+  test('should work with array of ValidateLinkOptions', () => {
+    const route = createFileRoute('/dashboard')({
+      loader: () => {
+        const breadcrumbs: ValidateLinkOptions[] = [
+          { to: '/' },
+          { to: '/dashboard' }
+        ]
+        
+        return {
+          breadcrumbs
+        }
+      },
+      component: () => <div>Dashboard</div>
+    })
+
+    expect(route).toBeDefined()
+  })
+
+  test('should work with ValidateNavigateOptions in loader', () => {
+    const route = createFileRoute('/navigate-test')({  
+      loader: () => {
+        const navOptions: ValidateNavigateOptions = {
+          to: '/dashboard'
+        }
+        
+        return {
+          navOptions
+        }
+      },
+      component: () => <div>Navigate Test</div>
+    })
+
+    expect(route).toBeDefined()
+  })
+
+  test('should work with ValidateRedirectOptions in loader', () => {
+    const route = createFileRoute('/redirect-test')({  
+      loader: () => {
+        const redirectOptions: ValidateRedirectOptions = {
+          to: '/login'
+        }
+        
+        return {
+          redirectOptions
+        }
+      },
+      component: () => <div>Redirect Test</div>
+    })
+
+    expect(route).toBeDefined()
+  })
+
+  test('should work with ValidateUseSearchOptions in loader', () => {
+    const route = createFileRoute('/search-test')({  
+      loader: () => {
+        const searchOptions: ValidateUseSearchOptions<{ from: '/search-test' }> = {
+          from: '/search-test'
+        }
+        
+        return {
+          searchOptions
+        }
+      },
+      component: () => <div>Search Test</div>
+    })
+
+    expect(route).toBeDefined()
+  })
+
+  test('should work with ValidateUseParamsOptions in loader', () => {
+    const route = createFileRoute('/params-test/$id')({  
+      loader: () => {
+        const paramsOptions: ValidateUseParamsOptions<{ from: '/params-test/$id' }> = {
+          from: '/params-test/$id'
+        }
+        
+        return {
+          paramsOptions
+        }
+      },
+      component: () => <div>Params Test</div>
+    })
+
+    expect(route).toBeDefined()
+  })
+})

packages/router-core/src/typePrimitives.ts

@@ -75,16 +75,21 @@ export type ValidateNavigateOptions<
   TRouter extends AnyRouter = RegisteredRouter,
   TOptions = unknown,
   TDefaultFrom extends string = string,
-> = Constrain<
-  TOptions,
-  NavigateOptions<
-    TRouter,
-    InferFrom<TOptions, TDefaultFrom>,
-    InferTo<TOptions>,
-    InferMaskFrom<TOptions>,
-    InferMaskTo<TOptions>
-  >
+> = TOptions extends NavigateOptions<
+  TRouter,
+  InferFrom<TOptions, TDefaultFrom>,
+  InferTo<TOptions>,
+  InferMaskFrom<TOptions>,
+  InferMaskTo<TOptions>
 >
+  ? TOptions
+  : NavigateOptions<
+      TRouter,
+      InferFrom<TOptions, TDefaultFrom>,
+      InferTo<TOptions>,
+      InferMaskFrom<TOptions>,
+      InferMaskTo<TOptions>
+    >
 
 export type ValidateNavigateOptionsArray<
   TRouter extends AnyRouter = RegisteredRouter,
@@ -102,16 +107,21 @@ export type ValidateRedirectOptions<
   TRouter extends AnyRouter = RegisteredRouter,
   TOptions = unknown,
   TDefaultFrom extends string = string,
-> = Constrain<
-  TOptions,
-  RedirectOptions<
-    TRouter,
-    InferFrom<TOptions, TDefaultFrom>,
-    InferTo<TOptions>,
-    InferMaskFrom<TOptions>,
-    InferMaskTo<TOptions>
-  >
+> = TOptions extends RedirectOptions<
+  TRouter,
+  InferFrom<TOptions, TDefaultFrom>,
+  InferTo<TOptions>,
+  InferMaskFrom<TOptions>,
+  InferMaskTo<TOptions>
 >
+  ? TOptions
+  : RedirectOptions<
+      TRouter,
+      InferFrom<TOptions, TDefaultFrom>,
+      InferTo<TOptions>,
+      InferMaskFrom<TOptions>,
+      InferMaskTo<TOptions>
+    >
 
 export type ValidateRedirectOptionsArray<
   TRouter extends AnyRouter = RegisteredRouter,
@@ -170,12 +180,16 @@ export type ValidateUseSearchResult<
 export type ValidateUseParamsResult<
   TOptions,
   TRouter extends AnyRouter = RegisteredRouter,
-> = Constrain<
-  TOptions,
-  UseParamsResult<
-    TRouter,
-    InferFrom<TOptions>,
-    InferStrict<TOptions>,
-    InferSelected<TOptions>
-  >
+> = TOptions extends UseParamsResult<
+  TRouter,
+  InferFrom<TOptions>,
+  InferStrict<TOptions>,
+  InferSelected<TOptions>
 >
+  ? TOptions
+  : UseParamsResult<
+      TRouter,
+      InferFrom<TOptions>,
+      InferStrict<TOptions>,
+      InferSelected<TOptions>
+    >