fix: resolve_route prevent dropping a trailing slash of id

Author: yuki0418

.changeset/every-kings-wink.md

@@ -0,0 +1,5 @@
+---
+'@sveltejs/kit': patch
+---
+
+fix: resolve_route prevent dropping a trailing slash of id

packages/kit/src/utils/routing.js

@@ -240,6 +240,8 @@ const basic_param_pattern = /\[(\[)?(\.\.\.)?(\w+?)(?:=(\w+))?\]\]?/g;
  */
 export function resolve_route(id, params) {
 	const segments = get_route_segments(id);
+	const has_id_trailing_slash = id != '/' && id.endsWith('/');
+
 	return (
 		'/' +
 		segments
@@ -262,7 +264,8 @@ export function resolve_route(id, params) {
 				})
 			)
 			.filter(Boolean)
-			.join('/')
+			.join('/') +
+		(has_id_trailing_slash ? '/' : '')
 	);
 }
 

packages/kit/src/utils/routing.spec.js

@@ -278,30 +278,60 @@ describe('resolve_route', () => {
 			params: { one: 'one', two: 'two' },
 			expected: '/blog/one/two'
 		},
+		{
+			route: '/blog/[one]/[two]/',
+			params: { one: 'one', two: 'two' },
+			expected: '/blog/one/two/'
+		},
 		{
 			route: '/blog/[one=matcher]/[...two]',
 			params: { one: 'one', two: 'two/three' },
 			expected: '/blog/one/two/three'
 		},
+		{
+			route: '/blog/[one=matcher]/[...two]/',
+			params: { one: 'one', two: 'two/three' },
+			expected: '/blog/one/two/three/'
+		},
 		{
 			route: '/blog/[one=matcher]/[[two]]',
 			params: { one: 'one' },
 			expected: '/blog/one'
 		},
+		{
+			route: '/blog/[one=matcher]/[[two]]/',
+			params: { one: 'one' },
+			expected: '/blog/one/'
+		},
 		{
 			route: '/blog/[one]/[two]-and-[three]',
 			params: { one: 'one', two: '2', three: '3' },
 			expected: '/blog/one/2-and-3'
 		},
+		{
+			route: '/blog/[one]/[two]-and-[three]/',
+			params: { one: 'one', two: '2', three: '3' },
+			expected: '/blog/one/2-and-3/'
+		},
 		{
 			route: '/blog/[...one]',
 			params: { one: '' },
 			expected: '/blog'
 		},
+		{
+			route: '/blog/[...one]/',
+			params: { one: '' },
+			expected: '/blog/'
+		},
 		{
 			route: '/blog/[one]/[...two]-not-three',
 			params: { one: 'one', two: 'two/2' },
 			expected: '/blog/one/two/2-not-three'
+		},
+		{
+			route: '/blog/[one]/[...two]-not-three/',
+			params: { one: 'one', two: 'two/2' },
+			expected: '/blog/one/two/2-not-three/'
 		}
 	];