fix(trie-router): fix the rule for capturing named parameter (#419)

Close #418

deno_dist/router/trie-router/node.ts

@@ -135,9 +135,23 @@ export class Node<T> {
       const part: string = parts[i]
       const isLast = i === len - 1
       const tempNodes: Node<T>[] = []
+      let matched = false
 
       for (let j = 0, len2 = curNodes.length; j < len2; j++) {
         const node = curNodes[j]
+        const nextNode = node.children[part]
+
+        if (nextNode) {
+          if (isLast === true) {
+            // '/hello/*' => match '/hello'
+            if (nextNode.children['*']) {
+              handlerSets.push(...this.getHandlerSets(nextNode.children['*'], method, true))
+            }
+            handlerSets.push(...this.getHandlerSets(nextNode, method))
+            matched = true
+          }
+          tempNodes.push(nextNode)
+        }
 
         for (let k = 0, len3 = node.patterns.length; k < len3; k++) {
           const pattern = node.patterns[k]
@@ -165,24 +179,16 @@ export class Node<T> {
               }
               tempNodes.push(node.children[key])
             }
-            if (typeof name === 'string') {
+
+            // '/book/a'     => not-slug
+            // '/book/:slug' => slug
+            // GET /book/a   ~> no-slug, param['slug'] => undefined
+            // GET /book/foo ~> slug, param['slug'] => foo
+            if (typeof name === 'string' && !matched) {
               params[name] = part
             }
           }
         }
-
-        const nextNode = node.children[part]
-
-        if (nextNode) {
-          if (isLast === true) {
-            // '/hello/*' => match '/hello'
-            if (nextNode.children['*']) {
-              handlerSets.push(...this.getHandlerSets(nextNode.children['*'], method, true))
-            }
-            handlerSets.push(...this.getHandlerSets(nextNode, method))
-          }
-          tempNodes.push(nextNode)
-        }
       }
 
       curNodes = tempNodes

src/router/trie-router/node.test.ts

@@ -527,3 +527,21 @@ describe('star', () => {
     expect(res?.handlers).toEqual(['/*', '*', '/x', '/x/*'])
   })
 })
+
+describe('Routing order With named parameters', () => {
+  const node = new Node()
+  node.insert('get', '/book/a', 'no-slug')
+  node.insert('get', '/book/:slug', 'slug')
+  it('/book/a', () => {
+    const res = node.search('get', '/book/a')
+    expect(res).not.toBeNull()
+    expect(res?.handlers).toEqual(['no-slug', 'slug'])
+    expect(res?.params['slug']).toBeUndefined()
+  })
+  it('/book/foo', () => {
+    const res = node.search('get', '/book/foo')
+    expect(res).not.toBeNull()
+    expect(res?.handlers).toEqual(['slug'])
+    expect(res?.params['slug']).toBe('foo')
+  })
+})

src/router/trie-router/node.ts

@@ -135,9 +135,23 @@ export class Node<T> {
       const part: string = parts[i]
       const isLast = i === len - 1
       const tempNodes: Node<T>[] = []
+      let matched = false
 
       for (let j = 0, len2 = curNodes.length; j < len2; j++) {
         const node = curNodes[j]
+        const nextNode = node.children[part]
+
+        if (nextNode) {
+          if (isLast === true) {
+            // '/hello/*' => match '/hello'
+            if (nextNode.children['*']) {
+              handlerSets.push(...this.getHandlerSets(nextNode.children['*'], method, true))
+            }
+            handlerSets.push(...this.getHandlerSets(nextNode, method))
+            matched = true
+          }
+          tempNodes.push(nextNode)
+        }
 
         for (let k = 0, len3 = node.patterns.length; k < len3; k++) {
           const pattern = node.patterns[k]
@@ -165,24 +179,16 @@ export class Node<T> {
               }
               tempNodes.push(node.children[key])
             }
-            if (typeof name === 'string') {
+
+            // '/book/a'     => not-slug
+            // '/book/:slug' => slug
+            // GET /book/a   ~> no-slug, param['slug'] => undefined
+            // GET /book/foo ~> slug, param['slug'] => foo
+            if (typeof name === 'string' && !matched) {
               params[name] = part
             }
           }
         }
-
-        const nextNode = node.children[part]
-
-        if (nextNode) {
-          if (isLast === true) {
-            // '/hello/*' => match '/hello'
-            if (nextNode.children['*']) {
-              handlerSets.push(...this.getHandlerSets(nextNode.children['*'], method, true))
-            }
-            handlerSets.push(...this.getHandlerSets(nextNode, method))
-          }
-          tempNodes.push(nextNode)
-        }
       }
 
       curNodes = tempNodes

src/router/trie-router/router.test.ts

@@ -129,3 +129,19 @@ describe('page', () => {
     expect(res?.handlers).toEqual(['page', 'fallback'])
   })
 })
+
+describe('routing order with named parameters', () => {
+  const router = new TrieRouter<string>()
+  router.add('GET', '/book/a', 'no-slug')
+  router.add('GET', '/book/:slug', 'slug')
+  it('GET /book/a', async () => {
+    const res = router.match('GET', '/book/a')
+    expect(res?.handlers).toEqual(['no-slug', 'slug'])
+    expect(res?.params['slug']).toBeUndefined()
+  })
+  it('GET /book/foo', async () => {
+    const res = router.match('GET', '/book/foo')
+    expect(res?.handlers).toEqual(['slug'])
+    expect(res?.params['slug']).toBe('foo')
+  })
+})