fix(resolve): use current location if not provided (#2390)

Fixes #2385

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src/index.js

@@ -186,9 +186,10 @@ export default class VueRouter {
     normalizedTo: Location,
     resolved: Route
   } {
+    current = current || this.history.current
     const location = normalizeLocation(
       to,
-      current || this.history.current,
+      current,
       append,
       this
     )

test/unit/specs/api.spec.js

@@ -44,6 +44,46 @@ describe('router.onReady', () => {
   })
 })
 
+describe('route matching', () => {
+  it('resolves parent params when using current route', () => {
+    const router = new Router({
+      mode: 'abstract',
+      routes: [
+        {
+          path: '/a/:id',
+          component: { name: 'A' },
+          children: [{ name: 'b', path: 'b', component: { name: 'B' }}]
+        }
+      ]
+    })
+
+    router.push('/a/1')
+
+    const { route, resolved } = router.resolve({ name: 'b' })
+    expect(route.params).toEqual({ id: '1' })
+    expect(resolved.params).toEqual({ id: '1' })
+  })
+
+  it('can override currentRoute', () => {
+    const router = new Router({
+      mode: 'abstract',
+      routes: [
+        {
+          path: '/a/:id',
+          component: { name: 'A' },
+          children: [{ name: 'b', path: 'b', component: { name: 'B' }}]
+        }
+      ]
+    })
+
+    router.push('/a/1')
+
+    const { route, resolved } = router.resolve({ name: 'b' }, { params: { id: '2' }, path: '/a/2' })
+    expect(route.params).toEqual({ id: '2' })
+    expect(resolved.params).toEqual({ id: '2' })
+  })
+})
+
 describe('router.addRoutes', () => {
   it('should work', () => {
     const router = new Router({