Add unit test for shouldHardNavigate (#45303)

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Similar to the other PRs. This adds a test for shouldHardNavigate. It
also removes the `treePatch` variable from the function as it was only
passed around, not used.

## Bug

- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a helpful link attached, see
[`contributing.md`](https://github.com/vercel/next.js/blob/canary/contributing.md)

## Feature

- [ ] Implements an existing feature request or RFC. Make sure the
feature request has been accepted for implementation before opening a
PR.
- [ ] Related issues linked using `fixes #number`
- [ ]
[e2e](https://github.com/vercel/next.js/blob/canary/contributing/core/testing.md#writing-tests-for-nextjs)
tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see
[`contributing.md`](https://github.com/vercel/next.js/blob/canary/contributing.md)

## Documentation / Examples

- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)

Co-authored-by: kodiakhq[bot] <49736102+kodiakhq[bot]@users.noreply.github.com>

packages/next/src/client/components/router-reducer/router-reducer.ts

@@ -335,8 +335,7 @@ function clientReducer(
             shouldHardNavigate(
               // TODO-APP: remove ''
               ['', ...flightSegmentPath],
-              state.tree,
-              newTree
+              state.tree
             )
 
           if (hardNavigate) {

packages/next/src/client/components/router-reducer/should-hard-navigate.test.tsx

@@ -0,0 +1,173 @@
+import React from 'react'
+import type { FlightData, FlightRouterState } from '../../../server/app-render'
+import { shouldHardNavigate } from './should-hard-navigate'
+
+describe('shouldHardNavigate', () => {
+  it('should return false if the segments match', () => {
+    const getInitialRouterStateTree = (): FlightRouterState => [
+      '',
+      {
+        children: [
+          'linking',
+          {
+            children: ['', {}],
+          },
+        ],
+      },
+      undefined,
+      undefined,
+      true,
+    ]
+    const initialRouterStateTree = getInitialRouterStateTree()
+    const getFlightData = (): FlightData => {
+      return [
+        [
+          'children',
+          'linking',
+          'children',
+          'about',
+          [
+            'about',
+            {
+              children: ['', {}],
+            },
+          ],
+          <h1>About Page!</h1>,
+          <>
+            <title>About page!</title>
+          </>,
+        ],
+      ]
+    }
+    const flightData = getFlightData()
+
+    if (typeof flightData === 'string') {
+      throw new Error('invalid flight data')
+    }
+
+    // Mirrors the way router-reducer values are passed in.
+    const flightDataPath = flightData[0]
+    const flightSegmentPath = flightDataPath.slice(0, -3)
+
+    const result = shouldHardNavigate(
+      ['', ...flightSegmentPath],
+      initialRouterStateTree
+    )
+
+    expect(result).toBe(false)
+  })
+
+  it('should return false if segments are dynamic and match', () => {
+    const getInitialRouterStateTree = (): FlightRouterState => [
+      '',
+      {
+        children: [
+          'link-hard-push',
+          {
+            children: [
+              ['id', '123', 'd'],
+              {
+                children: ['', {}],
+              },
+            ],
+          },
+        ],
+      },
+      null,
+      null,
+      true,
+    ]
+    const initialRouterStateTree = getInitialRouterStateTree()
+    const getFlightData = (): FlightData => {
+      return [
+        [
+          'children',
+          'link-hard-push',
+          'children',
+          ['id', '123', 'd'],
+          [
+            ['id', '123', 'd'],
+            {
+              children: ['', {}],
+            },
+          ],
+          null,
+          null,
+        ],
+      ]
+    }
+    const flightData = getFlightData()
+
+    if (typeof flightData === 'string') {
+      throw new Error('invalid flight data')
+    }
+
+    // Mirrors the way router-reducer values are passed in.
+    const flightDataPath = flightData[0]
+    const flightSegmentPath = flightDataPath.slice(0, -3)
+
+    const result = shouldHardNavigate(
+      ['', ...flightSegmentPath],
+      initialRouterStateTree
+    )
+
+    expect(result).toBe(false)
+  })
+
+  it('should return true if segments are dynamic and mismatch', () => {
+    const getInitialRouterStateTree = (): FlightRouterState => [
+      '',
+      {
+        children: [
+          'link-hard-push',
+          {
+            children: [
+              ['id', '456', 'd'],
+              {
+                children: ['', {}],
+              },
+            ],
+          },
+        ],
+      },
+      null,
+      null,
+      true,
+    ]
+    const initialRouterStateTree = getInitialRouterStateTree()
+    const getFlightData = (): FlightData => {
+      return [
+        [
+          'children',
+          'link-hard-push',
+          'children',
+          ['id', '123', 'd'],
+          [
+            ['id', '123', 'd'],
+            {
+              children: ['', {}],
+            },
+          ],
+          null,
+          null,
+        ],
+      ]
+    }
+    const flightData = getFlightData()
+
+    if (typeof flightData === 'string') {
+      throw new Error('invalid flight data')
+    }
+
+    // Mirrors the way router-reducer values are passed in.
+    const flightDataPath = flightData[0]
+    const flightSegmentPath = flightDataPath.slice(0, -3)
+
+    const result = shouldHardNavigate(
+      ['', ...flightSegmentPath],
+      initialRouterStateTree
+    )
+
+    expect(result).toBe(true)
+  })
+})

packages/next/src/client/components/router-reducer/should-hard-navigate.ts

@@ -5,10 +5,10 @@ import {
 } from '../../../server/app-render'
 import { matchSegment } from '../match-segments'
 
+// TODO-APP: flightSegmentPath will be empty in case of static response, needs to be handled.
 export function shouldHardNavigate(
   flightSegmentPath: FlightDataPath,
-  flightRouterState: FlightRouterState,
-  treePatch: FlightRouterState
+  flightRouterState: FlightRouterState
 ): boolean {
   const [segment, parallelRoutes] = flightRouterState
   // TODO-APP: Check if `as` can be replaced.
@@ -35,7 +35,6 @@ export function shouldHardNavigate(
 
   return shouldHardNavigate(
     flightSegmentPath.slice(2),
-    parallelRoutes[parallelRouteKey],
-    treePatch
+    parallelRoutes[parallelRouteKey]
   )
 }