From 64ffb413b3e5309d8e92bff8f0e3b2dfde374274 Mon Sep 17 00:00:00 2001
From: edalzell <erin@silentz.co>
Date: Fri, 13 Nov 2026 21:32:22 -0700
Subject: [PATCH 1/8] Test sibling URIs are built once when validating a tree

---
 .../Collections/UpdateCollectionTreeTest.php  | 67 +++++++++++++++++++
 1 file changed, 67 insertions(+)

diff --git a/tests/Feature/Collections/UpdateCollectionTreeTest.php b/tests/Feature/Collections/UpdateCollectionTreeTest.php
index 60d4417e386..38cda0b3d8a 100644
--- a/tests/Feature/Collections/UpdateCollectionTreeTest.php
+++ b/tests/Feature/Collections/UpdateCollectionTreeTest.php
@@ -5,9 +5,12 @@
 use Facades\Tests\Factories\EntryFactory;
 use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\Attributes\Test;
+use Statamic\Contracts\Routing\UrlBuilder as UrlBuilderContract;
 use Statamic\Facades\Collection;
 use Statamic\Facades\Entry;
 use Statamic\Facades\User;
+use Statamic\Routing\UrlBuilder;
+use Statamic\Structures\Page;
 use Tests\FakesRoles;
 use Tests\PreventSavingStacheItemsToDisk;
 use Tests\TestCase;
@@ -126,6 +129,70 @@ private function duplicateUriTest($expectsRoot)
         ], $collection->structure()->in('en')->tree());
     }
 
+    #[Test]
+    public function it_builds_each_siblings_uri_once_when_validating_moved_pages()
+    {
+        $user = tap(User::make()->makeSuper())->save();
+        $collection = tap(Collection::make('test')->routes('{parent_uri}/{slug}'))->save();
+        EntryFactory::id('e1')->collection($collection)->slug('alfa')->create();
+        EntryFactory::id('e2')->collection($collection)->slug('bravo')->create();
+        EntryFactory::id('e3')->collection($collection)->slug('charlie')->create();
+        EntryFactory::id('e4')->collection($collection)->slug('delta')->create();
+        EntryFactory::id('e5')->collection($collection)->slug('echo')->create();
+        EntryFactory::id('e6')->collection($collection)->slug('foxtrot')->create();
+        $collection->structureContents(['root' => false])->save();
+        $collection->structure()->in('en')->tree([
+            ['entry' => 'e1', 'children' => [
+                ['entry' => 'e2', 'children' => [
+                    ['entry' => 'e3'],
+                    ['entry' => 'e4'],
+                    ['entry' => 'e5'],
+                    ['entry' => 'e6'],
+                ]],
+            ]],
+        ])->save();
+
+        // Saving leaves the tree's pages cached in memory, where a request would load it fresh.
+        $collection->structure()->in('en')->flushCache();
+
+        $built = collect();
+
+        $this->app->bind(UrlBuilderContract::class, fn () => new class($built) extends UrlBuilder
+        {
+            public function __construct(private $built)
+            {
+            }
+
+            public function build($route)
+            {
+                if ($this->content instanceof Page) {
+                    $this->built->push($this->content->reference());
+                }
+
+                return parent::build($route);
+            }
+        });
+
+        $this
+            ->actingAs($user)
+            ->update($collection, ['pages' => [
+                ['id' => 'e1', 'children' => [
+                    ['id' => 'e2', 'children' => [
+                        ['id' => 'e6', 'children' => []],
+                        ['id' => 'e3', 'children' => []],
+                        ['id' => 'e4', 'children' => []],
+                        ['id' => 'e5', 'children' => []],
+                    ]],
+                ]],
+            ]])
+            ->assertOk();
+
+        $this->assertEquals(
+            ['e3' => 1, 'e4' => 1, 'e5' => 1, 'e6' => 1],
+            $built->countBy()->only(['e3', 'e4', 'e5', 'e6'])->sortKeys()->all(),
+        );
+    }
+
     #[Test]
     public function it_deletes_entries_scheduled_for_deletion()
     {

From 63a3ca953fbf92d2969ab3d3e7ca8f6147ee27f0 Mon Sep 17 00:00:00 2001
From: edalzell <erin@silentz.co>
Date: Fri, 13 Nov 2026 21:32:23 -0700
Subject: [PATCH 2/8] Build sibling URIs once per parent when validating a tree

---
 .../CP/Collections/CollectionTreeController.php | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/src/Http/Controllers/CP/Collections/CollectionTreeController.php b/src/Http/Controllers/CP/Collections/CollectionTreeController.php
index 8bec1e94bc8..987e054efca 100644
--- a/src/Http/Controllers/CP/Collections/CollectionTreeController.php
+++ b/src/Http/Controllers/CP/Collections/CollectionTreeController.php
@@ -76,21 +76,20 @@ private function validateUniqueUris($tree)
             return;
         }
 
+        $siblingUris = [];
+
         foreach ($tree->diff()->moved() as $id) {
             $page = $tree->find($id);
             $parent = $page->parent();
+            $isTopLevel = ! $parent || $parent->isRoot();
+            $key = $isTopLevel ? '' : $parent->id();
 
-            $siblings = (! $parent || $parent->isRoot())
-                ? $tree->pages()->all()->slice(1)
-                : $page->parent()->pages()->all();
-
-            $siblings = $siblings->reject(function ($sibling) use ($id) {
-                return $sibling->reference() === $id;
-            });
+            $siblingUris[$key] ??= ($isTopLevel ? $tree->pages()->all()->slice(1) : $parent->pages()->all())
+                ->mapWithKeys(fn ($sibling) => [$sibling->reference() => $sibling->uri()]);
 
-            $uris = $siblings->map->uri();
+            $uri = $siblingUris[$key][$id] ?? $page->uri();
 
-            if ($uris->contains($uri = $page->uri())) {
+            if ($siblingUris[$key]->except($id)->contains($uri)) {
                 throw ValidationException::withMessages(['uri' => trans('statamic::validation.duplicate_uri', ['value' => $uri])]);
             }
         }

From a1e2abec20a645d68d10ece2e1193d2315e32202 Mon Sep 17 00:00:00 2001
From: edalzell <erin@silentz.co>
Date: Fri, 13 Nov 2026 21:42:33 -0700
Subject: [PATCH 3/8] Test ancestor URIs are built once when validating a tree

---
 tests/Feature/Collections/UpdateCollectionTreeTest.php | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tests/Feature/Collections/UpdateCollectionTreeTest.php b/tests/Feature/Collections/UpdateCollectionTreeTest.php
index 38cda0b3d8a..7bf530c1b9a 100644
--- a/tests/Feature/Collections/UpdateCollectionTreeTest.php
+++ b/tests/Feature/Collections/UpdateCollectionTreeTest.php
@@ -188,8 +188,8 @@ public function build($route)
             ->assertOk();
 
         $this->assertEquals(
-            ['e3' => 1, 'e4' => 1, 'e5' => 1, 'e6' => 1],
-            $built->countBy()->only(['e3', 'e4', 'e5', 'e6'])->sortKeys()->all(),
+            ['e1' => 1, 'e2' => 1, 'e3' => 1, 'e4' => 1, 'e5' => 1, 'e6' => 1],
+            $built->countBy()->sortKeys()->all(),
         );
     }
 

From 1b963d24f01082af0087abd6f62d8aba4b28b816 Mon Sep 17 00:00:00 2001
From: edalzell <erin@silentz.co>
Date: Fri, 13 Nov 2026 21:42:33 -0700
Subject: [PATCH 4/8] Remember a page's URI while the URI cache is off

---
 src/Structures/Page.php | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/Structures/Page.php b/src/Structures/Page.php
index d434f84caa4..4a79230b89f 100644
--- a/src/Structures/Page.php
+++ b/src/Structures/Page.php
@@ -49,6 +49,7 @@ class Page implements Arrayable, ArrayAccess, Augmentable, BulkAugmentable, Cont
     private $routeData;
     private $status;
     private $structure;
+    private $uri;
 
     public function __construct()
     {
@@ -170,6 +171,7 @@ public function setEntry($reference): self
 
         $this->reference = $reference;
         $this->routeData = null;
+        $this->uri = null;
 
         return $this;
     }
@@ -247,14 +249,18 @@ public function uri()
             return $cached;
         }
 
+        if (! $this->tree->uriCacheEnabled() && ! is_null($this->uri)) {
+            return $this->uri;
+        }
+
         if (! $this->structure() instanceof CollectionStructure) {
-            return $uris[$this->reference] = $this->entry()->uri();
+            return $this->uri = $uris[$this->reference] = $this->entry()->uri();
         }
 
         $parentUri = $this->parent && ! $this->parent->isRoot() ? $this->parent->uri() : '';
         $parentUri = Str::replace(['.html', '.htm'], '', $parentUri);
 
-        return $uris[$this->reference] = app(UrlBuilder::class)
+        return $this->uri = $uris[$this->reference] = app(UrlBuilder::class)
             ->content($this)
             ->merge([
                 'parent_uri' => $parentUri,

From d731ef528b1af0d67c819a74a103c7d0bd46a9f0 Mon Sep 17 00:00:00 2001
From: edalzell <erin@silentz.co>
Date: Fri, 13 Nov 2026 21:58:58 -0700
Subject: [PATCH 5/8] Explain the URI reuse in tree validation

---
 .../Controllers/CP/Collections/CollectionTreeController.php     | 2 ++
 src/Structures/Page.php                                         | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/src/Http/Controllers/CP/Collections/CollectionTreeController.php b/src/Http/Controllers/CP/Collections/CollectionTreeController.php
index 987e054efca..7e53c6ddcbf 100644
--- a/src/Http/Controllers/CP/Collections/CollectionTreeController.php
+++ b/src/Http/Controllers/CP/Collections/CollectionTreeController.php
@@ -84,9 +84,11 @@ private function validateUniqueUris($tree)
             $isTopLevel = ! $parent || $parent->isRoot();
             $key = $isTopLevel ? '' : $parent->id();
 
+            // Moved pages under the same parent share siblings, so build that list once.
             $siblingUris[$key] ??= ($isTopLevel ? $tree->pages()->all()->slice(1) : $parent->pages()->all())
                 ->mapWithKeys(fn ($sibling) => [$sibling->reference() => $sibling->uri()]);
 
+            // The root is sliced off the top-level siblings, so it won't be in the list.
             $uri = $siblingUris[$key][$id] ?? $page->uri();
 
             if ($siblingUris[$key]->except($id)->contains($uri)) {
diff --git a/src/Structures/Page.php b/src/Structures/Page.php
index 4a79230b89f..b92548e24fa 100644
--- a/src/Structures/Page.php
+++ b/src/Structures/Page.php
@@ -249,6 +249,8 @@ public function uri()
             return $cached;
         }
 
+        // With the shared cache off, a page still keeps its own URI,
+        // so siblings don't each rebuild their parent's.
         if (! $this->tree->uriCacheEnabled() && ! is_null($this->uri)) {
             return $this->uri;
         }

From be815d023f5fa2d6b20e620bbd5cb273aa85db01 Mon Sep 17 00:00:00 2001
From: edalzell <erin@silentz.co>
Date: Fri, 13 Nov 2026 22:13:22 -0700
Subject: [PATCH 6/8] Test a page's URI follows its route and parent

---
 tests/Data/Structures/PageTest.php | 45 ++++++++++++++++++++++++++++++
 1 file changed, 45 insertions(+)

diff --git a/tests/Data/Structures/PageTest.php b/tests/Data/Structures/PageTest.php
index 63cd7d1b2ca..42811ab0031 100644
--- a/tests/Data/Structures/PageTest.php
+++ b/tests/Data/Structures/PageTest.php
@@ -188,6 +188,51 @@ public function slug($slug = null)
         $this->assertFalse($page->hasCustomUrl());
     }
 
+    #[Test]
+    public function it_rebuilds_the_uri_when_its_route_or_parent_changes_while_the_uri_cache_is_disabled()
+    {
+        $entry = new class extends Entry
+        {
+            public function id($id = null)
+            {
+                return 'a';
+            }
+
+            public function slug($slug = null)
+            {
+                return 'entry-slug';
+            }
+        };
+        $collection = tap(\Statamic\Facades\Collection::make('test'))->save();
+        $entry->collection('test');
+
+        $parent = Mockery::mock(Page::class);
+        $parent->shouldReceive('uri')->andReturn('/first/parent');
+        $parent->shouldReceive('isRoot')->andReturnFalse();
+
+        $otherParent = Mockery::mock(Page::class);
+        $otherParent->shouldReceive('uri')->andReturn('/second/parent');
+        $otherParent->shouldReceive('isRoot')->andReturnFalse();
+
+        $tree = $this->newTree()->disableUriCache()->setStructure(
+            $this->mock(CollectionStructure::class)->shouldReceive('collection')->andReturn($collection)->getMock()
+        );
+
+        $page = (new Page)
+            ->setTree($tree)
+            ->setRoute('{parent_uri}/{slug}')
+            ->setParent($parent)
+            ->setEntry($entry);
+
+        $this->assertEquals('/first/parent/entry-slug', $page->uri());
+
+        $page->setRoute('/foo/{parent_uri}/{slug}');
+        $this->assertEquals('/foo/first/parent/entry-slug', $page->uri());
+
+        $page->setParent($otherParent);
+        $this->assertEquals('/foo/second/parent/entry-slug', $page->uri());
+    }
+
     #[Test]
     #[DataProvider('stripExtensionFromParentUriProvider')]
     public function it_builds_a_uri_and_strips_out_file_extensions_from_parent_uri($ext)

From 26a26b683ccb7d1ecabde2b9add62a93950c9b6c Mon Sep 17 00:00:00 2001
From: edalzell <erin@silentz.co>
Date: Fri, 13 Nov 2026 22:13:39 -0700
Subject: [PATCH 7/8] Forget a page's URI when its position changes

---
 src/Structures/Page.php | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/Structures/Page.php b/src/Structures/Page.php
index b92548e24fa..8d21c5f4e82 100644
--- a/src/Structures/Page.php
+++ b/src/Structures/Page.php
@@ -121,6 +121,7 @@ public function isRedirect()
     public function setDepth($depth)
     {
         $this->depth = $depth;
+        $this->uri = null;
 
         return $this;
     }
@@ -207,6 +208,7 @@ public function parent(): ?self
     public function setParent(?self $parent): self
     {
         $this->parent = $parent;
+        $this->uri = null;
 
         return $this;
     }
@@ -214,6 +216,7 @@ public function setParent(?self $parent): self
     public function setRoute(?string $route): self
     {
         $this->route = $route;
+        $this->uri = null;
 
         return $this;
     }
@@ -307,6 +310,7 @@ public function isRoot()
     public function setTree($tree)
     {
         $this->tree = $tree;
+        $this->uri = null;
 
         return $this;
     }
@@ -314,6 +318,7 @@ public function setTree($tree)
     public function setRoot(bool $isRoot)
     {
         $this->isRoot = $isRoot;
+        $this->uri = null;
 
         return $this;
     }

From 0ed3c379cbe2f53b2c4575fa9684254a346d9f40 Mon Sep 17 00:00:00 2001
From: edalzell <erin@silentz.co>
Date: Fri, 13 Nov 2026 22:18:30 -0700
Subject: [PATCH 8/8] Trim the URI tests

---
 tests/Data/Structures/PageTest.php            |  9 +------
 .../Collections/UpdateCollectionTreeTest.php  | 24 ++++---------------
 2 files changed, 6 insertions(+), 27 deletions(-)

diff --git a/tests/Data/Structures/PageTest.php b/tests/Data/Structures/PageTest.php
index 42811ab0031..41df8b301f2 100644
--- a/tests/Data/Structures/PageTest.php
+++ b/tests/Data/Structures/PageTest.php
@@ -189,7 +189,7 @@ public function slug($slug = null)
     }
 
     #[Test]
-    public function it_rebuilds_the_uri_when_its_route_or_parent_changes_while_the_uri_cache_is_disabled()
+    public function it_rebuilds_the_uri_when_its_route_changes_while_the_uri_cache_is_disabled()
     {
         $entry = new class extends Entry
         {
@@ -210,10 +210,6 @@ public function slug($slug = null)
         $parent->shouldReceive('uri')->andReturn('/first/parent');
         $parent->shouldReceive('isRoot')->andReturnFalse();
 
-        $otherParent = Mockery::mock(Page::class);
-        $otherParent->shouldReceive('uri')->andReturn('/second/parent');
-        $otherParent->shouldReceive('isRoot')->andReturnFalse();
-
         $tree = $this->newTree()->disableUriCache()->setStructure(
             $this->mock(CollectionStructure::class)->shouldReceive('collection')->andReturn($collection)->getMock()
         );
@@ -228,9 +224,6 @@ public function slug($slug = null)
 
         $page->setRoute('/foo/{parent_uri}/{slug}');
         $this->assertEquals('/foo/first/parent/entry-slug', $page->uri());
-
-        $page->setParent($otherParent);
-        $this->assertEquals('/foo/second/parent/entry-slug', $page->uri());
     }
 
     #[Test]
diff --git a/tests/Feature/Collections/UpdateCollectionTreeTest.php b/tests/Feature/Collections/UpdateCollectionTreeTest.php
index 7bf530c1b9a..79c96de8c5f 100644
--- a/tests/Feature/Collections/UpdateCollectionTreeTest.php
+++ b/tests/Feature/Collections/UpdateCollectionTreeTest.php
@@ -137,18 +137,11 @@ public function it_builds_each_siblings_uri_once_when_validating_moved_pages()
         EntryFactory::id('e1')->collection($collection)->slug('alfa')->create();
         EntryFactory::id('e2')->collection($collection)->slug('bravo')->create();
         EntryFactory::id('e3')->collection($collection)->slug('charlie')->create();
-        EntryFactory::id('e4')->collection($collection)->slug('delta')->create();
-        EntryFactory::id('e5')->collection($collection)->slug('echo')->create();
-        EntryFactory::id('e6')->collection($collection)->slug('foxtrot')->create();
         $collection->structureContents(['root' => false])->save();
         $collection->structure()->in('en')->tree([
             ['entry' => 'e1', 'children' => [
-                ['entry' => 'e2', 'children' => [
-                    ['entry' => 'e3'],
-                    ['entry' => 'e4'],
-                    ['entry' => 'e5'],
-                    ['entry' => 'e6'],
-                ]],
+                ['entry' => 'e2'],
+                ['entry' => 'e3'],
             ]],
         ])->save();
 
@@ -177,20 +170,13 @@ public function build($route)
             ->actingAs($user)
             ->update($collection, ['pages' => [
                 ['id' => 'e1', 'children' => [
-                    ['id' => 'e2', 'children' => [
-                        ['id' => 'e6', 'children' => []],
-                        ['id' => 'e3', 'children' => []],
-                        ['id' => 'e4', 'children' => []],
-                        ['id' => 'e5', 'children' => []],
-                    ]],
+                    ['id' => 'e3', 'children' => []],
+                    ['id' => 'e2', 'children' => []],
                 ]],
             ]])
             ->assertOk();
 
-        $this->assertEquals(
-            ['e1' => 1, 'e2' => 1, 'e3' => 1, 'e4' => 1, 'e5' => 1, 'e6' => 1],
-            $built->countBy()->sortKeys()->all(),
-        );
+        $this->assertEquals(['e1' => 1, 'e2' => 1, 'e3' => 1], $built->countBy()->sortKeys()->all());
     }
 
     #[Test]