Fix filtering taxonomy terms by collection

src/Stache/Indexes/Terms/Associations.php

@@ -23,6 +23,7 @@ public function getItems()
                                     'value' => $value,
                                     'slug' => Str::slug($value),
                                     'entry' => $entry->id(),
+                                    'collection' => $entry->collectionHandle(),
                                     'site' => $entry->locale(),
                                 ];
                             });

src/Stache/Query/TermQueryBuilder.php

@@ -56,6 +56,10 @@ protected function getFilteredKeys()
             ? Facades\Taxonomy::handles()
             : $this->taxonomies;
 
+        if ($this->collections) {
+            $this->filterUsagesWithinCollections($taxonomies);
+        }
+
         $keys = empty($this->wheres)
             ? $this->getKeysFromTaxonomies($taxonomies)
             : $this->getKeysFromTaxonomiesWithWheres($taxonomies, $this->wheres);
@@ -143,4 +147,16 @@ public function get($columns = ['*'])
 
         return $items;
     }
+
+    private function filterUsagesWithinCollections($taxonomies)
+    {
+        $this->whereIn('id', collect($taxonomies)->flatMap(function ($taxonomy) {
+            return $this->store->store($taxonomy)
+                ->index('associations')
+                ->items()->whereIn('collection', $this->collections)
+                ->map(function ($item) use ($taxonomy) {
+                    return $taxonomy.'::'.$item['slug'];
+                });
+        })->all());
+    }
 }

src/Stache/Stores/TaxonomyTermsStore.php

@@ -111,6 +111,7 @@ public function sync($entry, $terms)
                 'value' => $value,
                 'slug' => $slug,
                 'entry' => $entry->id(),
+                'collection' => $entry->collectionHandle(),
                 'site' => $entry->locale(),
             ]);
         }

tests/Data/Taxonomies/TermQueryBuilderTest.php

@@ -0,0 +1,137 @@
+<?php
+
+namespace Tests\Data\Taxonomies;
+
+use Facades\Tests\Factories\EntryFactory;
+use Statamic\Facades\Collection;
+use Statamic\Facades\Taxonomy;
+use Statamic\Facades\Term;
+use Statamic\Taxonomies\LocalizedTerm;
+use Statamic\Taxonomies\TermCollection;
+use Tests\PreventSavingStacheItemsToDisk;
+use Tests\TestCase;
+
+class TermQueryBuilderTest extends TestCase
+{
+    use PreventSavingStacheItemsToDisk;
+
+    /** @test */
+    public function it_gets_terms()
+    {
+        Taxonomy::make('tags')->save();
+        Term::make('a')->taxonomy('tags')->data([])->save();
+        Term::make('b')->taxonomy('tags')->data([])->save();
+        Term::make('c')->taxonomy('tags')->data([])->save();
+
+        $terms = Term::query()->get();
+        $this->assertInstanceOf(TermCollection::class, $terms);
+        $this->assertEveryItemIsInstanceOf(LocalizedTerm::class, $terms);
+    }
+
+    /** @test */
+    public function it_filters_using_wheres()
+    {
+        Taxonomy::make('tags')->save();
+        Term::make('a')->taxonomy('tags')->data(['test' => 'foo'])->save();
+        Term::make('b')->taxonomy('tags')->data(['test' => 'bar'])->save();
+        Term::make('c')->taxonomy('tags')->data(['test' => 'foo'])->save();
+
+        $terms = Term::query()->where('test', 'foo')->get();
+        $this->assertEquals(['a', 'c'], $terms->map->slug()->sort()->values()->all());
+    }
+
+    /** @test */
+    public function it_filters_by_taxonomy()
+    {
+        Taxonomy::make('tags')->save();
+        Taxonomy::make('categories')->save();
+        Taxonomy::make('colors')->save();
+        Term::make('a')->taxonomy('tags')->data([])->save();
+        Term::make('b')->taxonomy('categories')->data([])->save();
+        Term::make('c')->taxonomy('colors')->data([])->save();
+        Term::make('d')->taxonomy('tags')->data([])->save();
+
+        $terms = Term::query()->where('taxonomy', 'tags')->get();
+        $this->assertEquals(['a', 'd'], $terms->map->slug()->sort()->values()->all());
+
+        $terms = Term::query()->whereIn('taxonomy', ['tags', 'categories'])->get();
+        $this->assertEquals(['a', 'b', 'd'], $terms->map->slug()->sort()->values()->all());
+    }
+
+    /** @test */
+    public function it_sorts()
+    {
+        Taxonomy::make('tags')->save();
+        Term::make('a')->taxonomy('tags')->data(['test' => 4])->save();
+        Term::make('b')->taxonomy('tags')->data(['test' => 2])->save();
+        Term::make('c')->taxonomy('tags')->data(['test' => 1])->save();
+        Term::make('d')->taxonomy('tags')->data(['test' => 5])->save();
+        Term::make('e')->taxonomy('tags')->data(['test' => 3])->save();
+
+        $terms = Term::query()->orderBy('test')->get();
+        $this->assertEquals(['c', 'b', 'e', 'a', 'd'], $terms->map->slug()->all());
+    }
+
+    /** @test */
+    public function it_filters_usage_in_collections()
+    {
+        Taxonomy::make('tags')->save();
+        Taxonomy::make('cats')->save();
+
+        Collection::make('blog')->taxonomies(['tags', 'cats'])->save();
+        Collection::make('news')->taxonomies(['tags', 'cats'])->save();
+
+        EntryFactory::collection('blog')->data(['tags' => ['a'], 'cats' => ['f']])->create();
+        EntryFactory::collection('blog')->data(['tags' => ['c'], 'cats' => ['g']])->create();
+        EntryFactory::collection('news')->data(['tags' => ['a'], 'cats' => ['f']])->create();
+        EntryFactory::collection('news')->data(['tags' => ['b'], 'cats' => ['h']])->create();
+
+        Term::make('a')->taxonomy('tags')->data([])->save();
+        Term::make('b')->taxonomy('tags')->data([])->save();
+        Term::make('c')->taxonomy('tags')->data([])->save();
+        Term::make('d')->taxonomy('tags')->data([])->save();
+        Term::make('e')->taxonomy('cats')->data([])->save();
+        Term::make('f')->taxonomy('cats')->data([])->save();
+        Term::make('g')->taxonomy('cats')->data([])->save();
+        Term::make('h')->taxonomy('cats')->data([])->save();
+
+        $this->assertEquals(['cats::f', 'cats::g', 'tags::a', 'tags::c'],
+            Term::query()
+                ->where('collection', 'blog')
+                ->get()->map->id()->sort()->values()->all()
+        );
+
+        $this->assertEquals(['tags::a', 'tags::c'],
+            Term::query()
+                ->where('collection', 'blog')
+                ->where('taxonomy', 'tags')
+                ->get()->map->id()->sort()->values()->all()
+        );
+
+        $this->assertEquals(['cats::f', 'cats::h', 'tags::a', 'tags::b'],
+            Term::query()
+                ->where('collection', 'news')
+                ->get()->map->id()->sort()->values()->all()
+        );
+
+        $this->assertEquals(['tags::a', 'tags::b'],
+            Term::query()
+                ->where('collection', 'news')
+                ->where('taxonomy', 'tags')
+                ->get()->map->id()->sort()->values()->all()
+        );
+
+        $this->assertEquals(['cats::f', 'cats::g', 'cats::h', 'tags::a', 'tags::b', 'tags::c'],
+            Term::query()
+                ->whereIn('collection', ['blog', 'news'])
+                ->get()->map->id()->sort()->values()->all()
+        );
+
+        $this->assertEquals(['tags::a', 'tags::b', 'tags::c'],
+            Term::query()
+                ->whereIn('collection', ['blog', 'news'])
+                ->where('taxonomy', 'tags')
+                ->get()->map->id()->sort()->values()->all()
+        );
+    }
+}