FEATURE: improve search so it searches sub categories by default

If you want an exact category match use `category:=howto` or `#=howto"

lib/search.rb

@@ -316,15 +316,32 @@ class Search
   end
 
   advanced_filter(/category:(.+)/) do |posts,match|
-    category_ids = Category.where('name ilike ? OR id = ? OR parent_category_id = ?', match, match.to_i, match.to_i).pluck(:id)
+    exact = false
+
+    if match[0] == "="
+      exact = true
+      match = match[1..-1]
+    end
+
+    category_ids = Category.where('slug ilike ? OR name ilike ? OR id = ?',
+                                  match, match, match.to_i).pluck(:id)
     if category_ids.present?
+
+      unless exact
+        category_ids +=
+          Category.where('parent_category_id = ?', category_ids.first).pluck(:id)
+      end
+
       posts.where("topics.category_id IN (?)", category_ids)
     else
       posts.where("1 = 0")
     end
   end
 
-  advanced_filter(/^\#([a-zA-Z0-9\-:]+)/) do |posts,match|
+  advanced_filter(/^\#([a-zA-Z0-9\-:=]+)/) do |posts,match|
+
+    exact = true
+
     slug = match.to_s.split(":")
     if slug[1]
       # sub category
@@ -332,11 +349,26 @@ class Search
       category_id = Category.where(slug: slug[1].downcase, parent_category_id: parent_category_id).pluck(:id).first
     else
       # main category
-      category_id = Category.where(slug: slug[0].downcase, parent_category_id: nil).pluck(:id).first
+      if slug[0][0] == "="
+        slug[0] = slug[0][1..-1]
+      else
+        exact = false
+      end
+
+      category_id = Category.where(slug: slug[0].downcase)
+        .order('case when parent_category_id is null then 0 else 1 end')
+        .pluck(:id)
+        .first
     end
 
     if category_id
-      posts.where("topics.category_id = ?", category_id)
+      category_ids = [category_id]
+
+      unless exact
+        category_ids +=
+          Category.where('parent_category_id = ?', category_id).pluck(:id)
+      end
+      posts.where("topics.category_id IN (?)", category_ids)
     else
       posts.where("topics.id IN (
         SELECT DISTINCT(tt.topic_id)

spec/components/search_spec.rb

@@ -580,21 +580,22 @@ describe Search do
       # main category
       category = Fabricate(:category, name: 'category 24', slug: 'category-24')
       topic = Fabricate(:topic, created_at: 3.months.ago, category: category)
-      post = Fabricate(:post, raw: 'hi this is a test 123', topic: topic)
+      post = Fabricate(:post, raw: 'Sams first post', topic: topic)
 
-      expect(Search.execute('this is a test #category-24').posts.length).to eq(1)
-      expect(Search.execute("this is a test category:#{category.id}").posts.length).to eq(1)
-      expect(Search.execute('this is a test #category-25').posts.length).to eq(0)
+      expect(Search.execute('sams post #category-24').posts.length).to eq(1)
+      expect(Search.execute("sams post category:#{category.id}").posts.length).to eq(1)
+      expect(Search.execute('sams post #category-25').posts.length).to eq(0)
 
-      # sub category
       sub_category = Fabricate(:category, name: 'sub category', slug: 'sub-category', parent_category_id: category.id)
       second_topic = Fabricate(:topic, created_at: 3.months.ago, category: sub_category)
-      Fabricate(:post, raw: 'hi testing again 123', topic: second_topic)
+      Fabricate(:post, raw: 'sams second post', topic: second_topic)
 
-      expect(Search.execute('testing again #category-24:sub-category').posts.length).to eq(1)
-      expect(Search.execute("testing again category:#{category.id}").posts.length).to eq(2)
-      expect(Search.execute("testing again category:#{sub_category.id}").posts.length).to eq(1)
-      expect(Search.execute('testing again #sub-category').posts.length).to eq(0)
+      expect(Search.execute("sams post category:category-24").posts.length).to eq(2)
+      expect(Search.execute("sams post category:=category-24").posts.length).to eq(1)
+
+      expect(Search.execute("sams post #category-24").posts.length).to eq(2)
+      expect(Search.execute("sams post #=category-24").posts.length).to eq(1)
+      expect(Search.execute("sams post #sub-category").posts.length).to eq(1)
 
       # tags
       topic.tags = [Fabricate(:tag, name: 'alpha')]