Don’t count tasks that are not defined as list items correctly

app/models/concerns/taskable.rb

@@ -11,8 +11,8 @@ module Taskable
   INCOMPLETE   = 'incomplete'.freeze
   ITEM_PATTERN = /
     ^
-    \s*(?:[-+*]|(?:\d+\.))? # optional list prefix
-    \s*                     # optional whitespace prefix
+    \s*(?:[-+*]|(?:\d+\.)) # list prefix required - task item has to be always in a list
+    \s+                       # whitespace prefix has to be always presented for a list item
     (\[\s\]|\[[xX]\])         # checkbox
     (\s.+)                    # followed by whitespace and some text.
   /x

changelogs/unreleased/26068_tasklist_issue.yml

+---
+title: Don’t count tasks that are not defined as list items correctly
+merge_request: 8526
+author:

spec/support/taskable_shared_examples.rb

@@ -72,6 +72,25 @@ shared_examples 'a Taskable' do
     end
   end
 
+  describe 'with tasks that are not formatted correctly' do
+    before do
+      subject.description = <<-EOT.strip_heredoc
+        [ ] task 1
+        [ ] task 2
+
+        - [ ]task 1
+        -[ ] task 2
+      EOT
+    end
+
+    it 'returns the correct task status' do
+      expect(subject.task_status).to match('0 of')
+      expect(subject.task_status).to match('0 tasks completed')
+      expect(subject.task_status_short).to match('0/')
+      expect(subject.task_status_short).to match('0 task')
+    end
+  end
+
   describe 'with a complete task' do
     before do
       subject.description = <<-EOT.strip_heredoc