title: Git error "fatal: bad revision" when using git diff
body: <p>I am trying to show changes between the origin of a certain folder and I would like it to show only the names of those that were added and modified using the following command but it is returning an error.</p>
  
  <p>Command:</p>
  
  <pre><code>git diff --name-only --relative --diff-filter AM origin -- foldername/
  </code></pre>
  
  <p>Error:</p>
  
  <pre><code>fatal: bad revision 'origin'
  </code></pre>
  
  <p>Why did that suddenly happen? How can I resolve it?</p>
  
  <p>Edit</p>
  
  <p>using a different repo and 'origin/master' only returns different results</p>
  
  <pre><code>C:\gitprojects\samplefolder (master -&gt; origin)
  λ git diff --name-only --relative --diff-filter AM origin/master
  readme.md
  
  C:\gitprojects\samplefolder (master -&gt; origin)
  λ git diff --name-only --relative --diff-filter AM master origin/master
  readme.md
  
  C:\gitprojects\samplefolder (master -&gt; origin)
  λ git diff --name-only --relative --diff-filter AM origin
  Properties/sample.properties
  readme.md
  </code></pre>