Prevent infinite loop on file collision when stdin closed

Author: tpope

lib/thor/shell/basic.rb

@@ -252,6 +252,9 @@ def file_collision(destination)
           )
 
           case answer
+          when nil
+            say ""
+            return true
           when is?(:yes), is?(:force), ""
             return true
           when is?(:no), is?(:skip)

spec/shell/basic_spec.rb

@@ -310,6 +310,12 @@ def  #456  Lanç...
       shell.file_collision("foo")
     end
 
+    it "outputs a new line and returns true if stdin is closed" do
+      expect($stdout).to receive(:print).with("\n")
+      expect(Thor::LineEditor).to receive(:readline).and_return(nil)
+      expect(shell.file_collision("foo")).to be true
+    end
+
     it "returns true if the user chooses default option" do
       expect(Thor::LineEditor).to receive(:readline).and_return("")
       expect(shell.file_collision("foo")).to be true