Fix duplicate terminal punctuation in summary

lib/yard/docstring.rb

@@ -192,7 +192,9 @@ def summary
         end
       end
       @summary = stripped[0..idx]
-      if [email protected]? && @summary !~ /\A\s*\{include:.+\}\s*\Z/
+      if [email protected]? &&
+         @summary !~ /\A\s*\{include:.+\}\s*\Z/ && # Summary is copied using +{include:...}+
+         @summary !~ /[!?]\s*\Z/ # Summary ends in a terminal punctuation
         @summary += '.'
       end
       @summary

spec/docstring_spec.rb

@@ -94,6 +94,14 @@
       Registry.clear
     end
 
+    it "does not attach period if summary ends with '?'" do
+      expect(Docstring.new("Is this object correctly configured?").summary).to eq "Is this object correctly configured?"
+    end
+
+    it "does not attach period if summary ends with '!'" do
+      expect(Docstring.new("Invoke this method first!").summary).to eq "Invoke this method first!"
+    end
+
     it "handles references embedded in summary" do
       expect(Docstring.new("Aliasing {Test.test}. Done.").summary).to eq "Aliasing {Test.test}."
     end

spec/templates/examples/class001.html

@@ -150,7 +150,7 @@ <h2>
 
 
 
-    <span class="summary_desc"><div class='inline'>constructor method!.</div></span>
+    <span class="summary_desc"><div class='inline'>constructor method!</div></span>
 
 </li>