Fix #141 by explicitly close stream when Exception occurs

src/ExcelLibrary.Test/ExcelLibrary.Test.csproj

@@ -64,6 +64,7 @@
     <Compile Include="CodeLib\FastSearchListTest.cs" />
     <Compile Include="DataSetHelperTest.cs" />
     <Compile Include="Issue\Issue10_Test.cs" />
+    <Compile Include="Issue\Issue141_Test.cs" />
     <Compile Include="SimpleTest.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
   </ItemGroup>

src/ExcelLibrary.Test/Issue/Issue141_Test.cs

@@ -0,0 +1,41 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Text;
+using ExcelLibrary.CompoundDocumentFormat;
+using NUnit.Framework;
+
+namespace ExcelLibrary.Test.Issue
+{
+    [TestFixture]
+    class Issue141_Test
+    {
+        [Test]
+        public void Test()
+        {
+            string filename = Path.GetTempFileName();
+
+            try
+            {
+                // create invalid file for read
+                using (var writer = new StreamWriter(filename))
+                    writer.WriteLine("test");
+
+                try
+                {
+                    // triggers exception
+                    CompoundDocument.Open(filename);
+                }
+                catch
+                {
+                    Assert.IsTrue(true, "Expection trigger.");
+                }
+            }
+            finally
+            {
+                // should not trigger any IO Exception
+                File.Delete(filename);
+            }
+        }
+    }
+}

src/ExcelLibrary/Office/CompoundDocumentFormat/CompoundDocument.cs

@@ -58,7 +58,16 @@ public static CompoundDocument Create(string file)
         public static CompoundDocument Open(string file)
         {
             FileStream stream = File.Open(file, FileMode.Open, FileAccess.ReadWrite, FileShare.Read);
-            return Open(stream);
+
+            try
+            {
+                return Open(stream);
+            }
+            catch (Exception ex)
+            {
+                stream.Close();
+                throw ex;
+            }
         }
 
         public static CompoundDocument Create(Stream stream)