From bbdfc1917306f7ebdaa5f7600d343cedec7f472a Mon Sep 17 00:00:00 2001
From: Oluwatoni Solarin-Sodara <toni.edward@outlook.com>
Date: Mon, 5 Feb 2018 10:54:17 +0100
Subject: [PATCH] restore original uninstrumented modules after coverage is run

---
 src/coverlet.core/Coverage.cs                         |  2 ++
 src/coverlet.core/Helpers/InstrumentationHelper.cs    | 11 +++++++++++
 src/coverlet.core/Instrumentation/Instrumenter.cs     | 11 ++++++++++-
 .../Instrumentation/InstrumenterResult.cs             |  2 ++
 4 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/src/coverlet.core/Coverage.cs b/src/coverlet.core/Coverage.cs
index de63cdd..e729b7e 100644
--- a/src/coverlet.core/Coverage.cs
+++ b/src/coverlet.core/Coverage.cs
@@ -53,6 +53,8 @@ namespace Coverlet.Core
                 data.Add(instrumenterResult.Module, documents);
             }
 
+            InstrumentationHelper.RestoreOriginalModules(_results);
+
             return new CoverageResult
             {
                 Identifier = _identifier,
diff --git a/src/coverlet.core/Helpers/InstrumentationHelper.cs b/src/coverlet.core/Helpers/InstrumentationHelper.cs
index 62e5f4e..2c3c8d5 100644
--- a/src/coverlet.core/Helpers/InstrumentationHelper.cs
+++ b/src/coverlet.core/Helpers/InstrumentationHelper.cs
@@ -3,6 +3,8 @@ using System.IO;
 using System.Linq;
 using System.Reflection.PortableExecutable;
 
+using Coverlet.Core.Instrumentation;
+
 namespace Coverlet.Core.Helpers
 {
     internal static class InstrumentationHelper
@@ -32,5 +34,14 @@ namespace Coverlet.Core.Helpers
                 return false;
             }
         }
+
+        public static void RestoreOriginalModules(IEnumerable<InstrumenterResult> results)
+        {
+            foreach (var result in results)
+            {
+                File.Copy(result.OriginalModuleTempPath, result.OriginalModulePath, true);
+                File.Delete(result.OriginalModuleTempPath);
+            }
+        }
     }
 }
\ No newline at end of file
diff --git a/src/coverlet.core/Instrumentation/Instrumenter.cs b/src/coverlet.core/Instrumentation/Instrumenter.cs
index 90fd06f..f2943d8 100644
--- a/src/coverlet.core/Instrumentation/Instrumenter.cs
+++ b/src/coverlet.core/Instrumentation/Instrumenter.cs
@@ -27,10 +27,19 @@ namespace Coverlet.Core.Instrumentation
                 Path.GetFileNameWithoutExtension(_module) + "_" + _identifier
             );
 
+            string originalModuleTempPath = Path.Combine(
+                Path.GetTempPath(),
+                Path.GetFileNameWithoutExtension(_module) + "_" + _identifier + ".dll"
+            );
+
+            File.Copy(_module, originalModuleTempPath);
+
             _result = new InstrumenterResult
             {
                 Module = Path.GetFileNameWithoutExtension(_module),
-                ReportPath = reportPath
+                ReportPath = reportPath,
+                OriginalModulePath = _module,
+                OriginalModuleTempPath = originalModuleTempPath
             };
 
             InstrumentModule();
diff --git a/src/coverlet.core/Instrumentation/InstrumenterResult.cs b/src/coverlet.core/Instrumentation/InstrumenterResult.cs
index f8078d0..9062fbe 100644
--- a/src/coverlet.core/Instrumentation/InstrumenterResult.cs
+++ b/src/coverlet.core/Instrumentation/InstrumenterResult.cs
@@ -21,6 +21,8 @@ namespace Coverlet.Core.Instrumentation
         public InstrumenterResult() => Documents = new List<Document>();
         public string Module;
         public string ReportPath;
+        public string OriginalModulePath;
+        public string OriginalModuleTempPath;
         public List<Document> Documents { get; private set; }
     }
 }
\ No newline at end of file