Add more tests.

src/Compilers/CSharp/Test/Emit/Emit/ResourceTests.cs

@@ -13,6 +13,7 @@
 using Microsoft.CodeAnalysis.Test.Utilities;
 using Roslyn.Test.Utilities;
 using Xunit;
+using System.Globalization;
 
 namespace Microsoft.CodeAnalysis.CSharp.UnitTests.Emit
 {
@@ -878,5 +879,37 @@ public static void Main()
 
             Assert.Equal(expected, versionData);
         }
+
+        [Fact]
+        public void ResourceProviderStreamGivesBadLength()
+        {
+            var backingStream = new MemoryStream(new byte[] { 1, 2, 3, 4 });
+            var stream = new TestStream(
+                readFunc: backingStream.Read,
+                length: 6, // Lie about the length (> backingStream.Length)
+                getPosition: () => backingStream.Position);
+
+            var c1 = CreateCompilationWithMscorlib("");
+
+            var tmpCulture = CultureInfo.CurrentUICulture;
+            try
+            {
+                Thread.CurrentThread.CurrentUICulture = CultureInfo.InvariantCulture;
+
+                var result = c1.Emit(new MemoryStream(), manifestResources:
+                    new[]
+                    {
+                    new ResourceDescription("res", () => stream, false)
+                    });
+
+                result.Diagnostics.Verify(
+    // error CS1566: Error reading resource 'res' -- 'Resource stream ended at 4 bytes, expected 6 bytes.'
+    Diagnostic(ErrorCode.ERR_CantReadResource).WithArguments("res", "Resource stream ended at 4 bytes, expected 6 bytes.").WithLocation(1, 1));
+            }
+            finally
+            {
+                Thread.CurrentThread.CurrentUICulture = tmpCulture;
+            }
+        }
     }
 }

src/Compilers/Core/CodeAnalysisTest/InternalUtilities/StreamExtensionsTests.cs

@@ -105,5 +105,18 @@ public void ExceptionMayChangePosition()
             Assert.Throws<IOException>(() => stream.TryReadAll(destArray, 0, sourceArray.Length));
             Assert.Equal(2, backingStream.Position);
         }
+
+        [Fact]
+        public void PrematureEndOfStream()
+        {
+            var sourceArray = new byte[] { 1, 2, 3, 4 };
+            var stream = new MemoryStream(sourceArray);
+
+            var destArray = new byte[6];
+            // Try to read more bytes than exist in the stream
+            Assert.Equal(4, stream.TryReadAll(destArray, 0, 6));
+            var expected = new byte[] { 1, 2, 3, 4, 0, 0 };
+            Assert.Equal(expected, destArray);
+        }
     }
 }

src/Compilers/Core/CodeAnalysisTest/PEWriter/BlobTests.cs

@@ -877,7 +877,24 @@ public void ProperStreamRead()
             });
 
             var builder = PooledBlobBuilder.GetInstance(sourceArray.Length);
-            builder.TryWriteBytes(stream, sourceArray.Length);
+            Assert.Equal(sourceArray.Length, builder.TryWriteBytes(stream, sourceArray.Length));
+            Assert.Equal(sourceArray, builder.ToArray());
+
+            builder.Free();
+        }
+
+        [Fact]
+        public void PrematureEndOfStream()
+        {
+            var sourceArray = new byte[] { 1, 2, 3, 4 };
+            var stream = new MemoryStream(sourceArray);
+
+            var destArray = new byte[6];
+            var builder = PooledBlobBuilder.GetInstance(destArray.Length);
+
+            // Try to write more bytes than exist in the stream
+            Assert.Equal(4, builder.TryWriteBytes(stream, 6));
+
             Assert.Equal(sourceArray, builder.ToArray());
 
             builder.Free();

src/Compilers/Core/Portable/PEWriter/ManagedResource.cs

@@ -6,6 +6,7 @@
 using System.IO;
 using Microsoft.CodeAnalysis;
 using Roslyn.Utilities;
+using System.Globalization;
 
 namespace Microsoft.Cci
 {
@@ -52,7 +53,7 @@ public void WriteData(BlobBuilder resourceWriter)
                         if (bytesWritten != count)
                         {
                             throw new EndOfStreamException(
-                                    string.Format(CodeAnalysisResources.ResourceStreamEndedUnexpectedly, bytesWritten, count));
+                                    string.Format(CultureInfo.CurrentUICulture, CodeAnalysisResources.ResourceStreamEndedUnexpectedly, bytesWritten, count));
                         }
                         resourceWriter.Align(8);
                     }

src/Test/Utilities/Shared/Mocks/TestStream.cs

@@ -8,13 +8,19 @@ namespace Roslyn.Test.Utilities
     public class TestStream : Stream
     {
         private readonly bool _canRead, _canSeek, _canWrite;
-        private Func<byte[], int, int, int> _readFunc;
+        private readonly Func<byte[], int, int, int> _readFunc;
+        private readonly long _length;
+        private readonly Func<long> _getPosition;
+        private readonly Action<long> _setPosition;
 
         public TestStream(
             bool canRead = false,
             bool canSeek = false,
             bool canWrite = false,
-            Func<byte[], int, int, int> readFunc = null)
+            Func<byte[], int, int, int> readFunc = null,
+            long length = 0,
+            Func<long> getPosition = null,
+            Action<long> setPosition = null)
         {
             _canRead = canRead;
             _canSeek = canSeek;
@@ -22,6 +28,13 @@ public class TestStream : Stream
             _readFunc = readFunc != null
                 ? readFunc
                 : (_1, _2, _3) => { throw new NotImplementedException(); };
+            _length = length;
+            _getPosition = getPosition != null
+                ? getPosition
+                : () => { throw new NotImplementedException(); };
+            _setPosition = setPosition != null
+                ? setPosition
+                : (_1) => { throw new NotImplementedException(); };
         }
 
         public override bool CanRead => _canRead;
@@ -30,25 +43,12 @@ public class TestStream : Stream
 
         public override bool CanWrite => _canWrite;
 
-        public override long Length
-        {
-            get
-            {
-                throw new NotSupportedException();
-            }
-        }
+        public override long Length => _length;
 
         public override long Position
         {
-            get
-            {
-                throw new NotSupportedException();
-            }
-
-            set
-            {
-                throw new NotSupportedException();
-            }
+            get { return _getPosition(); }
+            set { _setPosition(value); }
         }
 
         public override void Flush()