Implement /NoWarn switch

Warnings are logged as low importance messages instead.  This way they can still be seen with more verbosity but are essentially suppressed.

Closes dotnet#68

ref/net46/Microsoft.Build/Microsoft.Build.cs

@@ -939,6 +939,7 @@ public partial class BuildParameters
         public System.Globalization.CultureInfo UICulture { get { throw null; } set { } }
         public bool UseSynchronousLogging { get { throw null; } set { } }
         public System.Collections.Generic.ISet<string> WarningsAsErrors { get { throw null; } set { } }
+        public System.Collections.Generic.ISet<string> WarningsAsMessages { get { throw null; } set { } }
         public Microsoft.Build.Execution.BuildParameters Clone() { throw null; }
         public Microsoft.Build.Evaluation.Toolset GetToolset(string toolsVersion) { throw null; }
     }

src/XMakeBuildEngine/BackEnd/BuildManager/BuildManager.cs

@@ -424,7 +424,7 @@ public void BeginBuild(BuildParameters parameters)
                 }
 
                 // Set up the logging service.
-                ILoggingService loggingService = CreateLoggingService(_buildParameters.Loggers, _buildParameters.ForwardingLoggers, _buildParameters.WarningsAsErrors);
+                ILoggingService loggingService = CreateLoggingService(_buildParameters.Loggers, _buildParameters.ForwardingLoggers, _buildParameters.WarningsAsErrors, _buildParameters.WarningsAsMessages);
 
                 _nodeManager.RegisterPacketHandler(NodePacketType.LogMessage, LogMessagePacket.FactoryForDeserialization, loggingService as INodePacketHandler);
                 try
@@ -1736,7 +1736,7 @@ private void OnProjectStarted(object sender, ProjectStartedEventArgs e)
         /// <summary>
         /// Creates a logging service around the specified set of loggers.
         /// </summary>
-        private ILoggingService CreateLoggingService(IEnumerable<ILogger> loggers, IEnumerable<ForwardingLoggerRecord> forwardingLoggers, ISet<string> warningsAsErrors)
+        private ILoggingService CreateLoggingService(IEnumerable<ILogger> loggers, IEnumerable<ForwardingLoggerRecord> forwardingLoggers, ISet<string> warningsAsErrors, ISet<string> warningsAsMessages)
         {
             int cpuCount = _buildParameters.MaxNodeCount;
 
@@ -1764,6 +1764,7 @@ private ILoggingService CreateLoggingService(IEnumerable<ILogger> loggers, IEnum
             loggingService.OnProjectStarted += _projectStartedEventHandler;
             loggingService.OnProjectFinished += _projectFinishedEventHandler;
             loggingService.WarningsAsErrors = warningsAsErrors;
+            loggingService.WarningsAsMessages = warningsAsMessages;
 
             try
             {

src/XMakeBuildEngine/BackEnd/BuildManager/BuildParameters.cs

@@ -205,6 +205,11 @@ public class BuildParameters : INodePacketTranslatable
         /// </summary>
         private ISet<string> _warningsAsErrors = null;
 
+        /// <summary>
+        /// A list of warnings to treat as low importance messages.
+        /// </summary>
+        private ISet<string> _warningsAsMessages = null;
+
         /// <summary>
         /// The location of the toolset definitions.
         /// </summary>
@@ -326,6 +331,7 @@ private BuildParameters(BuildParameters other)
             _logTaskInputs = other._logTaskInputs;
             _logInitialPropertiesAndItems = other._logInitialPropertiesAndItems;
             _warningsAsErrors = other._warningsAsErrors == null ? null : new HashSet<string>(other._warningsAsErrors, StringComparer.OrdinalIgnoreCase);
+            _warningsAsMessages = other._warningsAsMessages == null ? null : new HashSet<string>(other._warningsAsMessages, StringComparer.OrdinalIgnoreCase);
         }
 
 #if FEATURE_THREAD_PRIORITY
@@ -598,6 +604,15 @@ public ISet<string> WarningsAsErrors
             set { _warningsAsErrors = value; }
         }
 
+        /// <summary>
+        /// A list of warnings to treat as low importance messages.
+        /// </summary>
+        public ISet<string> WarningsAsMessages
+        {
+            get { return _warningsAsMessages; }
+            set { _warningsAsMessages = value; }
+        }
+
         /// <summary>
         /// Locations to search for toolsets.
         /// </summary>

src/XMakeBuildEngine/BackEnd/Components/Logging/BuildEventArgTransportSink.cs

@@ -90,6 +90,16 @@ public ISet<string> WarningsAsErrors
             set;
         }
 
+        /// <summary>
+        /// This property is ignored by this event sink and relies on the receiver to treat warnings as low importance messages.
+        /// </summary>
+        public ISet<string> WarningsAsMessages
+        {
+            get;
+            set;
+        }
+
+
         /// <summary>
         /// This property is ignored by this event sink and relies on the receiver to keep track of whether or not any errors have been logged.
         /// </summary>

src/XMakeBuildEngine/BackEnd/Components/Logging/EventSourceSink.cs

@@ -140,6 +140,15 @@ public ISet<string> WarningsAsErrors
             set;
         }
 
+        /// <summary>
+        /// A list of warnings to treat as low importance messages.
+        /// </summary>
+        public ISet<string> WarningsAsMessages
+        {
+            get;
+            set;
+        }
+
         /// <summary>
         /// A list of build submission IDs that have logged errors.  If an error is logged outside of a submission, the submission ID is <see cref="BuildEventContext.InvalidSubmissionId"/>.
         /// </summary>
@@ -224,9 +233,33 @@ public void Consume(BuildEventArgs buildEvent)
             {
                 BuildWarningEventArgs warningEvent = (BuildWarningEventArgs) buildEvent;
 
-                // Treat this warning as an error if an empty set of warnings was specified or this code was specified
-                if (WarningsAsErrors != null && (WarningsAsErrors.Count == 0 || WarningsAsErrors.Contains(warningEvent.Code)))
+                if (WarningsAsMessages != null && WarningsAsMessages.Contains(warningEvent.Code))
+                {
+                    // Treat this warning as a message with low importance if its in the list
+                    BuildMessageEventArgs errorEvent = new BuildMessageEventArgs(
+                        warningEvent.Subcategory,
+                        warningEvent.Code,
+                        warningEvent.File,
+                        warningEvent.LineNumber,
+                        warningEvent.ColumnNumber,
+                        warningEvent.EndLineNumber,
+                        warningEvent.EndColumnNumber,
+                        warningEvent.Message,
+                        warningEvent.HelpKeyword,
+                        warningEvent.SenderName,
+                        MessageImportance.Low,
+                        warningEvent.Timestamp)
+                    {
+                        BuildEventContext = warningEvent.BuildEventContext,
+                        ProjectFile = warningEvent.ProjectFile,
+                    };
+
+                    this.RaiseMessageEvent(null, errorEvent);
+
+                }
+                else if (WarningsAsErrors != null && (WarningsAsErrors.Count == 0 || WarningsAsErrors.Contains(warningEvent.Code)))
                 {
+                    // Treat this warning as an error if an empty set of warnings was specified or this code was specified
                     BuildErrorEventArgs errorEvent = new BuildErrorEventArgs(
                         warningEvent.Subcategory,
                         warningEvent.Code,

src/XMakeBuildEngine/BackEnd/Components/Logging/ILoggingService.cs

@@ -162,6 +162,15 @@ ISet<string> WarningsAsErrors
             get;
             set;
         }
+
+        /// <summary>
+        /// A list of warnings to treat as low importance messages.
+        /// </summary>
+        ISet<string> WarningsAsMessages
+        {
+            get;
+            set;
+        }
         #endregion
 
         /// <summary>
@@ -472,6 +481,15 @@ ISet<string> WarningsAsErrors
             set;
         }
 
+        /// <summary>
+        /// A list of warnings to treat as low importance messages.
+        /// </summary>
+        ISet<string> WarningsAsMessages
+        {
+            get;
+            set;
+        }
+
         /// <summary>
         /// A list of build submissions that have logged errors.
         /// </summary>

src/XMakeBuildEngine/BackEnd/Components/Logging/LoggingService.cs

@@ -224,6 +224,11 @@ internal partial class LoggingService : ILoggingService, INodePacketHandler, IBu
         /// </summary>
         private ISet<string> _warningsAsErrors = null;
 
+        /// <summary>
+        /// A list of warnings to treat as low importance messages.
+        /// </summary>
+        private ISet<string> _warningsAsMessages = null;
+
         #endregion
 
         #endregion
@@ -459,6 +464,15 @@ public ISet<string> WarningsAsErrors
             set { _warningsAsErrors = value; }
         }
 
+        /// <summary>
+        /// A list of warnings to treat as low importance messages.
+        /// </summary>
+        public ISet<string> WarningsAsMessages
+        {
+            get { return _warningsAsMessages; }
+            set { _warningsAsMessages = value; }
+        }
+
         /// <summary>
         /// Determines if the specified submission has logged an errors.
         /// </summary>
@@ -819,7 +833,8 @@ public bool RegisterDistributedLogger(ILogger centralLogger, LoggerDescription f
                 // create an eventSourceSink which the central logger will register with to receive the events from the forwarding logger
                 EventSourceSink eventSourceSink = new EventSourceSink
                 {
-                    WarningsAsErrors = WarningsAsErrors == null ? null : new HashSet<string>(WarningsAsErrors, StringComparer.OrdinalIgnoreCase)
+                    WarningsAsErrors = WarningsAsErrors == null ? null : new HashSet<string>(WarningsAsErrors, StringComparer.OrdinalIgnoreCase),
+                    WarningsAsMessages = WarningsAsMessages == null ? null : new HashSet<string>(WarningsAsMessages, StringComparer.OrdinalIgnoreCase),
                 };
 
                 // If the logger is already in the list it should not be registered again.
@@ -1135,7 +1150,8 @@ private void CreateFilterEventSource()
                 _filterEventSource = new EventSourceSink
                 {
                     Name = "Sink for Distributed/Filter loggers",
-                    WarningsAsErrors = WarningsAsErrors == null ? null : new HashSet<string>(WarningsAsErrors, StringComparer.OrdinalIgnoreCase)
+                    WarningsAsErrors = WarningsAsErrors == null ? null : new HashSet<string>(WarningsAsErrors, StringComparer.OrdinalIgnoreCase),
+                    WarningsAsMessages = WarningsAsMessages == null ? null : new HashSet<string>(WarningsAsMessages, StringComparer.OrdinalIgnoreCase),
                 };
             }
         }

src/XMakeBuildEngine/UnitTests/BackEnd/MockLoggingService.cs

@@ -156,6 +156,14 @@ public ISet<string> WarningsAsErrors
             set;
         }
 
+        /// <summary>
+        /// List of warnings to treat as low importance messages.
+        /// </summary>
+        public ISet<string> WarningsAsMessages
+        {
+            get;
+            set;
+        }
 
         /// <summary>
         /// Is the logging service on a remote node, this is used to determine if properties need to be serialized

src/XMakeCommandLine/CommandLineSwitches.cs

@@ -103,6 +103,7 @@ internal enum ParameterizedSwitch
             ServerToClientPipeHandle,
 #endif
             WarningsAsErrors,
+            WarningsAsMessages,
             NumberOfParameterizedSwitches
         }
 
@@ -281,6 +282,7 @@ bool emptyParametersAllowed
             new ParameterizedSwitchInfo(  new string[] { "serverToClientPipeHandle", "s2c" },   ParameterizedSwitch.ServerToClientPipeHandle,   null,                           false,          null,                                  true,   false  ),
 #endif
             new ParameterizedSwitchInfo(  new string[] { "warnaserror", "err" },                ParameterizedSwitch.WarningsAsErrors,           null,                           true,           null,                                  true,   true  ),
+            new ParameterizedSwitchInfo(  new string[] { "warnasmessage", "nowarn" },           ParameterizedSwitch.WarningsAsMessages,         null,                           true,           "MissingWarnAsMessageParameterError",  true,   false ),
         };
 
         /// <summary>

src/XMakeCommandLine/Resources/Strings.resx

@@ -589,7 +589,22 @@ Copyright (C) Microsoft Corporation. All rights reserved.
                      build will fail.
     </value>
     <comment>
-      LOCALIZATION: "warnaserror" should not be localized.
+      LOCALIZATION: "/warnaserror" and "/err" should not be localized.
+      LOCALIZATION: None of the lines should be longer than a standard width console window, eg 80 chars.
+    </comment>
+  </data>
+  <data name="HelpMessage_29_WarnAsMessageSwitch" UESanitized="false" Visibility="Public">
+    <value>  /warnasmessage[:code[;code2]]
+                     List of warning codes to treats as low importance
+                     messages.  Use a semicolon or a comma to separate
+                     multiple warning codes.
+                     (Short form: /nowarn[:c;[c2]])
+
+                     Example:
+                       /warnasmessage:MSB3026
+    </value>
+    <comment>
+      LOCALIZATION: "/warnasmessage" and "/nowarn" should not be localized.
       LOCALIZATION: None of the lines should be longer than a standard width console window, eg 80 chars.
     </comment>
   </data>
@@ -963,11 +978,19 @@ Copyright (C) Microsoft Corporation. All rights reserved.
     <value>{0} ({1},{2})</value>
     <comment>A file location to be embedded in a string.</comment>
   </data>
+  <data name="MissingWarnAsMessageParameterError" UESanitized="true" Visibility="Public">
+    <value>MSBUILD : error MSB1050: Specify one or more warning codes to treat as low importance messages when using the /warnasmessage switch.</value>
+    <comment>
+      {StrBegin="MSBUILD : error MSB1050: "}
+      UE: This happens if the user does something like "msbuild.exe /warnasmessage:" without any codes.
+      LOCALIZATION: The prefix "MSBUILD : error MSBxxxx:" should not be localized.
+    </comment>
+  </data>
 
     <!--
         The command line message bucket is: MSB1001 - MSB1999
 
-        Next error code should be MSB1050.
+        Next error code should be MSB1051.
 
         Don't forget to update this comment after using the new code.
   -->

src/XMakeCommandLine/UnitTests/CommandLineSwitches_Tests.cs

@@ -1123,7 +1123,8 @@ public void InvalidToolsVersionErrors()
                                         new StringWriter(),
                                         false,
                                         false, 
-                                        warningsAsErrors: null);
+                                        warningsAsErrors: null,
+                                        warningsAsMessages: null);
                 }
                 finally
                 {