WIP message suppression mechanism

compiler/src/dotty/tools/dotc/config/ScalaSettings.scala

@@ -54,8 +54,8 @@ class ScalaSettings extends Settings.SettingGroup {
   val plugin: Setting[List[String]]             = MultiStringSetting  ("-Xplugin", "paths", "Load a plugin from each classpath.")
   val disable: Setting[List[String]]            = MultiStringSetting  ("-Xplugin-disable", "plugin", "Disable plugins by name.")
   val require: Setting[List[String]]            = MultiStringSetting  ("-Xplugin-require", "plugin", "Abort if a named plugin is not loaded.")
-  val showPlugins: Setting[Boolean]        = BooleanSetting      ("-Xplugin-list", "Print a synopsis of loaded plugins.")
-  val pluginsDir: Setting[String]         = StringSetting       ("-Xpluginsdir", "path", "Path to search for plugin archives.", Defaults.scalaPluginPath)
+  val showPlugins: Setting[Boolean]             = BooleanSetting      ("-Xplugin-list", "Print a synopsis of loaded plugins.")
+  val pluginsDir: Setting[String]               = StringSetting       ("-Xpluginsdir", "path", "Path to search for plugin archives.", Defaults.scalaPluginPath)
   val pluginOptions: Setting[List[String]]      = MultiStringSetting  ("-P", "plugin:opt", "Pass an option to a plugin, e.g. -P:<plugin>:<opt>")
 
   /** -X "Advanced" settings
@@ -76,6 +76,8 @@ class ScalaSettings extends Settings.SettingGroup {
   val XreplLineWidth: Setting[Int] = IntSetting("-Xrepl-line-width", "Maximal number of columns per line for REPL output", 390)
   val XfatalWarnings: Setting[Boolean] = BooleanSetting("-Xfatal-warnings", "Fail the compilation if there are any warnings.")
   val XverifySignatures: Setting[Boolean] = BooleanSetting("-Xverify-signatures", "Verify generic signatures in generated bytecode.")
+  val XsuppressMessageIds: Setting[List[String]] = MultiStringSetting("-Xsuppress-message-ids", "ids", "Suppress warnings if errorId is in this setting")
+  val XsuppressWarningKinds: Setting[List[String]] = MultiStringSetting("-Xsuppress-warning-kinds", "kinds", "Suppress warnings if error kind is in this setting")
 
   /** -Y "Private" settings */
   val YoverrideVars: Setting[Boolean] = BooleanSetting("-Yoverride-vars", "Allow vars to be overridden.")
@@ -91,7 +93,7 @@ class ScalaSettings extends Settings.SettingGroup {
   val Ylog: Setting[List[String]] = PhasesSetting("-Ylog", "Log operations during")
   val YemitTastyInClass: Setting[Boolean] = BooleanSetting("-Yemit-tasty-in-class", "Generate tasty in the .class file and add an empty *.hasTasty file.")
   val YlogClasspath: Setting[Boolean] = BooleanSetting("-Ylog-classpath", "Output information about what classpath is being applied.")
-  val YdisableFlatCpCaching: Setting[Boolean]  = BooleanSetting("-YdisableFlatCpCaching", "Do not cache flat classpath representation of classpath elements from jars across compiler instances.")
+  val YdisableFlatCpCaching: Setting[Boolean] = BooleanSetting("-YdisableFlatCpCaching", "Do not cache flat classpath representation of classpath elements from jars across compiler instances.")
 
   val Yscala2Unpickler: Setting[String] = StringSetting("-Yscala2-unpickler", "", "Control where we may get Scala 2 symbols from. This is either \"always\", \"never\", or a classpath.", "always")
 

compiler/src/dotty/tools/dotc/reporting/Reporter.scala

@@ -36,30 +36,65 @@ object Reporter {
 
 trait Reporting { this: Context =>
 
+import dotty.tools.dotc.reporting.diagnostic.MessageContainer
+
+  type Escalation = MessageContainer => Option[MessageContainer]
+  val suppression: Escalation = (mc: MessageContainer) => for {
+    nonSilent <- silentWarnings(mc)
+    allowedId <- suppressIds(nonSilent)
+    allowedKind <- suppressKinds(allowedId)
+    escalated <- fatalWarnings(allowedKind)
+  } yield escalated
+
+  def suppressedIds: List[Int] = this.settings.XsuppressMessageIds.value
+    .flatMap(id => scala.util.Try(id.toInt).toOption)
+
+  def suppressIds(mc: MessageContainer) = {
+    val errornumber = mc.contained().errorId.errorNumber()
+    mc match {
+      case w: Error => Some(mc)
+      case m if suppressedIds.contains(m.contained().errorId.errorNumber()) => None
+      case _ => Some(mc)
+    }
+  }
+
+  def supressedWarningKinds: List[String] = this.settings.XsuppressWarningKinds.value
+  def suppressKinds(mc: MessageContainer) = mc match {
+    case w: Warning if supressedWarningKinds.contains(w.contained().kind) => None
+    case _ => Some(mc)
+  }
+
+  val silentWarnings: Escalation = (mc: MessageContainer) => mc match {
+    case _: Warning if this.settings.silentWarnings.value(this) => None
+    case _ => Some(mc)
+  }
+
+  val fatalWarnings: Escalation = (mc: MessageContainer) => mc match {
+    case w: Warning if this.settings.XfatalWarnings.value(this) => Some(w.toError)
+    case _ => Some(mc)
+  }
+
+
+  def report(cont: MessageContainer) = suppression(cont) foreach reporter.report _
+
   /** For sending messages that are printed only if -verbose is set */
   def inform(msg: => String, pos: SourcePosition = NoSourcePosition): Unit =
     if (this.settings.verbose.value) this.echo(msg, pos)
 
   def echo(msg: => String, pos: SourcePosition = NoSourcePosition): Unit =
-    reporter.report(new Info(msg, pos))
-
-  def reportWarning(warning: Warning): Unit =
-    if (!this.settings.silentWarnings.value) {
-      if (this.settings.XfatalWarnings.value) reporter.report(warning.toError)
-      else reporter.report(warning)
-    }
+    report(new Info(msg, pos))
 
   def deprecationWarning(msg: => Message, pos: SourcePosition = NoSourcePosition): Unit =
-    if (this.settings.deprecation.value) reportWarning(new DeprecationWarning(msg, pos))
+    report(new DeprecationWarning(msg, pos))
 
   def migrationWarning(msg: => Message, pos: SourcePosition = NoSourcePosition): Unit =
-    reportWarning(new MigrationWarning(msg, pos))
+    report(new MigrationWarning(msg, pos))
 
   def uncheckedWarning(msg: => Message, pos: SourcePosition = NoSourcePosition): Unit =
-    reportWarning(new UncheckedWarning(msg, pos))
+    report(new UncheckedWarning(msg, pos))
 
   def featureWarning(msg: => Message, pos: SourcePosition = NoSourcePosition): Unit =
-    reportWarning(new FeatureWarning(msg, pos))
+    report(new FeatureWarning(msg, pos))
 
   def featureWarning(feature: String, featureDescription: String, isScala2Feature: Boolean,
       featureUseSite: Symbol, required: Boolean, pos: SourcePosition): Unit = {
@@ -81,24 +116,25 @@ trait Reporting { this: Context =>
 
     val msg = s"$featureDescription $req be enabled\nby making the implicit value $fqname visible.$explain"
     if (required) error(msg, pos)
-    else reportWarning(new FeatureWarning(msg, pos))
+    else report(new FeatureWarning(msg, pos))
   }
 
   def warning(msg: => Message, pos: SourcePosition = NoSourcePosition): Unit =
-    reportWarning(new Warning(msg, pos))
+    report(new Warning(msg, pos))
+
 
   def strictWarning(msg: => Message, pos: SourcePosition = NoSourcePosition): Unit =
     if (this.settings.strict.value) error(msg, pos)
-    else reportWarning(new ExtendMessage(() => msg)(_ + "\n(This would be an error under strict mode)").warning(pos))
+    else report(new ExtendMessage(() => msg)(_ + "\n(This would be an error under strict mode)").warning(pos))
 
   def error(msg: => Message, pos: SourcePosition = NoSourcePosition): Unit =
-    reporter.report(new Error(msg, pos))
+    report(new Error(msg, pos))
 
   def errorOrMigrationWarning(msg: => Message, pos: SourcePosition = NoSourcePosition): Unit =
     if (ctx.scala2Mode) migrationWarning(msg, pos) else error(msg, pos)
 
   def restrictionError(msg: => Message, pos: SourcePosition = NoSourcePosition): Unit =
-    reporter.report {
+    report {
       new ExtendMessage(() => msg)(m => s"Implementation restriction: $m").error(pos)
     }
 

compiler/src/dotty/tools/dotc/reporting/diagnostic/ErrorMessageID.java

@@ -4,10 +4,9 @@
 public enum ErrorMessageID {
 
     // IMPORTANT: Add new IDs only at the end and never remove IDs
-
     LazyErrorId, // // errorNumber: -2
     NoExplanationID, // errorNumber: -1
-
+    // Note: line number n contains error number n - 10
     EmptyCatchOrFinallyBlockID, // errorNumber: 0
     EmptyCatchBlockID, // errorNumber: 1
     EmptyCatchAndFinallyBlockID, // errorNumber: 2