Merge pull request #2365 from markus1189/nowarn

Add -nowarn option to silence warnings

Author: felixmulder

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

@@ -41,6 +41,7 @@ class ScalaSettings extends Settings.SettingGroup {
   val strict = BooleanSetting("-strict", "Use strict type rules, which means some formerly legal code does not typecheck anymore.")
   val language = MultiStringSetting("-language", "feature", "Enable one or more language features.")
   val rewrite = OptionSetting[Rewrites]("-rewrite", "When used in conjunction with -language:Scala2 rewrites sources to migrate to new syntax")
+  val silentWarnings = BooleanSetting("-nowarn", "Silence all warnings.")
 
   /** -X "Advanced" settings
    */

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

@@ -38,8 +38,10 @@ trait Reporting { this: Context =>
     reporter.report(new Info(msg, pos))
 
   def reportWarning(warning: Warning): Unit =
-    if (this.settings.XfatalWarnings.value) reporter.report(warning.toError)
-    else reporter.report(warning)
+    if (!this.settings.silentWarnings.value) {
+      if (this.settings.XfatalWarnings.value) reporter.report(warning.toError)
+      else  reporter.report(warning)
+    }
 
   def deprecationWarning(msg: => Message, pos: SourcePosition = NoSourcePosition): Unit =
     reportWarning(new DeprecationWarning(msg, pos))

compiler/test/dotty/tools/dotc/CompilationTests.scala

@@ -72,8 +72,13 @@ class CompilationTests extends ParallelTesting {
       scala2Mode
     ) +
     compileFilesInDir("../tests/new", defaultOptions) +
-    compileFilesInDir("../tests/pos-scala2", scala2Mode)
-    compileFilesInDir("../tests/pos", defaultOptions)
+    compileFilesInDir("../tests/pos-scala2", scala2Mode) +
+    compileFilesInDir("../tests/pos", defaultOptions) +
+    compileFile(
+      // succeeds despite -Xfatal-warnings because of -nowarn
+      "../tests/neg/customArgs/xfatalWarnings.scala",
+      defaultOptions.and("-nowarn", "-Xfatal-warnings")
+    )
   }.checkCompile()
 
   @Test def posTwice: Unit = {
@@ -239,7 +244,7 @@ class CompilationTests extends ParallelTesting {
     }.map(_.checkCompile()).foreach(_.delete())
   }
 
-  @Test def bytecodeIdemporency: Unit = {
+  @Test def bytecodeIdempotency: Unit = {
     var failed = 0
     var total = 0
     val blacklisted = Set(

compiler/test/dotty/tools/dotc/reporting/ErrorMessagesTest.scala

@@ -16,7 +16,6 @@ trait ErrorMessagesTest extends DottyTest {
   private def freshReporter(ctx: Context) =
     ctx.fresh.setReporter(new CapturingReporter)
 
-
   class Report(messages: List[Message], ictx: Context) {
     def expect(f: (Context, List[Message]) => Unit): Unit = {
       f(ictx, messages)