better error message for default arguments.

3 files changed, 23 insertions, 13 deletions

diff --git a/src/compiler/scala/tools/nsc/typechecker/Typers.scala b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
index a003a4fd7e..7dc2f56197 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Typers.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
@@ -2371,6 +2371,9 @@ trait Typers { self: Analyzer =>
                 val funSym = fun1 match { case Block(_, expr) => expr.symbol }
                 if (allArgs.length != args.length && callToCompanionConstr(context, funSym)) {
                   errorTree(tree, "module extending its companion class cannot use default constructor arguments")
+                } else if (allArgs.length > formals.length) {
+                  removeNames(Typer.this)(allArgs, params) // #3818
+                  setError(tree)
                 } else if (allArgs.length == formals.length) {
                   // useful when a default doesn't match parameter type, e.g. def f[T](x:T="a"); f[Int]()
                   val note = "Error occurred in an application involving default arguments."
diff --git a/test/files/neg/names-defaults-neg.check b/test/files/neg/names-defaults-neg.check
index 1f77b828b7..743496e0e1 100644
--- a/test/files/neg/names-defaults-neg.check
+++ b/test/files/neg/names-defaults-neg.check
@@ -119,44 +119,47 @@ names-defaults-neg.scala:93: warning: the parameter name y has been deprecated.
 names-defaults-neg.scala:93: error: parameter specified twice: b
   deprNam3(y = 10, b = 2)
                      ^
-names-defaults-neg.scala:127: error: reference to var2 is ambiguous; it is both, a parameter
+names-defaults-neg.scala:98: error: unknown parameter name: m
+  f3818(y = 1, m = 1)
+                 ^
+names-defaults-neg.scala:131: error: reference to var2 is ambiguous; it is both, a parameter
 name of the method and the name of a variable currently in scope.
   delay(var2 = 40)
              ^
-names-defaults-neg.scala:130: error: missing parameter type for expanded function ((x$1) => a = x$1)
+names-defaults-neg.scala:134: error: missing parameter type for expanded function ((x$1) => a = x$1)
   val taf2: Int => Unit = testAnnFun(a = _, b = get("+"))
                                          ^
-names-defaults-neg.scala:131: error: parameter specified twice: a
+names-defaults-neg.scala:135: error: parameter specified twice: a
   val taf3 = testAnnFun(b = _: String, a = get(8))
                                          ^
-names-defaults-neg.scala:132: error: wrong number of parameters; expected = 2
+names-defaults-neg.scala:136: error: wrong number of parameters; expected = 2
   val taf4: (Int, String) => Unit = testAnnFun(_, b = _)
                                               ^
-names-defaults-neg.scala:140: error: variable definition needs type because the name is used as named argument the definition.
+names-defaults-neg.scala:144: error: variable definition needs type because the name is used as named argument the definition.
   def t3 { var x = t.f(x = 1) }
                ^
-names-defaults-neg.scala:143: error: variable definition needs type because the name is used as named argument the definition.
+names-defaults-neg.scala:147: error: variable definition needs type because the name is used as named argument the definition.
   object t6 { var x = t.f(x = 1) }
                   ^
-names-defaults-neg.scala:146: error: variable definition needs type because the name is used as named argument the definition.
+names-defaults-neg.scala:150: error: variable definition needs type because the name is used as named argument the definition.
   class t9 { var x = t.f(x = 1) }
                  ^
-names-defaults-neg.scala:160: error: variable definition needs type because the name is used as named argument the definition.
+names-defaults-neg.scala:164: error: variable definition needs type because the name is used as named argument the definition.
   def u3 { var x = u.f(x = 1) }
                ^
-names-defaults-neg.scala:163: error: variable definition needs type because the name is used as named argument the definition.
+names-defaults-neg.scala:167: error: variable definition needs type because the name is used as named argument the definition.
   def u6 { var x = u.f(x = "32") }
                ^
-names-defaults-neg.scala:166: error: reference to x is ambiguous; it is both, a parameter
+names-defaults-neg.scala:170: error: reference to x is ambiguous; it is both, a parameter
 name of the method and the name of a variable currently in scope.
   def u9 { var x: Int = u.f(x = 1) }
                               ^
-names-defaults-neg.scala:173: error: variable definition needs type because the name is used as named argument the definition.
+names-defaults-neg.scala:177: error: variable definition needs type because the name is used as named argument the definition.
   class u15 { var x = u.f(x = 1) }
                   ^
-names-defaults-neg.scala:176: error: reference to x is ambiguous; it is both, a parameter
+names-defaults-neg.scala:180: error: reference to x is ambiguous; it is both, a parameter
 name of the method and the name of a variable currently in scope.
   class u18 { var x: Int = u.f(x = 1) }
                                  ^
 one warning found
-40 errors found
+41 errors found
diff --git a/test/files/neg/names-defaults-neg.scala b/test/files/neg/names-defaults-neg.scala
index 4350f9860d..9fbe554f0e 100644
--- a/test/files/neg/names-defaults-neg.scala
+++ b/test/files/neg/names-defaults-neg.scala
@@ -93,6 +93,10 @@ object Test extends Application {
   deprNam3(y = 10, b = 2)
 
 
+  // t3818
+  def f3818(x: Int = 1, y: Int, z: Int = 1) = 0
+  f3818(y = 1, m = 1)
+
   // DEFINITIONS
   def test1(a: Int, b: String) = a +": "+ b
   def test2(x: Unit) = println("test2")