[nomaster] better error messages for various macro definition errors

backport of 1d3ec4e

src/compiler/scala/tools/nsc/typechecker/ContextErrors.scala

@@ -1294,7 +1294,7 @@ trait ContextErrors {
 
     private def compatibilityError(message: String) =
       implRefError(
-        "macro implementation has wrong shape:"+
+        "macro implementation has incompatible shape:"+
         "\n required: " + showMeth(rparamss, rret, abbreviate = true) +
         "\n found   : " + showMeth(aparamss, aret, abbreviate = false) +
         "\n" + message)
@@ -1328,15 +1328,19 @@ trait ContextErrors {
 
     def MacroImplOverloadedError() = implRefError("macro implementation cannot be overloaded")
 
-    def MacroImplWrongNumberOfTypeArgumentsError(macroImplRef: Tree) = implRefError(typer.TyperErrorGen.TypedApplyWrongNumberOfTpeParametersErrorMessage(macroImplRef))
+    def MacroImplWrongNumberOfTypeArgumentsError(macroImplRef: Tree) = {
+      val MacroImplReference(owner, meth, targs) = macroImplRef
+      val diagnostic = if (meth.typeParams.length > targs.length) "has too few type arguments" else "has too many arguments"
+      implRefError(s"macro implementation reference $diagnostic for " + treeSymTypeMsg(macroImplRef))
+    }
 
     def MacroImplNotStaticError() = implRefError("macro implementation must be in statically accessible object")
 
     // Phase III: check compatibility between the macro def and its macro impl
     // aXXX (e.g. aparams) => characteristics of the macro impl ("a" stands for "actual")
     // rXXX (e.g. rparams) => characteristics of a reference macro impl signature synthesized from the macro def ("r" stands for "reference")
 
-    def MacroImplNonTagImplicitParameters(params: List[Symbol]) = compatibilityError("macro implementations cannot have implicit parameters other than WeakTypeTag evidences")
+    def MacroImplNonTagImplicitParameters(params: List[Symbol]) = implRefError("macro implementations cannot have implicit parameters other than WeakTypeTag evidences")
 
     def MacroImplParamssMismatchError() = compatibilityError("number of parameter sections differ")
 

test/files/neg/macro-invalidimpl-f.check

@@ -1,4 +1,4 @@
-Macros_Test_2.scala:2: error: macro implementation has wrong shape:
+Macros_Test_2.scala:2: error: macro implementation has incompatible shape:
  required: (c: scala.reflect.macros.Context)(): c.Expr[Unit]
  found   : (c: scala.reflect.macros.Context): c.Expr[Unit]
 number of parameter sections differ

test/files/neg/macro-invalidimpl-g.check

@@ -1,4 +1,4 @@
-Macros_Test_2.scala:2: error: macro implementation has wrong shape:
+Macros_Test_2.scala:2: error: macro implementation has incompatible shape:
  required: (c: scala.reflect.macros.Context): c.Expr[Unit]
  found   : (c: scala.reflect.macros.Context)(): c.Expr[Unit]
 number of parameter sections differ

test/files/neg/macro-invalidret-nontree.check

@@ -1,4 +1,4 @@
-Macros_Test_2.scala:2: error: macro implementation has wrong shape:
+Macros_Test_2.scala:2: error: macro implementation has incompatible shape:
  required: (c: scala.reflect.macros.Context): c.Expr[Any]
  found   : (c: scala.reflect.macros.Context): Int
 type mismatch for return type: Int does not conform to c.Expr[Any]

test/files/neg/macro-invalidret-nonuniversetree.check

@@ -1,4 +1,4 @@
-Macros_Test_2.scala:2: error: macro implementation has wrong shape:
+Macros_Test_2.scala:2: error: macro implementation has incompatible shape:
  required: (c: scala.reflect.macros.Context): c.Expr[Any]
  found   : (c: scala.reflect.macros.Context): reflect.runtime.universe.Literal
 type mismatch for return type: reflect.runtime.universe.Literal does not conform to c.Expr[Any]

test/files/neg/macro-invalidsig-context-bounds.check

@@ -1,7 +1,4 @@
-Macros_Test_1.scala:2: error: macro implementation has wrong shape:
- required: (c: scala.reflect.macros.Context): c.Expr[Any]
- found   : (c: scala.reflect.macros.Context)(implicit evidence$2: Numeric[U]): c.universe.Literal
-macro implementations cannot have implicit parameters other than WeakTypeTag evidences
+Macros_Test_1.scala:2: error: macro implementations cannot have implicit parameters other than WeakTypeTag evidences
   def foo[U] = macro Impls.foo[U]
                            ^
 one error found

test/files/neg/macro-invalidsig-ctx-badargc.check

@@ -1,4 +1,4 @@
-Macros_Test_2.scala:2: error: macro implementation has wrong shape:
+Macros_Test_2.scala:2: error: macro implementation has incompatible shape:
  required: (c: scala.reflect.macros.Context): c.Expr[Any]
  found   : : Nothing
 number of parameter sections differ

test/files/neg/macro-invalidsig-ctx-badtype.check

@@ -1,4 +1,4 @@
-Macros_Test_2.scala:2: error: macro implementation has wrong shape:
+Macros_Test_2.scala:2: error: macro implementation has incompatible shape:
  required: (c: scala.reflect.macros.Context): c.Expr[Any]
  found   : (c: scala.reflect.api.Universe): Nothing
 type mismatch for parameter c: scala.reflect.macros.Context does not conform to scala.reflect.api.Universe

test/files/neg/macro-invalidsig-ctx-badvarargs.check

@@ -1,4 +1,4 @@
-Macros_Test_2.scala:2: error: macro implementation has wrong shape:
+Macros_Test_2.scala:2: error: macro implementation has incompatible shape:
  required: (c: scala.reflect.macros.Context): c.Expr[Any]
  found   : (cs: scala.reflect.macros.Context*): Nothing
 types incompatible for parameter cs: corresponding is not a vararg parameter

test/files/neg/macro-invalidsig-ctx-noctx.check

@@ -1,4 +1,4 @@
-Macros_Test_2.scala:2: error: macro implementation has wrong shape:
+Macros_Test_2.scala:2: error: macro implementation has incompatible shape:
  required: (c: scala.reflect.macros.Context)(x: c.Expr[Any]): c.Expr[Any]
  found   : (c: scala.reflect.macros.Context): Nothing
 number of parameter sections differ

test/files/neg/macro-invalidsig-implicit-params.check

@@ -1,7 +1,4 @@
-Impls_Macros_1.scala:18: error: macro implementation has wrong shape:
- required: (c: scala.reflect.macros.Context)(x: c.Expr[Int]): c.Expr[Unit]
- found   : (c: scala.reflect.macros.Context)(implicit x: c.Expr[Int]): c.Expr[Unit]
-macro implementations cannot have implicit parameters other than WeakTypeTag evidences
+Impls_Macros_1.scala:18: error: macro implementations cannot have implicit parameters other than WeakTypeTag evidences
   def foo_targs[U](x: Int) = macro Impls.foo_targs[T, U]
                                          ^
 one error found

test/files/neg/macro-invalidsig-params-badargc.check

@@ -1,4 +1,4 @@
-Impls_Macros_1.scala:8: error: macro implementation has wrong shape:
+Impls_Macros_1.scala:8: error: macro implementation has incompatible shape:
  required: (c: scala.reflect.macros.Context)(x: c.Expr[Int]): c.Expr[Any]
  found   : (c: scala.reflect.macros.Context)(x: c.Expr[Int], y: c.Expr[Int]): Nothing
 parameter lists have different length, found extra parameter y: c.Expr[Int]

test/files/neg/macro-invalidsig-params-badtype.check

@@ -1,4 +1,4 @@
-Impls_Macros_1.scala:8: error: macro implementation has wrong shape:
+Impls_Macros_1.scala:8: error: macro implementation has incompatible shape:
  required: (c: scala.reflect.macros.Context)(x: c.Expr[Int]): c.Expr[Any]
  found   : (c: scala.reflect.macros.Context)(x: c.universe.Tree): Nothing
 type mismatch for parameter x: c.Expr[Int] does not conform to c.universe.Tree

test/files/neg/macro-invalidsig-params-badvarargs.check

@@ -1,4 +1,4 @@
-Impls_Macros_1.scala:8: error: macro implementation has wrong shape:
+Impls_Macros_1.scala:8: error: macro implementation has incompatible shape:
  required: (c: scala.reflect.macros.Context)(x: c.Expr[Int], y: c.Expr[Int]): c.Expr[Any]
  found   : (c: scala.reflect.macros.Context)(xs: c.Expr[Int]*): Nothing
 parameter lists have different length, required extra parameter y: c.Expr[Int]

test/files/neg/macro-invalidsig-params-namemismatch.check

@@ -1,4 +1,4 @@
-Impls_Macros_1.scala:8: error: macro implementation has wrong shape:
+Impls_Macros_1.scala:8: error: macro implementation has incompatible shape:
  required: (c: scala.reflect.macros.Context)(x: c.Expr[Int], y: c.Expr[Int]): c.Expr[Any]
  found   : (c: scala.reflect.macros.Context)(y: c.Expr[Int], x: c.Expr[Int]): Nothing
 parameter names differ: x != y

test/files/neg/macro-invalidsig-tparams-badtype.check

@@ -1,4 +1,4 @@
-Macros_Test_2.scala:2: error: macro implementation has wrong shape:
+Macros_Test_2.scala:2: error: macro implementation has incompatible shape:
  required: (c: scala.reflect.macros.Context): c.Expr[Any]
  found   : (c: scala.reflect.macros.Context)(U: c.universe.Type): Nothing
 number of parameter sections differ

test/files/neg/macro-invalidsig-tparams-notparams-a.check

@@ -1,4 +1,4 @@
-Macros_Test_2.scala:2: error: wrong number of type parameters for method foo: [U](c: scala.reflect.macros.Context)(implicit evidence$1: c.WeakTypeTag[U])Nothing
+Macros_Test_2.scala:2: error: macro implementation reference has too few type arguments for method foo: [U](c: scala.reflect.macros.Context)(implicit evidence$1: c.WeakTypeTag[U])Nothing
   def foo = macro Impls.foo
                         ^
 one error found

test/files/neg/macro-invalidsig-tparams-notparams-b.check

@@ -1,4 +1,4 @@
-Macros_Test_2.scala:3: error: wrong number of type parameters for method foo: [T, U, V](c: scala.reflect.macros.Context)(implicit evidence$1: c.WeakTypeTag[T], implicit evidence$2: c.WeakTypeTag[U], implicit V: c.WeakTypeTag[V])c.Expr[Unit]
+Macros_Test_2.scala:3: error: macro implementation reference has too few type arguments for method foo: [T, U, V](c: scala.reflect.macros.Context)(implicit evidence$1: c.WeakTypeTag[T], implicit evidence$2: c.WeakTypeTag[U], implicit V: c.WeakTypeTag[V])c.Expr[Unit]
     def foo[V] = macro Impls.foo
                              ^
 one error found

test/files/neg/t5689.check

@@ -1,4 +1,4 @@
-t5689.scala:4: error: macro implementation has wrong shape:
+t5689.scala:4: error: macro implementation has incompatible shape:
  required: (c: scala.reflect.macros.Context)(i: c.Expr[Double]): c.Expr[String]
  found   : (c: scala.reflect.macros.Context)(i: c.Expr[Double]): c.Expr[Int]
 type mismatch for return type: c.Expr[Int] does not conform to c.Expr[String]