Allow for importing methods (#3633)

Importing individual methods didn't work as advertised because parser
would allow them but later drop that information. This slipped by because we never had mixed atoms and methods in stdlib.

# Important Notes
Added some basic tests but we need to ensure that the new parser allows for this.
@jdunkerley will be adding some changes to stdlib that will be testing this functionality as well.

CHANGELOG.md

@@ -302,6 +302,7 @@
 - [Explicit `self`][3569]
 - [Added benchmarking tool for the language server][3578]
 - [Support module imports using a qualified name][3608]
+- [Support importing module methods][3633]
 
 [3227]: https://github.com/enso-org/enso/pull/3227
 [3248]: https://github.com/enso-org/enso/pull/3248
@@ -338,6 +339,7 @@
 [3538]: https://github.com/enso-org/enso/pull/3569
 [3578]: https://github.com/enso-org/enso/pull/3578
 [3608]: https://github.com/enso-org/enso/pull/3608
+[3633]: https://github.com/enso-org/enso/pull/3633
 
 # Enso 2.0.0-alpha.18 (2021-10-12)
 

engine/runtime/src/test/scala/org/enso/compiler/test/codegen/AstToIrTest.scala

@@ -1048,6 +1048,8 @@ class AstToIrTest extends CompilerTest with Inside {
         "from project import all",
         "from Username.Bar.Quux import Baz",
         "from Username.Bar.Test import Baz, Spam",
+        "from Username.Bar.Test import Baz, Spam, foo, Bar",
+        "from Username.Bar.Test import foo, bar",
         "from username.Foo.Bar import all",
         "from username.Foo.Bar as Eggs import all hiding Spam",
         "from project.Foo.Bar import all hiding Spam, Eggs"

lib/scala/syntax/definition/src/main/scala/org/enso/syntax/text/AST.scala

@@ -345,8 +345,8 @@ object Shape extends ShapeImplicit {
     path: List1[AST.Ident],
     rename: Option[AST.Ident.Cons],
     isAll: Boolean,
-    onlyNames: Option[List1[AST.Ident.Cons]],
-    hidingNames: Option[List1[AST.Ident.Cons]]
+    onlyNames: Option[List1[AST.Ident]],
+    hidingNames: Option[List1[AST.Ident]]
   ) extends SpacelessAST[T]
   final case class Export[T](
     path: List1[AST.Ident],
@@ -2395,8 +2395,8 @@ object AST {
       path: List1[AST.Ident],
       rename: Option[AST.Ident.Cons],
       isAll: Boolean,
-      onlyNames: Option[List1[AST.Ident.Cons]],
-      hidingNames: Option[List1[AST.Ident.Cons]]
+      onlyNames: Option[List1[AST.Ident]],
+      hidingNames: Option[List1[AST.Ident]]
     ): Import =
       Shape.Import[AST](path, rename, isAll, onlyNames, hidingNames)
     def unapply(t: AST): Option[
@@ -2404,8 +2404,8 @@ object AST {
         List1[AST.Ident],
         Option[AST.Ident.Cons],
         Boolean,
-        Option[List1[AST.Ident.Cons]],
-        Option[List1[AST.Ident.Cons]]
+        Option[List1[AST.Ident]],
+        Option[List1[AST.Ident]]
       )
     ] =
       Unapply[Import].run(t =>

lib/scala/syntax/definition/src/main/scala/org/enso/syntax/text/ast/meta/Builtin.scala

@@ -289,6 +289,11 @@ object Builtin {
         (name, rename)
       }
 
+      val consOrVar: PartialFunction[AST, AST.Ident] = {
+        case AST.Ident.Var.any(v)  => v: AST.Ident
+        case AST.Ident.Cons.any(c) => c: AST.Ident
+      }
+
       val itemsImport = {
         val all: Pattern = Var("all")
         val items        = Pattern.SepList(Pattern.Cons() | Pattern.Var(), Opr(","))
@@ -305,13 +310,14 @@ object Builtin {
                 case Match.Or(_, Left(hidden)) =>
                   val hiddenItems = hidden.toStream
                     .map(_.wrapped)
-                    .flatMap(AST.Ident.Cons.any.unapply)
+                    .drop(2)
+                    .collect(consOrVar)
                   (List1(hiddenItems), None)
 
                 case Match.Or(_, Right(imported)) =>
                   val importedItems = imported.toStream
                     .map(_.wrapped)
-                    .flatMap(AST.Ident.Cons.any.unapply)
+                    .collect(consOrVar)
                   (None, List1(importedItems))
                 case _ => internalError
               }
@@ -339,19 +345,13 @@ object Builtin {
                   val hiddenItems = hidden.toStream
                     .map(_.wrapped)
                     .drop(2)
-                    .collect {
-                      case AST.Ident.Var.any(v)  => v: AST.Ident
-                      case AST.Ident.Cons.any(c) => c: AST.Ident
-                    }
+                    .collect(consOrVar)
                   (List1(hiddenItems), None)
 
                 case Match.Or(_, Right(imported)) =>
                   val importedItems = imported.toStream
                     .map(_.wrapped)
-                    .collect {
-                      case AST.Ident.Var.any(v)  => v: AST.Ident
-                      case AST.Ident.Cons.any(c) => c: AST.Ident
-                    }
+                    .collect(consOrVar)
                   (None, List1(importedItems))
                 case _ => internalError
               }

test/Tests/src/Semantic/Names_Spec.enso

@@ -1,6 +1,7 @@
 from Standard.Base import all
 
-from project.Semantic.Names.Definitions import another_method, another_constant, method_with_local_vars
+from project.Semantic.Names.Definitions import another_method, another_constant, method_with_local_vars, Bar
+import project.Semantic.Names.Definitions
 
 import Standard.Test