niti: Introduce a method to create and initialize a Frame

Signed-off-by: Julien Pagès <julien.projet@gmail.com>

diff --git a/src/interpreter/naive_interpreter.nit b/src/interpreter/naive_interpreter.nit
index 6333bc0..c92ba90 100644 (file)
--- a/src/interpreter/naive_interpreter.nit
+++ b/src/interpreter/naive_interpreter.nit
@@ -317,6 +317,15 @@ class NaiveInterpreter
                return frames.first.arguments.first.mtype.as(MClassType)
        end
 
+       # Initialize the environment for a call and return a new Frame
+       # *`node` The AST node
+       # *`mpropdef` The corresponding mpropdef
+       # *`args` Arguments of the call
+       fun new_frame(node: ANode, mpropdef: MPropDef, args: Array[Instance]): FRAME
+       do
+               return new Frame(node, mpropdef, args)
+       end
+
        # Exit the program with a message
        fun fatal(message: String)
        do
@@ -418,7 +427,7 @@ class NaiveInterpreter
                var node = modelbuilder.mpropdef2node(mpropdef)
                if mpropdef.is_abstract then
                        if node != null then
-                               self.frames.unshift new Frame(node, mpropdef, args)
+                               self.frames.unshift new_frame(node, mpropdef, args)
                        end
                        fatal("Abstract method `{mpropdef.mproperty.name}` called on `{args.first.mtype}`")
                        abort
@@ -714,7 +723,7 @@ redef class AMethPropdef
 
        redef fun call(v, mpropdef, args)
        do
-               var f = new Frame(self, self.mpropdef.as(not null), args)
+               var f = v.new_frame(self, mpropdef, args)
                var res = call_commons(v, mpropdef, args, f)
                v.frames.shift
                if v.returnmark == f then
@@ -1151,7 +1160,8 @@ redef class AAttrPropdef
                if mpropdef == mreadpropdef then
                        assert args.length == 1
                        if not is_lazy or v.isset_attribute(attr, recv) then return v.read_attribute(attr, recv)
-                       return evaluate_expr(v, recv)
+                       var f = v.new_frame(self, mpropdef, args)
+                       return evaluate_expr(v, recv, f)
                else if mpropdef == mwritepropdef then
                        assert args.length == 2
                        v.write_attribute(attr, recv, args[1])
@@ -1166,7 +1176,8 @@ redef class AAttrPropdef
        do
                if is_lazy then return
                if has_value then
-                       evaluate_expr(v, recv)
+                       var f = v.new_frame(self, mpropdef.as(not null), [recv])
+                       evaluate_expr(v, recv, f)
                        return
                end
                var mpropdef = self.mpropdef
@@ -1178,10 +1189,9 @@ redef class AAttrPropdef
                end
        end
 
-       private fun evaluate_expr(v: NaiveInterpreter, recv: Instance): Instance
+       private fun evaluate_expr(v: NaiveInterpreter, recv: Instance, f: Frame): Instance
        do
                assert recv isa MutableInstance
-               var f = new Frame(self, self.mpropdef.as(not null), [recv])
                v.frames.unshift(f)
 
                var val