typing: mark variable dirty on type_adaptation

Signed-off-by: Jean Privat <jean@pryen.org>

diff --git a/src/semantize/typing.nit b/src/semantize/typing.nit
index 8ca8c6e..3df5224 100644 (file)
--- a/src/semantize/typing.nit
+++ b/src/semantize/typing.nit
@@ -252,11 +252,11 @@ private class TypeVisitor
 
                # One is null (mtype2 see above) the other is not null
                if anode isa AEqExpr then
-                       anode.after_flow_context.when_true.set_var(variable, mtype2)
-                       anode.after_flow_context.when_false.set_var(variable, mtype)
+                       anode.after_flow_context.when_true.set_var(self, variable, mtype2)
+                       anode.after_flow_context.when_false.set_var(self, variable, mtype)
                else if anode isa ANeExpr then
-                       anode.after_flow_context.when_false.set_var(variable, mtype2)
-                       anode.after_flow_context.when_true.set_var(variable, mtype)
+                       anode.after_flow_context.when_false.set_var(self, variable, mtype2)
+                       anode.after_flow_context.when_true.set_var(self, variable, mtype)
                else
                        abort
                end
@@ -468,12 +468,15 @@ private class TypeVisitor
                end
        end
 
+       # Some variables where type-adapted during the visit
+       var dirty = false
+
        fun set_variable(node: AExpr, variable: Variable, mtype: nullable MType)
        do
                var flow = node.after_flow_context
                assert flow != null
 
-               flow.set_var(variable, mtype)
+               flow.set_var(self, variable, mtype)
        end
 
        fun merge_types(node: ANode, col: Array[nullable MType]): nullable MType
@@ -549,9 +552,12 @@ redef class FlowContext
        # Adapt the variable to a static type
        # Warning1: do not modify vars directly.
        # Warning2: sub-flow may have cached a unadapted variable
-       private fun set_var(variable: Variable, mtype: nullable MType)
+       private fun set_var(v: TypeVisitor, variable: Variable, mtype: nullable MType)
        do
+               if vars.has_key(variable) and vars[variable] == mtype then return
                self.vars[variable] = mtype
+               v.dirty = true
+               #node.debug "set {variable} to {mtype or else "X"}"
        end
 
        # Look in the flow and previous flow and collect all first reachable type adaptation of a local variable
@@ -1401,7 +1407,7 @@ redef class AIsaExpr
                        #var from = if orig != null then orig.to_s else "invalid"
                        #var to = if mtype != null then mtype.to_s else "invalid"
                        #debug("adapt {variable}: {from} -> {to}")
-                       self.after_flow_context.when_true.set_var(variable, mtype)
+                       self.after_flow_context.when_true.set_var(v, variable, mtype)
                end
 
                self.mtype = v.type_bool(self)