Fix overload resolution to accept unknown (empty) type arguments

typecheck methods for Instance, Interface, Singleton, Tuple, Record,
and Symbol literal types returned false for empty vertices (untyped
arguments with no callers), causing "failed to resolve overloads"
errors for calls like `raise unknown`. This was inconsistent with
Bool/Nil typecheck which already returned true for empty vertices.

Now all these methods distinguish "no types seen" (return true,
optimistic) from "types seen but none matched" (return false, real
error). Re-evaluation edges ensure correct matching when types arrive.

Author: mame

lib/typeprof/core/ast/sig_type.rb

@@ -2,7 +2,9 @@ module TypeProf::Core
   class AST
     def self.typecheck_for_module(genv, changes, f_mod, f_args, a_vtx, subst)
       changes.add_edge(genv, a_vtx, changes.target)
+      found_any = false
       a_vtx.each_type do |ty|
+        found_any = true
         ty = ty.base_type(genv)
         while ty
           if ty.mod == f_mod && ty.is_a?(Type::Instance)
@@ -25,7 +27,7 @@ def self.typecheck_for_module(genv, changes, f_mod, f_args, a_vtx, subst)
           ty = genv.get_superclass_type(ty, changes, {})
         end
       end
-      return false
+      return !found_any
     end
 
     def self.typecheck_for_prepended_modules(genv, changes, a_ty, f_mod, f_args, subst)
@@ -593,7 +595,9 @@ def typecheck(genv, changes, vtx, subst)
         return unless cpath
         f_mod = genv.resolve_cpath(cpath)
         changes.add_edge(genv, vtx, changes.target)
+        found_any = false
         vtx.each_type do |ty|
+          found_any = true
           case ty
           when Type::Singleton
             if f_mod.module?
@@ -608,7 +612,7 @@ def typecheck(genv, changes, vtx, subst)
             end
           end
         end
-        false
+        !found_any
       end
 
       def show
@@ -729,7 +733,9 @@ def contravariant_vertex0(genv, changes, vtx, subst)
 
       def typecheck(genv, changes, vtx, subst)
         changes.add_edge(genv, vtx, changes.target)
+        found_any = false
         vtx.each_type do |ty|
+          found_any = true
           case ty
           when Type::Array
             next if ty.elems.size != @types.size
@@ -744,7 +750,7 @@ def typecheck(genv, changes, vtx, subst)
             return true
           end
         end
-        false
+        !found_any
       end
 
       def show
@@ -799,7 +805,9 @@ def contravariant_vertex0(genv, changes, vtx, subst)
 
       def typecheck(genv, changes, vtx, subst)
         changes.add_edge(genv, vtx, changes.target)
+        found_any = false
         vtx.each_type do |ty|
+          found_any = true
           case ty
           when Type::Hash
             @fields.each do |key, field_node|
@@ -809,7 +817,7 @@ def typecheck(genv, changes, vtx, subst)
             return true
           end
         end
-        false
+        !found_any
       end
 
       def show
@@ -915,13 +923,15 @@ def contravariant_vertex0(genv, changes, vtx, subst)
       def typecheck(genv, changes, vtx, subst)
         if @lit.is_a?(::Symbol)
           changes.add_edge(genv, vtx, changes.target)
+          found_any = false
           vtx.each_type do |ty|
+            found_any = true
             case ty
             when Type::Symbol
               return true if ty.sym == @lit
             end
           end
-          return false
+          return !found_any
         end
         f_mod = get_type(genv).mod
         AST.typecheck_for_module(genv, changes, f_mod, [], vtx, subst)

scenario/control/raise-unknown.rb

@@ -0,0 +1,6 @@
+## update
+def foobarbaz(unknown)
+  raise unknown
+end
+
+## diagnostics

scenario/rbs/type-alias.rb

@@ -26,7 +26,6 @@ def test3: (untyped) -> (Integer | String)
 end
 
 ## diagnostics: test.rb
-(10,10)-(10,13): wrong type of arguments
 
 ## update: test.rbs
 type a = Integer
@@ -44,7 +43,6 @@ def test3: (untyped) -> Integer
 
 ## diagnostics: test.rb
 (6,10)-(6,13): wrong type of arguments
-(10,10)-(10,13): wrong type of arguments
 
 ## update: test.rbs
 type a = Integer
@@ -61,7 +59,6 @@ def test3: (untyped) -> Integer
 
 ## diagnostics: test.rb
 (6,10)-(6,13): wrong type of arguments
-(10,10)-(10,13): wrong type of arguments
 
 ## update: test.rbs
 class Bar
@@ -80,4 +77,3 @@ def test3: (untyped) -> Integer
 
 ## diagnostics: test.rb
 (6,10)-(6,13): wrong type of arguments
-(10,10)-(10,13): wrong type of arguments

scenario/rbs/untyped-for-overload-record.rb

@@ -0,0 +1,17 @@
+## update: test.rbs
+class C
+  def foo: ({ name: String }) -> :record
+         | (String) -> :str
+end
+
+## update: test.rb
+def check(unknown)
+  C.new.foo(unknown)
+end
+
+## diagnostics: test.rb
+
+## assert
+class Object
+  def check: (untyped) -> (:record | :str)
+end

scenario/rbs/untyped-for-overload-singleton.rb

@@ -0,0 +1,17 @@
+## update: test.rbs
+class C
+  def foo: (singleton(String)) -> :str
+         | (singleton(Integer)) -> :int
+end
+
+## update: test.rb
+def check(unknown)
+  C.new.foo(unknown)
+end
+
+## diagnostics: test.rb
+
+## assert
+class Object
+  def check: (untyped) -> (:int | :str)
+end

scenario/rbs/untyped-for-overload-tuple.rb

@@ -0,0 +1,17 @@
+## update: test.rbs
+class C
+  def foo: ([String, Integer]) -> :tuple
+         | (String) -> :str
+end
+
+## update: test.rb
+def check(unknown)
+  C.new.foo(unknown)
+end
+
+## diagnostics: test.rb
+
+## assert
+class Object
+  def check: (untyped) -> (:str | :tuple)
+end

scenario/rbs/untyped-for-overload.rb

@@ -11,5 +11,5 @@ def check
 
 ## assert
 class Object
-  def check: -> untyped
+  def check: -> (:A | :B)
 end