fix: do not close nested types too early

Closes #775.
teal-language · Aug 13, 2024 · e178c42 · e178c42
1 parent 07c9ed4
commit e178c42
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Showing 3 changed files with 74 additions and 20 deletions.
diff --git a/spec/declaration/record_function_spec.lua b/spec/declaration/record_function_spec.lua
@@ -107,5 +107,25 @@ describe("record function", function()
       ]], {}, {
          { y = 7, msg = "different number of return values: got 1, expected 0" },
       }))
+
+      it("does not close nested types too early (regression test for #775)", util.check([[
+         -- declare a nested record
+         local record mul
+            record Fil
+               mime: function(Fil)
+            end
+         end
+
+         -- declare an alias
+         local type Fil = mul.Fil
+
+         -- this works
+         function mul.Fil:new_method1(self: Fil)
+         end
+
+         -- should work as well for alias
+         function Fil:new_method2(self: Fil)
+         end
+      ]]))
    end)
 end)
diff --git a/tl.lua b/tl.lua
@@ -12277,22 +12277,38 @@ self:expand_type(node, values, elements) })
       end,
    }
 
+   function TypeChecker:begin_temporary_record_types(typ)
+      self:add_var(nil, "@self", type_at(typ, a_type(typ, "typedecl", { def = typ })))
+
+      for fname, ftype in fields_of(typ) do
+         if ftype.typename == "typealias" then
+            self:resolve_nominal(ftype.alias_to)
+            self:add_var(nil, fname, ftype)
+         elseif ftype.typename == "typedecl" then
+            self:add_var(nil, fname, ftype)
+         end
+      end
+   end
+
+   function TypeChecker:end_temporary_record_types(typ)
+
+
+      local scope = self.st[#self.st]
+      scope.vars["@self"] = nil
+      for fname, ftype in fields_of(typ) do
+         if ftype.typename == "typealias" or ftype.typename == "typedecl" then
+            scope.vars[fname] = nil
+         end
+      end
+   end
+
    local visit_type
    visit_type = {
       cbs = {
          ["record"] = {
             before = function(self, typ)
                self:begin_scope()
-               self:add_var(nil, "@self", type_at(typ, a_type(typ, "typedecl", { def = typ })))
-
-               for fname, ftype in fields_of(typ) do
-                  if ftype.typename == "typealias" then
-                     self:resolve_nominal(ftype.alias_to)
-                     self:add_var(nil, fname, ftype)
-                  elseif ftype.typename == "typedecl" then
-                     self:add_var(nil, fname, ftype)
-                  end
-               end
+               self:begin_temporary_record_types(typ)
             end,
             after = function(self, typ, children)
                local i = 1
@@ -12386,6 +12402,7 @@ self:expand_type(node, values, elements) })
                   end
                end
 
+               self:end_temporary_record_types(typ)
                self:end_scope()
 
                return typ

diff --git a/tl.tl b/tl.tl
@@ -12277,22 +12277,38 @@ do
       end,
    }
 
+   function TypeChecker:begin_temporary_record_types(typ: RecordType)
+      self:add_var(nil, "@self", type_at(typ, a_typedecl(typ, typ)))
+
+      for fname, ftype in fields_of(typ) do
+         if ftype is TypeAliasType then
+            self:resolve_nominal(ftype.alias_to)
+            self:add_var(nil, fname, ftype)
+         elseif ftype is TypeDeclType then
+            self:add_var(nil, fname, ftype)
+         end
+      end
+   end
+
+   function TypeChecker:end_temporary_record_types(typ: RecordType)
+      -- drop @self and nested records from scope
+      -- to avoid closing them prematurely in end_scope()
+      local scope = self.st[#self.st]
+      scope.vars["@self"] = nil
+      for fname, ftype in fields_of(typ) do
+         if ftype is TypeAliasType or ftype is TypeDeclType then
+            scope.vars[fname] = nil
+         end
+      end
+   end
+
    local visit_type: Visitor<TypeChecker, TypeName,Type,Type>
    visit_type = {
       cbs = {
          ["record"] = {
             before = function(self: TypeChecker, typ: RecordType)
                self:begin_scope()
-               self:add_var(nil, "@self", type_at(typ, a_typedecl(typ, typ)))
-
-               for fname, ftype in fields_of(typ) do
-                  if ftype is TypeAliasType then
-                     self:resolve_nominal(ftype.alias_to)
-                     self:add_var(nil, fname, ftype)
-                  elseif ftype is TypeDeclType then
-                     self:add_var(nil, fname, ftype)
-                  end
-               end
+               self:begin_temporary_record_types(typ)
             end,
             after = function(self: TypeChecker, typ: RecordType, children: {Type}): Type
                local i = 1
@@ -12386,6 +12402,7 @@ do
                   end
                end
 
+               self:end_temporary_record_types(typ)
                self:end_scope()
 
                return typ