[GR-18163] Fix constant lookup in #instance_eval called with String

PullRequest: truffleruby/3592

CHANGELOG.md

@@ -20,6 +20,7 @@ Bug fixes:
 * Fix `Marshal.dump` when big Integer (that cannot be expressed with 4 bytes) is serialized (#2790, @andrykonchin).
 * Fix `Array#pack` and accept `Numeric` values when `Float` is expected (#2815, @andrykonchin).
 * Fix `\P{}` matching in regular expressions (#2798, @andrykonchin).
+* Fix constants lookup when `BasicObject#instance_eval` method is called with a String (#2810, @andrykonchin).
 
 Compatibility:
 

spec/ruby/core/basicobject/fixtures/classes.rb

@@ -15,8 +15,231 @@ module InstExecIncluded
     include InstExec
   end
 
-  module InstEvalCVar
-    instance_eval { @@count = 2 }
+  module InstEval
+    module CVar
+      module Get
+        class ReceiverScope
+          @@cvar = :value_defined_in_receiver_scope
+        end
+
+        class BlockDefinitionScope
+          @@cvar = :value_defined_in_block_definition_scope
+
+          def block
+            ->(*) { @@cvar }
+          end
+        end
+
+        class CallerScope
+          @@cvar = :value_defined_in_caller_scope
+
+          def get_class_variable_with_string(obj)
+            obj.instance_eval("@@cvar")
+          end
+
+          def get_class_variable_with_block(obj, block)
+            obj.instance_eval(&block)
+          end
+        end
+
+        class CallerWithoutCVarScope
+          def get_class_variable_with_string(obj)
+            obj.instance_eval("@@cvar")
+          end
+        end
+
+        ReceiverWithCVarDefinedInSingletonClass = Class.new.new.tap do |obj|
+          obj.singleton_class.class_variable_set(:@@cvar, :value_defined_in_receiver_singleton_class)
+        end
+      end
+
+      module Set
+        class ReceiverScope
+        end
+
+        class BlockDefinitionScope
+          def self.get_class_variable
+            @@cvar
+          end
+
+          def block_to_assign(value)
+            ->(*) { @@cvar = value }
+          end
+        end
+
+        class CallerScope
+          def self.get_class_variable
+            @@cvar
+          end
+
+          def set_class_variable_with_string(obj, value)
+            obj.instance_eval("@@cvar=#{value.inspect}")
+          end
+
+          def set_class_variable_with_block(obj, block)
+            obj.instance_eval(&block)
+          end
+        end
+      end
+    end
+  end
+
+  module InstEval
+    module Constants
+      module ConstantInReceiverSingletonClass
+        module ReceiverScope
+          FOO = :ReceiverScope
+
+          class ReceiverParent
+            FOO = :ReceiverParent
+          end
+
+          class Receiver < ReceiverParent
+            FOO = :Receiver
+
+            def initialize
+              self.singleton_class.const_set(:FOO, :singleton_class)
+            end
+          end
+        end
+
+        module CallerScope
+          FOO = :CallerScope
+
+          class CallerParent
+            FOO = :CallerParent
+          end
+
+          class Caller < CallerParent
+            FOO = :Caller
+
+            def get_constant_with_string(receiver)
+              receiver.instance_eval("FOO")
+            end
+          end
+        end
+      end
+
+      module ConstantInReceiverClass
+        module ReceiverScope
+          FOO = :ReceiverScope
+
+          class ReceiverParent
+            FOO = :ReceiverParent
+          end
+
+          class Receiver < ReceiverParent
+            FOO = :Receiver
+          end
+        end
+
+        module CallerScope
+          FOO = :CallerScope
+
+          class CallerParent
+            FOO = :CallerParent
+          end
+
+          class Caller < CallerParent
+            FOO = :Caller
+
+            def get_constant_with_string(receiver)
+              receiver.instance_eval("FOO")
+            end
+          end
+        end
+      end
+
+      module ConstantInCallerClass
+        module ReceiverScope
+          FOO = :ReceiverScope
+
+          class ReceiverParent
+            FOO = :ReceiverParent
+          end
+
+          class Receiver < ReceiverParent
+            # FOO is not declared in a receiver class
+          end
+        end
+
+        module CallerScope
+          FOO = :CallerScope
+
+          class CallerParent
+            FOO = :CallerParent
+          end
+
+          class Caller < CallerParent
+            FOO = :Caller
+
+            def get_constant_with_string(receiver)
+              receiver.instance_eval("FOO")
+            end
+          end
+        end
+      end
+
+      module ConstantInCallerOuterScopes
+        module ReceiverScope
+          FOO = :ReceiverScope
+
+          class ReceiverParent
+            FOO = :ReceiverParent
+          end
+
+          class Receiver < ReceiverParent
+            # FOO is not declared in a receiver class
+          end
+        end
+
+        module CallerScope
+          FOO = :CallerScope
+
+          class CallerParent
+            FOO = :CallerParent
+          end
+
+          class Caller < CallerParent
+            # FOO is not declared in a caller class
+
+            def get_constant_with_string(receiver)
+              receiver.instance_eval("FOO")
+            end
+          end
+        end
+      end
+
+      module ConstantInReceiverParentClass
+        module ReceiverScope
+          FOO = :ReceiverScope
+
+          class ReceiverParent
+            FOO = :ReceiverParent
+          end
+
+          class Receiver < ReceiverParent
+            # FOO is not declared in a receiver class
+          end
+        end
+
+        module CallerScope
+          # FOO is not declared in a caller outer scopes
+
+          class CallerParent
+            FOO = :CallerParent
+          end
+
+          class Caller < CallerParent
+            # FOO is not declared in a caller class
+
+            def get_constant_with_string(receiver)
+              receiver.instance_eval("FOO")
+            end
+          end
+        end
+      end
+    end
   end
 
   class InstEvalConst
@@ -26,7 +249,6 @@ class InstEvalConst
   module InstEvalOuter
     module Inner
       obj = InstEvalConst.new
-      X_BY_STR = obj.instance_eval("INST_EVAL_CONST_X") rescue nil
       X_BY_BLOCK = obj.instance_eval { INST_EVAL_CONST_X } rescue nil
     end
   end

spec/ruby/core/basicobject/instance_eval_spec.rb

@@ -89,6 +89,18 @@ def foo
     BasicObjectSpecs::IVars.new.instance_eval("@secret").should == 99
   end
 
+  it "raises TypeError for frozen objects when tries to set receiver's instance variables" do
+    -> { nil.instance_eval { @foo = 42 } }.should raise_error(FrozenError, "can't modify frozen NilClass: nil")
+    -> { true.instance_eval { @foo = 42 } }.should raise_error(FrozenError, "can't modify frozen TrueClass: true")
+    -> { false.instance_eval { @foo = 42 } }.should raise_error(FrozenError, "can't modify frozen FalseClass: false")
+    -> { 1.instance_eval { @foo = 42 } }.should raise_error(FrozenError, "can't modify frozen Integer: 1")
+    -> { :symbol.instance_eval { @foo = 42 } }.should raise_error(FrozenError, "can't modify frozen Symbol: :symbol")
+
+    obj = Object.new
+    obj.freeze
+    -> { obj.instance_eval { @foo = 42 } }.should raise_error(FrozenError)
+  end
+
   it "treats block-local variables as local to the block" do
     prc = instance_eval <<-CODE
       proc do |x, prc|
@@ -105,11 +117,6 @@ def foo
     prc.call(false, prc).should == 1
   end
 
-  it "sets class variables in the receiver" do
-    BasicObjectSpecs::InstEvalCVar.class_variables.should include(:@@count)
-    BasicObjectSpecs::InstEvalCVar.send(:class_variable_get, :@@count).should == 2
-  end
-
   it "makes the receiver metaclass the scoped class when used with a string" do
     obj = Object.new
     obj.instance_eval %{
@@ -119,8 +126,52 @@ class B; end
     obj.singleton_class.const_get(:B).should be_an_instance_of(Class)
   end
 
-  it "gets constants in the receiver if a string given" do
-    BasicObjectSpecs::InstEvalOuter::Inner::X_BY_STR.should == 2
+  describe "constants lookup when a String given" do
+    it "looks in the receiver singleton class first" do
+      receiver = BasicObjectSpecs::InstEval::Constants::ConstantInReceiverSingletonClass::ReceiverScope::Receiver.new
+      caller = BasicObjectSpecs::InstEval::Constants::ConstantInReceiverSingletonClass::CallerScope::Caller.new
+
+      caller.get_constant_with_string(receiver).should == :singleton_class
+    end
+
+    ruby_version_is ""..."3.1" do
+      it "looks in the caller scope next" do
+        receiver = BasicObjectSpecs::InstEval::Constants::ConstantInReceiverClass::ReceiverScope::Receiver.new
+        caller = BasicObjectSpecs::InstEval::Constants::ConstantInReceiverClass::CallerScope::Caller.new
+
+        caller.get_constant_with_string(receiver).should == :Caller
+      end
+    end
+
+    ruby_version_is "3.1" do
+      it "looks in the receiver class next" do
+        receiver = BasicObjectSpecs::InstEval::Constants::ConstantInReceiverClass::ReceiverScope::Receiver.new
+        caller = BasicObjectSpecs::InstEval::Constants::ConstantInReceiverClass::CallerScope::Caller.new
+
+        caller.get_constant_with_string(receiver).should == :Receiver
+      end
+    end
+
+    it "looks in the caller class next" do
+      receiver = BasicObjectSpecs::InstEval::Constants::ConstantInCallerClass::ReceiverScope::Receiver.new
+      caller = BasicObjectSpecs::InstEval::Constants::ConstantInCallerClass::CallerScope::Caller.new
+
+      caller.get_constant_with_string(receiver).should == :Caller
+    end
+
+    it "looks in the caller outer scopes next" do
+      receiver = BasicObjectSpecs::InstEval::Constants::ConstantInCallerOuterScopes::ReceiverScope::Receiver.new
+      caller = BasicObjectSpecs::InstEval::Constants::ConstantInCallerOuterScopes::CallerScope::Caller.new
+
+      caller.get_constant_with_string(receiver).should == :CallerScope
+    end
+
+    it "looks in the receiver class hierarchy next" do
+      receiver = BasicObjectSpecs::InstEval::Constants::ConstantInReceiverParentClass::ReceiverScope::Receiver.new
+      caller = BasicObjectSpecs::InstEval::Constants::ConstantInReceiverParentClass::CallerScope::Caller.new
+
+      caller.get_constant_with_string(receiver).should == :ReceiverParent
+    end
   end
 
   it "doesn't get constants in the receiver if a block given" do
@@ -136,17 +187,51 @@ class B; end
     end.should raise_error(TypeError)
   end
 
-quarantine! do # Not clean, leaves cvars lying around to break other specs
-  it "scopes class var accesses in the caller when called on an Integer" do
-    # Integer can take instance vars
-    Integer.class_eval "@@__tmp_instance_eval_spec = 1"
-    (defined? @@__tmp_instance_eval_spec).should be_nil
+  describe "class variables lookup" do
+    it "gets class variables in the caller class when called with a String" do
+      receiver = BasicObjectSpecs::InstEval::CVar::Get::ReceiverScope.new
+      caller = BasicObjectSpecs::InstEval::CVar::Get::CallerScope.new
+
+      caller.get_class_variable_with_string(receiver).should == :value_defined_in_caller_scope
+    end
+
+    it "gets class variables in the block definition scope when called with a block" do
+      receiver = BasicObjectSpecs::InstEval::CVar::Get::ReceiverScope.new
+      caller = BasicObjectSpecs::InstEval::CVar::Get::CallerScope.new
+      block = BasicObjectSpecs::InstEval::CVar::Get::BlockDefinitionScope.new.block
+
+      caller.get_class_variable_with_block(receiver, block).should == :value_defined_in_block_definition_scope
+    end
+
+    it "sets class variables in the caller class when called with a String" do
+      receiver = BasicObjectSpecs::InstEval::CVar::Set::ReceiverScope.new
+      caller = BasicObjectSpecs::InstEval::CVar::Set::CallerScope.new
+
+      caller.set_class_variable_with_string(receiver, 1)
+      BasicObjectSpecs::InstEval::CVar::Set::CallerScope.get_class_variable.should == 1
+    end
+
+    it "sets class variables in the block definition scope when called with a block" do
+      receiver = BasicObjectSpecs::InstEval::CVar::Set::ReceiverScope.new
+      caller = BasicObjectSpecs::InstEval::CVar::Set::CallerScope.new
+      block = BasicObjectSpecs::InstEval::CVar::Set::BlockDefinitionScope.new.block_to_assign(1)
+
+      caller.set_class_variable_with_block(receiver, block)
+      BasicObjectSpecs::InstEval::CVar::Set::BlockDefinitionScope.get_class_variable.should == 1
+    end
+
+    it "does not have access to class variables in the receiver class when called with a String" do
+      receiver = BasicObjectSpecs::InstEval::CVar::Get::ReceiverScope.new
+      caller = BasicObjectSpecs::InstEval::CVar::Get::CallerWithoutCVarScope.new
+      -> { caller.get_class_variable_with_string(receiver) }.should raise_error(NameError, /uninitialized class variable @@cvar/)
+    end
 
-    @@__tmp_instance_eval_spec = 2
-    1.instance_eval { @@__tmp_instance_eval_spec }.should == 2
-    Integer.__send__(:remove_class_variable, :@@__tmp_instance_eval_spec)
+    it "does not have access to class variables in the receiver's singleton class when called with a String" do
+      receiver = BasicObjectSpecs::InstEval::CVar::Get::ReceiverWithCVarDefinedInSingletonClass
+      caller = BasicObjectSpecs::InstEval::CVar::Get::CallerWithoutCVarScope.new
+      -> { caller.get_class_variable_with_string(receiver) }.should raise_error(NameError, /uninitialized class variable @@cvar/)
+    end
   end
-end
 
   it "raises a TypeError when defining methods on numerics" do
     -> do