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diff --git a/spec/ruby/core/kernel/lambda_spec.rb b/spec/ruby/core/kernel/lambda_spec.rb
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+++ b/spec/ruby/core/kernel/lambda_spec.rb
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+require_relative '../../spec_helper'
+require_relative 'fixtures/classes'
+require_relative 'shared/lambda'
+
+# The functionality of lambdas is specified in core/proc
+
+describe "Kernel.lambda" do
+  it_behaves_like :kernel_lambda, :lambda
+
+  it "is a private method" do
+    Kernel.should have_private_instance_method(:lambda)
+  end
+
+  it "creates a lambda-style Proc if given a literal block" do
+    l = lambda { 42 }
+    l.lambda?.should be_true
+  end
+
+  it "creates a lambda-style Proc if given a literal block via #send" do
+    l = send(:lambda) { 42 }
+    l.lambda?.should be_true
+  end
+
+  it "creates a lambda-style Proc if given a literal block via #__send__" do
+    l = __send__(:lambda) { 42 }
+    l.lambda?.should be_true
+  end
+
+  ruby_version_is ""..."3.3" do
+    it "creates a lambda-style Proc if given a literal block via Kernel.public_send" do
+      suppress_warning do
+        l = Kernel.public_send(:lambda) { 42 }
+        l.lambda?.should be_true
+      end
+    end
+
+    it "returns the passed Proc if given an existing Proc" do
+      some_proc = proc {}
+      l = suppress_warning {lambda(&some_proc)}
+      l.should equal(some_proc)
+      l.lambda?.should be_false
+    end
+
+    it "creates a lambda-style Proc when called with zsuper" do
+      suppress_warning do
+        l = KernelSpecs::LambdaSpecs::ForwardBlockWithZSuper.new.lambda { 42 }
+        l.lambda?.should be_true
+        l.call.should == 42
+
+        lambda { l.call(:extra) }.should raise_error(ArgumentError)
+      end
+    end
+
+    it "returns the passed Proc if given an existing Proc through super" do
+      some_proc = proc { }
+      l = KernelSpecs::LambdaSpecs::SuperAmpersand.new.lambda(&some_proc)
+      l.should equal(some_proc)
+      l.lambda?.should be_false
+    end
+
+    it "does not create lambda-style Procs when captured with #method" do
+      kernel_lambda = method(:lambda)
+      l = suppress_warning {kernel_lambda.call { 42 }}
+      l.lambda?.should be_false
+      l.call(:extra).should == 42
+    end
+  end
+
+  it "checks the arity of the call when no args are specified" do
+    l = lambda { :called }
+    l.call.should == :called
+
+    lambda { l.call(1) }.should raise_error(ArgumentError)
+    lambda { l.call(1, 2) }.should raise_error(ArgumentError)
+  end
+
+  it "checks the arity when 1 arg is specified" do
+    l = lambda { |a| :called }
+    l.call(1).should == :called
+
+    lambda { l.call }.should raise_error(ArgumentError)
+    lambda { l.call(1, 2) }.should raise_error(ArgumentError)
+  end
+
+  it "does not check the arity when passing a Proc with &" do
+    l = lambda { || :called }
+    p = proc { || :called }
+
+    lambda { l.call(1) }.should raise_error(ArgumentError)
+    p.call(1).should == :called
+  end
+
+  it "accepts 0 arguments when used with ||" do
+    lambda {
+      lambda { || }.call(1)
+    }.should raise_error(ArgumentError)
+  end
+
+  it "strictly checks the arity when 0 or 2..inf args are specified" do
+    l = lambda { |a,b| }
+
+    lambda {
+      l.call
+    }.should raise_error(ArgumentError)
+
+    lambda {
+      l.call(1)
+    }.should raise_error(ArgumentError)
+
+    lambda {
+      l.call(1,2)
+    }.should_not raise_error(ArgumentError)
+  end
+
+  it "returns from the lambda itself, not the creation site of the lambda" do
+    @reached_end_of_method = nil
+    def test
+      send(:lambda) { return }.call
+      @reached_end_of_method = true
+    end
+    test
+    @reached_end_of_method.should be_true
+  end
+
+  it "allows long returns to flow through it" do
+    KernelSpecs::Lambda.new.outer.should == :good
+  end
+
+  it "treats the block as a Proc when lambda is re-defined" do
+    klass = Class.new do
+      def lambda (&block); block; end
+      def ret
+        lambda { return 1 }.call
+        2
+      end
+    end
+    klass.new.lambda { 42 }.should be_an_instance_of Proc
+    klass.new.ret.should == 1
+  end
+
+  context "when called without a literal block" do
+    ruby_version_is ""..."3.3" do
+      it "warns when proc isn't a lambda" do
+        -> { lambda(&proc{}) }.should complain("#{__FILE__}:#{__LINE__}: warning: lambda without a literal block is deprecated; use the proc without lambda instead\n")
+      end
+    end
+
+    ruby_version_is "3.3" do
+      it "raises when proc isn't a lambda" do
+        -> { lambda(&proc{}) }.should raise_error(ArgumentError, /the lambda method requires a literal block/)
+      end
+    end
+
+    it "doesn't warn when proc is lambda" do
+      -> { lambda(&lambda{}) }.should_not complain(verbose: true)
+    end
+  end
+end