1 files changed, 63 insertions, 10 deletions
diff --git a/spec/ruby/core/kernel/caller_spec.rb b/spec/ruby/core/kernel/caller_spec.rb
index c3d63ccb00..225f6fc458 100644
--- a/spec/ruby/core/kernel/caller_spec.rb
+++ b/spec/ruby/core/kernel/caller_spec.rb
@@ -3,7 +3,7 @@ require_relative 'fixtures/caller'
 
 describe 'Kernel#caller' do
   it 'is a private method' do
-    Kernel.should have_private_instance_method(:caller)
+    Kernel.private_instance_methods(false).should.include?(:caller)
   end
 
   it 'returns an Array of caller locations' do
@@ -32,7 +32,7 @@ describe 'Kernel#caller' do
     locations = KernelSpecs::CallerTest.locations
     line      = __LINE__ - 1
 
-    locations[0].should include("#{__FILE__}:#{line}:in")
+    locations[0].should.include?("#{__FILE__}:#{line}:in")
   end
 
   it "returns an Array with the block given to #at_exit at the base of the stack" do
@@ -43,26 +43,79 @@ describe 'Kernel#caller' do
     lines[1].should =~ /\A#{path}:2:in [`']block in <main>'\n\z/
   end
 
+  it "can be called with a range" do
+    locations1 = caller(0)
+    locations2 = caller(2..4)
+    locations1[2..4].should == locations2
+  end
+
   it "works with endless ranges" do
     locations1 = KernelSpecs::CallerTest.locations(0)
     locations2 = KernelSpecs::CallerTest.locations(eval("(2..)"))
-    locations2.map(&:to_s).should == locations1[2..-1].map(&:to_s)
+    locations2.should == locations1[2..-1]
   end
 
   it "works with beginless ranges" do
     locations1 = KernelSpecs::CallerTest.locations(0)
     locations2 = KernelSpecs::CallerTest.locations((..5))
-    locations2.map(&:to_s)[eval("(2..)")].should == locations1[(..5)].map(&:to_s)[eval("(2..)")]
+    locations2[eval("(2..)")].should == locations1[(..5)][eval("(2..)")]
+  end
+
+  it "can be called with a range whose end is negative" do
+    locations1 = caller(0)
+    locations2 = caller(2..-1)
+    locations3 = caller(2..-2)
+    locations1[2..-1].should == locations2
+    locations1[2..-2].should == locations3
+  end
+
+  it "must return nil if omitting more locations than available" do
+    caller(100).should == nil
+    caller(100..-1).should == nil
+  end
+
+  it "must return [] if omitting exactly the number of locations available" do
+    omit = caller(0).length
+    caller(omit).should == []
+  end
+
+  it "must return the same locations when called with 1..-1 and when called with no arguments" do
+    caller.should == caller(1..-1)
   end
 
   guard -> { Kernel.instance_method(:tap).source_location } do
-    it "includes core library methods defined in Ruby" do
-      file, line = Kernel.instance_method(:tap).source_location
-      file.should.start_with?('<internal:')
+    ruby_version_is ""..."3.4" do
+      it "includes core library methods defined in Ruby" do
+        file, line = Kernel.instance_method(:tap).source_location
+        file.should.start_with?('<internal:')
+
+        loc = nil
+        tap { loc = caller(1, 1)[0] }
+        loc.should =~ /\A<internal:.*in `tap'\z/
+      end
+    end
+
+    ruby_version_is "3.4"..."4.0" do
+      it "includes core library methods defined in Ruby" do
+        file, line = Kernel.instance_method(:tap).source_location
+        file.should.start_with?('<internal:')
+
+        loc = nil
+        tap { loc = caller(1, 1)[0] }
+        loc.should =~ /\A<internal:.*in 'Kernel#tap'\z/
+      end
+    end
+
+    ruby_version_is "4.0" do
+      it "does not include core library methods defined in Ruby" do
+        file, line = Kernel.instance_method(:tap).source_location
+        file.should.start_with?('<internal:')
 
-      loc = nil
-      tap { loc = caller(1, 1)[0] }
-      loc.should =~ /\A<internal:.*in [`'](?:Kernel#)?tap'\z/
+        loc = nil
+        tap { loc = caller(1, 1)[0] }
+        # CRuby hides the file which defines the method: https://bugs.ruby-lang.org/issues/20968
+        loc.should =~ /\A(<internal:|#{__FILE__}:).*in 'Kernel#tap'\z/
+      end
     end
   end
 end