3 files changed, 108 insertions, 0 deletions
diff --git a/spec/ruby/core/io/pread_spec.rb b/spec/ruby/core/io/pread_spec.rb
new file mode 100644
index 0000000000..b5b516fa53
--- /dev/null
+++ b/spec/ruby/core/io/pread_spec.rb
@@ -0,0 +1,52 @@
+# -*- encoding: utf-8 -*-
+require_relative '../../spec_helper'
+
+ruby_version_is "2.5" do
+  platform_is_not :windows do
+    describe "IO#pread" do
+      before :each do
+        @fname = tmp("io_pread.txt")
+        @contents = "1234567890"
+        touch(@fname) { |f| f.write @contents }
+        @file = File.open(@fname, "r+")
+      end
+
+      after :each do
+        @file.close
+        rm_r @fname
+      end
+
+      it "accepts a length, and an offset" do
+        @file.pread(4, 0).should == "1234"
+        @file.pread(3, 4).should == "567"
+      end
+
+      it "accepts a length, an offset, and an output buffer" do
+        buffer = "foo"
+        @file.pread(3, 4, buffer)
+        buffer.should == "567"
+      end
+
+      it "does not advance the file pointer" do
+        @file.pread(4, 0).should == "1234"
+        @file.read.should == "1234567890"
+      end
+
+      it "raises EOFError if end-of-file is reached" do
+        lambda { @file.pread(1, 10) }.should raise_error(EOFError)
+      end
+
+      it "raises IOError when file is not open in read mode" do
+        File.open(@fname, "w") do |file|
+          lambda { file.pread(1, 1) }.should raise_error(IOError)
+        end
+      end
+
+      it "raises IOError when file is closed" do
+        file = File.open(@fname, "r+")
+        file.close
+        lambda { file.pread(1, 1) }.should raise_error(IOError)
+      end
+    end
+  end
+end
diff --git a/spec/ruby/core/io/pwrite_spec.rb b/spec/ruby/core/io/pwrite_spec.rb
new file mode 100644
index 0000000000..fd3d1b98e9
--- /dev/null
+++ b/spec/ruby/core/io/pwrite_spec.rb
@@ -0,0 +1,45 @@
+# -*- encoding: utf-8 -*-
+require_relative '../../spec_helper'
+
+ruby_version_is "2.5" do
+  platform_is_not :windows do
+    describe "IO#pwrite" do
+      before :each do
+        @fname = tmp("io_pwrite.txt")
+        @file = File.open(@fname, "w+")
+      end
+
+      after :each do
+        @file.close
+        rm_r @fname
+      end
+
+      it "returns the number of bytes written" do
+        @file.pwrite("foo", 0).should == 3
+      end
+
+      it "accepts a string and an offset"  do
+        @file.pwrite("foo", 2)
+        @file.pread(3, 2).should == "foo"
+      end
+
+      it "does not advance the pointer in the file" do
+        @file.pwrite("bar", 3)
+        @file.write("foo")
+        @file.pread(6, 0).should == "foobar"
+      end
+
+      it "raises IOError when file is not open in write mode" do
+        File.open(@fname, "r") do |file|
+          lambda { file.pwrite("foo", 1) }.should raise_error(IOError)
+        end
+      end
+
+      it "raises IOError when file is closed" do
+        file = File.open(@fname, "w+")
+        file.close
+        lambda { file.pwrite("foo", 1) }.should raise_error(IOError)
+      end
+    end
+  end
+end
diff --git a/spec/ruby/core/io/write_spec.rb b/spec/ruby/core/io/write_spec.rb
index e6db3351db..50e3df864d 100644
--- a/spec/ruby/core/io/write_spec.rb
+++ b/spec/ruby/core/io/write_spec.rb
@@ -127,6 +127,17 @@ end
 
 describe "IO#write" do
   it_behaves_like :io_write, :write
+
+  ruby_version_is "2.5" do
+    it "accepts multiple arguments" do
+      IO.pipe do |r, w|
+        w.write("foo", "bar")
+        w.close
+
+        r.read.should == "foobar"
+      end
+    end
+  end
 end
 
 platform_is :windows do