Improvements to `IO::Buffer` `read`/`write`/`pread`/`pwrite`. (#7826)

- Fix IO::Buffer `read`/`write` to use a minimum length.

1 files changed, 28 insertions, 7 deletions

diff --git a/test/ruby/test_io_buffer.rb b/test/ruby/test_io_buffer.rb
index b9d52d83ce..75ec4016fa 100644
--- a/test/ruby/test_io_buffer.rb
+++ b/test/ruby/test_io_buffer.rb
@@ -361,17 +361,38 @@ class TestIOBuffer < Test::Unit::TestCase
     input.close
   end
 
-  def test_read
+  def hello_world_tempfile
     io = Tempfile.new
     io.write("Hello World")
     io.seek(0)
 
-    buffer = IO::Buffer.new(128)
-    buffer.read(io, 5)
-
-    assert_equal "Hello", buffer.get_string(0, 5)
+    yield io
   ensure
-    io.close! if io
+    io&.close!
+  end
+
+  def test_read
+    hello_world_tempfile do |io|
+      buffer = IO::Buffer.new(128)
+      buffer.read(io)
+      assert_equal "Hello", buffer.get_string(0, 5)
+    end
+  end
+
+  def test_read_with_with_length
+    hello_world_tempfile do |io|
+      buffer = IO::Buffer.new(128)
+      buffer.read(io, 5)
+      assert_equal "Hello", buffer.get_string(0, 5)
+    end
+  end
+
+  def test_read_with_with_offset
+    hello_world_tempfile do |io|
+      buffer = IO::Buffer.new(128)
+      buffer.read(io, nil, 6)
+      assert_equal "Hello", buffer.get_string(6, 5)
+    end
   end
 
   def test_write
@@ -379,7 +400,7 @@ class TestIOBuffer < Test::Unit::TestCase
 
     buffer = IO::Buffer.new(128)
     buffer.set_string("Hello")
-    buffer.write(io, 5)
+    buffer.write(io)
 
     io.seek(0)
     assert_equal "Hello", io.read(5)