Add spec for IO::Buffer#initialize

Author: trinistr

core/io/buffer/initialize_spec.rb

@@ -0,0 +1,105 @@
+require_relative '../../../spec_helper'
+
+describe "IO::Buffer#initialize" do
+ after :each do
+ @buffer&.free
+ end
+
+ it "creates a new zero-filled buffer with default size" do
+ @buffer = IO::Buffer.new
+ @buffer.size.should == IO::Buffer::DEFAULT_SIZE
+ @buffer.each(:U8).should.all? { |_offset, value| value.eql?(0) }
+ end
+
+ it "creates a buffer with default state" do
+ @buffer = IO::Buffer.new
+ @buffer.should_not.shared?
+ @buffer.should_not.readonly?
+
+ @buffer.should_not.empty?
+ @buffer.should_not.null?
+
+ # This is run-time state, set by #locked.
+ @buffer.should_not.locked?
+ end
+
+ context "with size argument" do
+ it "creates a new internal buffer if size is less than IO::Buffer::PAGE_SIZE" do
+ size = IO::Buffer::PAGE_SIZE - 1
+ @buffer = IO::Buffer.new(size)
+ @buffer.size.should == size
+ @buffer.should.internal?
+ @buffer.should_not.empty?
+ end
+
+ it "creates a new mapped buffer if size is greater than or equal to IO::Buffer::PAGE_SIZE" do
+ size = IO::Buffer::PAGE_SIZE
+ @buffer = IO::Buffer.new(size)
+ @buffer.size.should == size
+ @buffer.should.mapped?
+ @buffer.should_not.empty?
+ end
+
+ it "creates a null buffer if size is 0" do
+ @buffer = IO::Buffer.new(0)
+ @buffer.size.should.zero?
+ @buffer.should.null?
+ @buffer.should.empty?
+ end
+
+ it "raises TypeError if size is not an Integer" do
+ -> { IO::Buffer.new(nil) }.should raise_error(TypeError, "not an Integer")
+ -> { IO::Buffer.new(10.0) }.should raise_error(TypeError, "not an Integer")
+ end
+
+ it "raises ArgumentError if size is negative" do
+ -> { IO::Buffer.new(-1) }.should raise_error(ArgumentError, "Size can't be negative!")
+ end
+ end
+
+ context "with size and flags arguments" do
+ it "forces mapped buffer with IO::Buffer::MAPPED flag" do
+ @buffer = IO::Buffer.new(IO::Buffer::PAGE_SIZE - 1, IO::Buffer::MAPPED)
+ @buffer.should.mapped?
+ @buffer.should_not.internal?
+ @buffer.should_not.empty?
+ end
+
+ it "forces internal buffer with IO::Buffer::INTERNAL flag" do
+ @buffer = IO::Buffer.new(IO::Buffer::PAGE_SIZE, IO::Buffer::INTERNAL)
+ @buffer.should.internal?
+ @buffer.should_not.mapped?
+ @buffer.should_not.empty?
+ end
+
+ # This looks like a bug to me, these should be different memory models?
+ # Definitely looks like a bug, created issue: https://bugs.ruby-lang.org/issues/21672
+ it "creates internal-mapped buffer if INTERNAL and MAPPED are both specified" do
+ @buffer = IO::Buffer.new(10, IO::Buffer::INTERNAL | IO::Buffer::MAPPED)
+ @buffer.should.internal?
+ @buffer.should.mapped?
+ @buffer.should_not.empty?
+ end
+
+ it "raises ArgumentError if flags is negative" do
+ -> { IO::Buffer.new(10, -1) }.should raise_error(ArgumentError, "Flags can't be negative!")
+ end
+
+ it "raises IO::Buffer::AllocationError with other values for flags" do
+ -> { IO::Buffer.new(10, IO::Buffer::READONLY) }.should raise_error(IO::Buffer::AllocationError, "Could not allocate buffer!")
+ -> { IO::Buffer.new(10, 0) }.should raise_error(IO::Buffer::AllocationError, "Could not allocate buffer!")
+ end
+
+ ruby_version_is ""..."3.3" do
+ it "raises IO::Buffer::AllocationError with non-Integer flags" do
+ -> { IO::Buffer.new(10, 0.0) }.should raise_error(IO::Buffer::AllocationError, "Could not allocate buffer!")
+ end
+ end
+
+ ruby_version_is "3.3" do
+ it "raises TypeError with non-Integer flags" do
+ -> { IO::Buffer.new(10, 0.0) }.should raise_error(TypeError, "not an Integer")
+ end
+ end
+ end
+end