diff options
Diffstat (limited to 'spec/ruby/core/io/ungetc_spec.rb')
-rw-r--r-- | spec/ruby/core/io/ungetc_spec.rb | 119 |
1 files changed, 119 insertions, 0 deletions
diff --git a/spec/ruby/core/io/ungetc_spec.rb b/spec/ruby/core/io/ungetc_spec.rb new file mode 100644 index 0000000000..ce4cc9d346 --- /dev/null +++ b/spec/ruby/core/io/ungetc_spec.rb @@ -0,0 +1,119 @@ +# -*- encoding: utf-8 -*- +require File.expand_path('../../../spec_helper', __FILE__) +require File.expand_path('../fixtures/classes', __FILE__) + +describe "IO#ungetc" do + before :each do + @io = IOSpecs.io_fixture "lines.txt" + + @empty = tmp('empty.txt') + end + + after :each do + @io.close unless @io.closed? + rm_r @empty + end + + it "pushes back one character onto stream" do + @io.getc.should == ?V + @io.ungetc(86) + @io.getc.should == ?V + + @io.ungetc(10) + @io.getc.should == ?\n + + @io.getc.should == ?o + @io.getc.should == ?i + # read the rest of line + @io.readline.should == "ci la ligne une.\n" + @io.getc.should == ?Q + @io.ungetc(99) + @io.getc.should == ?c + end + + it "pushes back one character when invoked at the end of the stream" do + # read entire content + @io.read + @io.ungetc(100) + @io.getc.should == ?d + end + + it "pushes back one character when invoked at the start of the stream" do + @io.read(0) + @io.ungetc(100) + @io.getc.should == ?d + end + + it "pushes back one character when invoked on empty stream" do + touch(@empty) + + File.open(@empty) { |empty| + empty.getc().should == nil + empty.ungetc(10) + empty.getc.should == ?\n + } + end + + it "affects EOF state" do + touch(@empty) + + File.open(@empty) { |empty| + empty.eof?.should == true + empty.getc.should == nil + empty.ungetc(100) + empty.eof?.should == false + } + end + + it "adjusts the stream position" do + @io.pos.should == 0 + + # read one char + c = @io.getc + @io.pos.should == 1 + @io.ungetc(c) + @io.pos.should == 0 + + # read all + @io.read + pos = @io.pos + @io.ungetc(98) + @io.pos.should == pos - 1 + end + + it "makes subsequent unbuffered operations to raise IOError" do + @io.getc + @io.ungetc(100) + lambda { @io.sysread(1) }.should raise_error(IOError) + end + + it "does not affect the stream and returns nil when passed nil" do + @io.getc.should == ?V + @io.ungetc(nil) + @io.getc.should == ?o + end + + it "puts one or more characters back in the stream" do + @io.gets + @io.ungetc("Aquí ").should be_nil + @io.gets.chomp.should == "Aquí Qui è la linea due." + end + + it "calls #to_str to convert the argument if it is not an Integer" do + chars = mock("io ungetc") + chars.should_receive(:to_str).and_return("Aquí ") + + @io.ungetc(chars).should be_nil + @io.gets.chomp.should == "Aquí Voici la ligne une." + end + + it "returns nil when invoked on stream that was not yet read" do + @io.ungetc(100).should be_nil + end + + it "raises IOError on closed stream" do + @io.getc + @io.close + lambda { @io.ungetc(100) }.should raise_error(IOError) + end +end |