1 files changed, 43 insertions, 0 deletions
diff --git a/spec/ruby/library/stringscanner/scan_spec.rb b/spec/ruby/library/stringscanner/scan_spec.rb
new file mode 100644
index 0000000000..84a0f27f08
--- /dev/null
+++ b/spec/ruby/library/stringscanner/scan_spec.rb
@@ -0,0 +1,43 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require 'strscan'
+
+describe "StringScanner#scan" do
+  before :each do
+    @s = StringScanner.new("This is a test")
+  end
+
+  it "returns the matched string" do
+    @s.scan(/\w+/).should == "This"
+    @s.scan(/.../).should == " is"
+    @s.scan(//).should == ""
+    @s.scan(/\s+/).should == " "
+  end
+
+  it "treats ^ as matching from the beginning of the current position" do
+    @s.scan(/\w+/).should == "This"
+    @s.scan(/^\d/).should be_nil
+    @s.scan(/^\s/).should == " "
+  end
+
+  it "returns nil if there's no match" do
+    @s.scan(/\d/).should == nil
+  end
+
+  it "returns nil when there is no more to scan" do
+    @s.scan(/[\w\s]+/).should == "This is a test"
+    @s.scan(/\w+/).should be_nil
+  end
+
+  it "returns an empty string when the pattern matches empty" do
+    @s.scan(/.*/).should == "This is a test"
+    @s.scan(/.*/).should == ""
+    @s.scan(/./).should be_nil
+  end
+
+  it "raises a TypeError if pattern isn't a Regexp" do
+    lambda { @s.scan("aoeu")    }.should raise_error(TypeError)
+    lambda { @s.scan(5)         }.should raise_error(TypeError)
+    lambda { @s.scan(:test)     }.should raise_error(TypeError)
+    lambda { @s.scan(mock('x')) }.should raise_error(TypeError)
+  end
+end