Major investigation to Diff::LCS bugs.

- Fixed some formatting and style issues.
  - Trailing spaces
  - Calling class methods using '.' instead of '::'.
- Resolved Issue #2 by handling string[string.size, 1] properly (it
  returns "" not nil).
- Added special case handling for Diff::LCS.patch so that it handles
  patches that are empty or contain no changes.
- Adding temporary code to help determined the reason for the
  misidentification of patch direction.
- Added a number of different specs to check for comparing the same
  value.
- Added broken spec filtering.

1 files changed, 23 insertions, 0 deletions

diff --git a/spec/issues_spec.rb b/spec/issues_spec.rb
new file mode 100644
index 0000000..32a81e6
--- /dev/null
+++ b/spec/issues_spec.rb
@@ -0,0 +1,23 @@
+# -*- ruby encoding: utf-8 -*-
+
+require 'spec_helper'
+
+describe "Diff::LCS Issues" do
+  include Diff::LCS::SpecHelper::Matchers
+
+  it "should not fail to provide a simple patchset (issue 1)", :broken => true do
+    s1, s2 = *%W(aX bXaX)
+    correct_forward_diff = [
+      [ [ '+', 0, 'b' ],
+        [ '+', 1, 'X' ] ],
+    ]
+
+    diff_s1_s2 = Diff::LCS.diff(s1, s2)
+    change_diff(correct_forward_diff).should == diff_s1_s2
+    expect do
+      Diff::LCS.patch(s1, diff_s1_s2).should == s2
+    end.to_not raise_error(RuntimeError, /provided patchset/)
+  end
+end
+
+# vim: ft=ruby