1 files changed, 38 insertions, 0 deletions
diff --git a/test/did_you_mean/tree_spell/test_change_word.rb b/test/did_you_mean/tree_spell/test_change_word.rb
new file mode 100644
index 0000000000..613e11b869
--- /dev/null
+++ b/test/did_you_mean/tree_spell/test_change_word.rb
@@ -0,0 +1,38 @@
+require_relative '../helper'
+require_relative 'change_word'
+
+class ChangeWordTest < Test::Unit::TestCase
+  def setup
+    @input = 'spec/services/anything_spec'
+    @cw = TreeSpell::ChangeWord.new(@input)
+    @len = @input.length
+  end
+
+  def test_deleletion
+    assert_match @cw.deletion(5), 'spec/ervices/anything_spec'
+    assert_match @cw.deletion(@len - 1), 'spec/services/anything_spe'
+    assert_match @cw.deletion(0), 'pec/services/anything_spec'
+  end
+
+  def test_substitution
+    assert_match @cw.substitution(5, '$'), 'spec/$ervices/anything_spec'
+    assert_match @cw.substitution(@len - 1, '$'), 'spec/services/anything_spe$'
+    assert_match @cw.substitution(0, '$'), '$pec/services/anything_spec'
+  end
+
+  def test_insertion
+    assert_match @cw.insertion(7, 'X'), 'spec/serXvices/anything_spec'
+    assert_match @cw.insertion(0, 'X'), 'Xspec/services/anything_spec'
+    assert_match @cw.insertion(@len - 1, 'X'), 'spec/services/anything_specX'
+  end
+
+  def test_transposition
+    n = @input.length
+    assert_match @cw.transposition(0, -1), 'psec/services/anything_spec'
+    assert_match @cw.transposition(n - 1, +1), 'spec/services/anything_spce'
+    assert_match @cw.transposition(4, +1), 'specs/ervices/anything_spec'
+    assert_match @cw.transposition(4, -1), 'spe/cservices/anything_spec'
+    assert_match @cw.transposition(21, -1), 'spec/services/anythign_spec'
+    assert_match @cw.transposition(21, +1), 'spec/services/anythin_gspec'
+  end
+end