Fix a line matching problem in Abbrev.abbrev(words, "prefix").

* lib/abbrev.rb (Abbrev#abbrev): A fixed string prefix pattern
  should only match the beginning of each word, not the beginning
  of every line in it.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@38027 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,9 @@
+Fri Nov 30 12:47:59 2012  Akinori MUSHA  <knu@iDaemons.org>
+
+	* lib/abbrev.rb (Abbrev#abbrev): A fixed string prefix pattern
+	  should only match the beginning of each word, not the beginning
+	  of every line in it.
+
 Fri Nov 30 12:30:55 2012  Akinori MUSHA  <knu@iDaemons.org>
 
 	* test/test_abbrev.rb: Add tests for lib/abbrev.rb.

lib/abbrev.rb

@@ -69,7 +69,7 @@ module Abbrev
     seen = Hash.new(0)
 
     if pattern.is_a?(String)
-      pattern = /^#{Regexp.quote(pattern)}/  # regard as a prefix
+      pattern = /\A#{Regexp.quote(pattern)}/  # regard as a prefix
     end
 
     words.each do |word|

test/test_abbrev.rb

@@ -36,12 +36,19 @@ class TestAbbrev < Test::Unit::TestCase
   end
 
   def test_abbrev_lf
+    words = ["abc", "abc\nd", "de"]
+
     assert_equal({
         "abc"     => "abc",
         "abc\n"   => "abc\nd",
         "abc\nd"  => "abc\nd",
         "d"       => "de",
         "de"      => "de",
-      }, Abbrev.abbrev(["abc", "abc\nd", "de"]))
+      }, words.abbrev)
+
+    assert_equal({
+        "d"       => "de",
+        "de"      => "de",
+      }, words.abbrev('d'))
   end
 end