Fix ranking when multiple regions overlap

e.g.
  Match region #1: [-----------]
  Match region #2:       [---]
  Match region #3:         [------]

2 files changed, 51 insertions, 33 deletions

diff --git a/fzf b/fzf
index 4c69f1b0..bcdc0770 100755
--- a/fzf
+++ b/fzf
@@ -98,7 +98,7 @@ class FZF
       end
     while o = argv.shift
       case o
-      when '--version'           then version
+      when '--version'           then FZF.version
       when '-h', '--help'        then usage 0
       when '-m', '--multi'       then @multi    = true
       when '+m', '--no-multi'    then @multi    = false
@@ -225,7 +225,7 @@ class FZF
   def filter_list list
     matches = matcher.match(list, @filter, '', '')
     if @sort && matches.length <= @sort
-      matches = sort_by_rank(matches)
+      matches = FZF.sort(matches)
     end
     matches.each { |m| puts m.first }
   end
@@ -239,15 +239,34 @@ class FZF
       end
   end
 
-  def version
-    File.open(__FILE__, 'r') do |f|
-      f.each_line do |line|
-        if line =~ /Version: (.*)/
-          $stdout.puts 'fzf ' << $1
-          exit
+  class << self
+    def version
+      File.open(__FILE__, 'r') do |f|
+        f.each_line do |line|
+          if line =~ /Version: (.*)/
+            $stdout.puts 'fzf ' << $1
+            exit
+          end
         end
       end
     end
+
+    def sort list
+      list.sort_by { |tuple| rank tuple }
+    end
+
+    def rank tuple
+      line, offsets = tuple
+      matchlen = 0
+      pe = 0
+      offsets.sort.each do |pair|
+        b, e = pair
+        b    = pe if pe > b
+        pe   = e  if e > pe
+        matchlen += e - b if e > b
+      end
+      [matchlen, line.length, line]
+    end
   end
 
   def usage x, message = nil
@@ -519,21 +538,6 @@ class FZF
     C.attroff color(:chosen, true) if chosen
   end
 
-  def sort_by_rank list
-    list.sort_by { |tuple|
-      line, offsets = tuple
-      matchlen = 0
-      pe = nil
-      offsets.sort.each do |pair|
-        b, e = pair
-        b    = pe if pe && pe > b
-        pe   = e
-        matchlen += e - b
-      end
-      [matchlen, line.length, line]
-    }
-  end
-
   AFTER_1_9 = RUBY_VERSION.split('.').map { |e| e.rjust(3, '0') }.join >= '001009'
 
   if AFTER_1_9
@@ -725,7 +729,7 @@ class FZF
               next if skip
               matches = @sort ? found : found.reverse
               if !empty && @sort && matches.length <= @sort
-                matches = sort_by_rank(matches)
+                matches = FZF.sort(matches)
               end
               fcache[q] = matches
             end
diff --git a/test/test_fzf.rb b/test/test_fzf.rb
index ea2ecd96..fc30476d 100644
--- a/test/test_fzf.rb
+++ b/test/test_fzf.rb
@@ -400,7 +400,7 @@ class TestFZF < MiniTest::Unit::TestCase
        ["0____1",   [[0, 6]]],
        ["0_____1",  [[0, 7]]],
        ["0______1", [[0, 8]]]],
-      FZF.new([]).sort_by_rank(matcher.match(list, '01', '', '')))
+      FZF.sort(matcher.match(list, '01', '', '')))
 
     assert_equal(
       [["01",       [[0, 1], [1, 2]]],
@@ -411,16 +411,19 @@ class TestFZF < MiniTest::Unit::TestCase
        ["____0_1",  [[4, 5], [6, 7]]],
        ["0______1", [[0, 1], [7, 8]]],
        ["___01___", [[3, 4], [4, 5]]]],
-      FZF.new([]).sort_by_rank(xmatcher.match(list, '0 1', '', '')))
+      FZF.sort(xmatcher.match(list, '0 1', '', '')))
 
     assert_equal(
-      [["_01_",     [[1, 3], [0, 4]]],
-       ["0____1",   [[0, 6], [1, 3]]],
-       ["0_____1",  [[0, 7], [1, 3]]],
-       ["0______1", [[0, 8], [1, 3]]],
-       ["___01___", [[3, 5], [0, 2]]],
-       ["____0_1",  [[4, 7], [0, 2]]]],
-      FZF.new([]).sort_by_rank(xmatcher.match(list, '01 __', '', '')))
+      [["_01_",     [[1, 3], [0, 4]], [4, 4, "_01_"]],
+       ["___01___", [[3, 5], [0, 2]], [4, 8, "___01___"]],
+       ["____0_1",  [[4, 7], [0, 2]], [5, 7, "____0_1"]],
+       ["0____1",   [[0, 6], [1, 3]], [6, 6, "0____1"]],
+       ["0_____1",  [[0, 7], [1, 3]], [7, 7, "0_____1"]],
+       ["0______1", [[0, 8], [1, 3]], [8, 8, "0______1"]]],
+      FZF.sort(xmatcher.match(list, '01 __', '', '')).map { |tuple|
+         tuple << FZF.rank(tuple)
+       }
+    )
   end
 
   def test_extended_exact_mode
@@ -647,5 +650,16 @@ class TestFZF < MiniTest::Unit::TestCase
       $stdout = STDOUT
     end
   end
+
+  def test_ranking_overlap_match_regions
+    list = [
+      '1           3   4      2',
+      '1           2   3    4'
+    ]
+    assert_equal [
+      ['1           2   3    4',   [[0, 13], [16, 22]]],
+      ['1           3   4      2', [[0, 24], [12, 17]]],
+    ], FZF.sort(FZF::ExtendedFuzzyMatcher.new(nil).match(list, '12 34', '', ''))
+  end
 end