ruby: provide informative exception for trailing escapes in tables

CHANGELOG.md

@@ -8,6 +8,7 @@ This document is formatted according to the principles of [Keep A CHANGELOG](htt
 
 ## [Unreleased]
 ### Fixed
+- [Ruby] Provide informative exception for trailing escapes in tables ([#244](https://github.com/cucumber/gherkin/pull/244))
 - [Python] Provide informative exception for trailing escapes in tables ([#241](https://github.com/cucumber/gherkin/pull/241))
 - (i18n) Provide trailing space in Irish step keywords ([#243](https://github.com/cucumber/gherkin/pull/243))
 - (i18n) Provide trailing space in Korean step keywords ([#254](https://github.com/cucumber/gherkin/pull/254))

ruby/lib/gherkin/gherkin_line.rb

@@ -66,7 +66,7 @@ def split_table_cells(row)
           cell = ''
           start_col = col + 1
         elsif char == '\\'
-          char = row[col]
+          char = row[col] || ''
           col += 1
           if char == 'n'
             cell += "\n"

ruby/spec/gherkin/gherkin_line_spec.rb

@@ -32,5 +32,9 @@ def cells_text(line)
     it 'does not drop white spaces inside a cell' do
       expect(cells_text("| foo()\n  bar\nbaz |")).to eq(["foo()\n  bar\nbaz"])
     end
+
+    it 'trailing escapes are ignored' do
+      expect(cells_text("| a |\\")).to eq(['a'])
+    end
   end
 end