String#split: skip nil groups. Fixes #3440

crystal-lang · Oct 19, 2016 · 2754433 · 2754433
1 parent 203da3a
commit 2754433
Showing 2 changed files with 4 additions and 1 deletion.
diff --git a/spec/std/string_spec.cr b/spec/std/string_spec.cr
@@ -716,6 +716,7 @@ describe "String" do
       assert { "a=".split(/\=/).should eq(["a", ""]) }
       assert { "=b".split(/\=/).should eq(["", "b"]) }
       assert { "=".split(/\=/, 2).should eq(["", ""]) }
+      assert { ",".split(/(?:(x)|(,))/).should eq(["", ",", ""]) }
 
       it "keeps groups" do
         s = "split on the word on okay?"

diff --git a/src/string.cr b/src/string.cr
@@ -2466,7 +2466,9 @@ class String
       count += 1
 
       1.upto(match.size) do |i|
-        ary.push match[i]
+        if group = match[i]?
+          ary.push group
+        end
       end
 
       last_slice_offset = slice_offset