Properly replace packed 2-tuple entries with those coming in.

headius · enebo · commit 2e1327fdbd31 · 2016-09-01T15:08:58.000-05:00
Fixes jruby#4124.
diff --git a/core/src/main/java/org/jruby/specialized/RubyArrayTwoObject.java b/core/src/main/java/org/jruby/specialized/RubyArrayTwoObject.java
@@ -252,7 +252,7 @@ public IRubyObject replace(IRubyObject orig) {
 
         if (origArr.size() == 2) {
             car = origArr.eltInternal(0);
-            cdr = origArr.eltInternal(0);
+            cdr = origArr.eltInternal(1);
             return this;
         }
 
diff --git a/spec/regression/GH-4124_packed_array_replace_spec.rb b/spec/regression/GH-4124_packed_array_replace_spec.rb
@@ -0,0 +1,13 @@
+describe '#4124 Packed arrays' do
+  it 'replaces properly' do
+    # try a range of sizes, since we may expand packed arrays
+    arys = 1.upto(10).map {|i| (1..i).to_a }
+
+    arys.each do |ary|
+      plus_one = ary.map {|i| i+1}
+      ary.replace plus_one
+
+      ary.should == plus_one
+    end
+  end
+end

Original file line number	Diff line number	Diff line change
`@@ -252,7 +252,7 @@ public IRubyObject replace(IRubyObject orig) {`
`252`	`252`
`253`	`253`	`if (origArr.size() == 2) {`
`254`	`254`	`car = origArr.eltInternal(0);`
`255`		`- cdr = origArr.eltInternal(0);`
	`255`	`+ cdr = origArr.eltInternal(1);`
`256`	`256`	`return this;`
`257`	`257`	`}`
`258`	`258`