Uncache previously-used Java type when assigning a bare value.

Fixes #4178.
jruby · Sep 27, 2016 · 8347545 · 8347545
1 parent 21b9760
commit 8347545
Show file tree

Hide file tree

Showing 2 changed files with 11 additions and 4 deletions.
diff --git a/core/src/main/java/org/jruby/embed/variable/AbstractVariable.java b/core/src/main/java/org/jruby/embed/variable/AbstractVariable.java
@@ -102,7 +102,8 @@ protected void updateByJavaObject(final Ruby runtime, Object... values) {
         } else if (values.length > 1) {
             javaType = (Class) values[1];
         } else {
-            javaType = javaObject.getClass();
+            // When a new object comes in without a target type, clear out cached type
+            javaType = null;
         }
         irubyObject = JavaEmbedUtils.javaToRuby(runtime, javaObject);
         fromRuby = false;
@@ -141,9 +142,6 @@ public Object getJavaObject() {
         }
         else { // Ruby originated variables
             javaObject = irubyObject.toJava(Object.class);
-            if (javaObject != null) {
-                javaType = javaObject.getClass();
-            }
         }
         return javaObject;
     }

diff --git a/spec/regression/GH-4178_script_engine_should_not_cache_variable_coercion_type_spec.rb b/spec/regression/GH-4178_script_engine_should_not_cache_variable_coercion_type_spec.rb
@@ -0,0 +1,9 @@
+describe "java.script.ScriptManager for JRuby" do
+  describe "when assigning global variables" do
+    it "allows different types of values to be assigned in sequence" do
+      engine = javax.script.ScriptEngineManager.new.getEngineByName("jruby")
+      expect(engine.eval("$x = 10")).to eq 10
+      expect(engine.eval("$x = 'a'")).to eq 'a'
+    end
+  end
+end