[Truffle] Implement Binding#local_variable_defined?

jruby · Sep 1, 2016 · 772f381 · 772f381
1 parent 3cf0b5b
commit 772f381
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Showing 2 changed files with 32 additions and 5 deletions.
diff --git a/spec/truffle/tags/core/binding/local_variable_defined_tags.txt b/spec/truffle/tags/core/binding/local_variable_defined_tags.txt
@@ -1,7 +1,2 @@
-fails:Binding#local_variable_defined? returns false when a variable is not defined
-fails:Binding#local_variable_defined? returns true when a regular local variable is defined
-fails:Binding#local_variable_defined? returns true when a local variable is defined using eval()
-fails:Binding#local_variable_defined? returns true when a local variable is defined using Binding#local_variable_set
-fails:Binding#local_variable_defined? returns true when a local variable is defined in a parent scope
 fails:Binding#local_variable_defined? allows usage of a String as the variable name
 fails:Binding#local_variable_defined? allows usage of an object responding to #to_str as the variable name
diff --git a/truffle/src/main/java/org/jruby/truffle/core/binding/BindingNodes.java b/truffle/src/main/java/org/jruby/truffle/core/binding/BindingNodes.java
@@ -130,6 +130,38 @@ private MaterializedFrame copyFrame(MaterializedFrame frame) {
 
     }
 
+    @ImportStatic(BindingNodes.class)
+    @CoreMethod(names = "local_variable_defined?", required = 1)
+    public abstract static class LocalVariableDefinedNode extends CoreMethodArrayArgumentsNode {
+
+        private final DynamicObject dollarUnderscore;
+
+        public LocalVariableDefinedNode(RubyContext context, SourceSection sourceSection) {
+            super(context, sourceSection);
+            dollarUnderscore = getSymbol("$_");
+        }
+
+        @TruffleBoundary
+        @Specialization(guards = {"isRubySymbol(symbol)", "!isLastLine(symbol)"})
+        public boolean localVariableDefinedUncached(DynamicObject binding, DynamicObject symbol) {
+            final FrameSlotAndDepth frameSlot = findFrameSlotOrNull(binding, symbol);
+            return frameSlot != null;
+        }
+
+        @TruffleBoundary
+        @Specialization(guards = {"isRubySymbol(symbol)", "isLastLine(symbol)"})
+        public Object localVariableDefinedLastLine(DynamicObject binding, DynamicObject symbol) {
+            final MaterializedFrame frame = Layouts.BINDING.getFrame(binding);
+            final FrameSlot frameSlot = frame.getFrameDescriptor().findFrameSlot(Layouts.SYMBOL.getString(symbol));
+            return frameSlot != null;
+        }
+
+        protected boolean isLastLine(DynamicObject symbol) {
+            return symbol == dollarUnderscore;
+        }
+
+    }
+
     @ImportStatic(BindingNodes.class)
     @CoreMethod(names = "local_variable_get", required = 1)
     public abstract static class LocalVariableGetNode extends CoreMethodArrayArgumentsNode {