Fix bug in truthy/falsy tests for booleans as objects

opal · Dec 6, 2013 · 1afbc44 · 1afbc44
1 parent 71c0f56
commit 1afbc44
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Showing 3 changed files with 29 additions and 2 deletions.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -27,6 +27,10 @@
     `!` as a def method name, and implements the method on `BasicObject`,
     `NilClass` and `Boolean`.
 
+*   Fixed bug where true/false as object literals from javascript were not
+    correctly being detected as truthy/falsy respectively. This is due to the
+    javascript "feature" where `new Boolean(false) !== false`.
+
 *   Moved `native.rb` to stdlib. Native support must now be explicitly required
     into Opal. `Native` is also now a module, instead of a top level class.
     Also added `Native::Object#respond_to?`.

diff --git a/lib/opal/nodes/helpers.rb b/lib/opal/nodes/helpers.rb
@@ -67,7 +67,7 @@ def js_truthy(sexp)
         end
 
         with_temp do |tmp|
-          [fragment("(#{tmp} = "), expr(sexp), fragment(") !== false && #{tmp} !== nil")]
+          [fragment("((#{tmp} = "), expr(sexp), fragment(") !== nil && (!#{tmp}._isBoolean || #{tmp} == true))")]
         end
       end
 
@@ -81,7 +81,7 @@ def js_falsy(sexp)
         end
 
         with_temp do |tmp|
-          [fragment("(#{tmp} = "), expr(sexp), fragment(") === false || #{tmp} === nil")]
+          [fragment("((#{tmp} = "), expr(sexp), fragment(") === nil || (#{tmp}._isBoolean && #{tmp} == false))")]
         end
       end
 

diff --git a/spec/opal/core/runtime/truthy_spec.rb b/spec/opal/core/runtime/truthy_spec.rb
@@ -0,0 +1,23 @@
+class Boolean
+  def self_as_an_object
+    self
+  end
+end
+
+describe "Opal truthyness" do
+  it "should evaluate to true using js `true` as an object" do
+    if true.self_as_an_object
+      called = true
+    end
+
+    called.should be_true
+  end
+
+  it "should evaluate to false using js `false` as an object" do
+    if false.self_as_an_object
+      called = true
+    end
+
+    called.should be_nil
+  end
+end