Merge pull request #77 from judofyr/clarify-call

Improved documentation/tests for exec/eval/call

Author: rafaelfranca

lib/execjs/duktape_runtime.rb

@@ -26,7 +26,8 @@ def eval(source, options = {})
       end
 
       def call(identifier, *args)
-        @ctx.call_prop(identifier.split("."), *args)
+        @ctx.exec_string("__execjs_duktape_call = #{identifier}", '(execjs)')
+        @ctx.call_prop("__execjs_duktape_call", *args)
       rescue Exception => e
         raise wrap_error(e)
       end

lib/execjs/ruby_racer_runtime.rb

@@ -42,7 +42,7 @@ def eval(source, options = {})
       def call(properties, *args)
         lock do
           begin
-            unbox @v8_context.eval(properties).call(*args)
+            unbox @v8_context.eval("(#{properties})").call(*args)
           rescue ::V8::JSError => e
             raise wrap_error(e)
           end

lib/execjs/runtime.rb

@@ -9,15 +9,30 @@ class Context
       def initialize(runtime, source = "", options = {})
       end
 
+      # Evaluates the +source+ in the context of a function body and returns the
+      # returned value.
+      #
+      #   context.exec("return 1") # => 1
+      #   context.exec("1")        # => nil (nothing was returned)
       def exec(source, options = {})
         raise NotImplementedError
       end
 
+      # Evaluates the +source+ as an expression and returns the result.
+      #
+      #   context.eval("1")        # => 1
+      #   context.eval("return 1") # => Raises SyntaxError
       def eval(source, options = {})
         raise NotImplementedError
       end
 
-      def call(properties, *args)
+      # Evaluates +source+ as an expression (which should be of type
+      # +function+), and calls the function with the given arguments.
+      # The function will be evaluated with the global object as +this+.
+      #
+      #   context.call("function(a, b) { return a + b }", 1, 1) # => 2
+      #   context.call("CoffeeScript.compile", "1 + 1")
+      def call(source, *args)
         raise NotImplementedError
       end
     end

test/test_execjs.rb

@@ -48,6 +48,34 @@ def test_nested_context_call
     assert_equal "bar", context.call("a.b.id", "bar")
   end
 
+  def test_call_with_complex_properties
+    context = ExecJS.compile("")
+    assert_equal 2, context.call("function(a, b) { return a + b }", 1, 1)
+
+    context = ExecJS.compile("foo = 1")
+    assert_equal 2, context.call("(function(bar) { return foo + bar })", 1)
+  end
+
+  def test_call_with_this
+    # Known bug: https://github.com/cowboyd/therubyrhino/issues/39
+    skip if ExecJS.runtime.is_a?(ExecJS::RubyRhinoRuntime)
+
+    # Make sure that `this` is indeed the global scope
+    context = ExecJS.compile(<<-EOF)
+      name = 123;
+
+      function Person(name) {
+        this.name = name;
+      }
+
+      Person.prototype.getThis = function() {
+        return this.name;
+      }
+    EOF
+
+    assert_equal 123, context.call("(new Person('Bob')).getThis")
+  end
+
   def test_context_call_missing_function
     context = ExecJS.compile("")
     assert_raises ExecJS::ProgramError do