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catmandocatmando
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closes #152 
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3 files changed

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3 files changed

+104
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‎lib/react/component/class_methods.rb

Lines changed: 5 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -2,6 +2,11 @@ module React
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module Component
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# class level methods (macros) for components
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module ClassMethods
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def reactrb_component?
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true
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end
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def backtrace(*args)
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@dont_catch_exceptions = (args[0] == :none)
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@backtrace_off = @dont_catch_exceptions || (args[0] == :off)

‎lib/react/rendering_context.rb

Lines changed: 47 additions & 15 deletions
Original file line numberDiff line numberDiff line change
@@ -13,24 +13,12 @@ def self.build_only(name, *args, &block)
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def self.render(name, *args, &block)
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remove_nodes_from_args(args)
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@buffer = [] unless @buffer
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@buffer ||= [] unless @buffer
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if block
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element = build do
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saved_waiting_on_resources = waiting_on_resources
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self.waiting_on_resources = nil
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result = block.call
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# Todo figure out how children rendering should happen, probably should have special method that pushes children into the buffer
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# i.e. render_child/render_children that takes Element/Array[Element] and does the push into the buffer
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if !name && ( # !name means called from outer render so we check that it has rendered correctly
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(@buffer.count > 1) || # should only render one element
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(@buffer.count == 1 && @buffer.last != result) || # it should return that element
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(@buffer.count == 0 && !(result.is_a?(String) || (result.respond_to?(:acts_as_string?) && result.acts_as_string?) || result.is_a?(Element))) #for convience we will also convert the return value to a span if its a string
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)
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raise "a components render method must generate and return exactly 1 element or a string"
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end
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@buffer << result.to_s if result.is_a? String || (result.respond_to?(:acts_as_string?) && result.acts_as_string?) # For convience we push the last return value on if its a string
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@buffer << result if result.is_a?(Element) && @buffer.count == 0
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run_child_block(name.nil?, &block)
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if name
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buffer = @buffer.dup
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React.create_element(name, *args) { buffer }.tap do |element|
@@ -44,7 +32,6 @@ def self.render(name, *args, &block)
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end
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elsif name.is_a? React::Element
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element = name
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# I BELIEVE WAITING ON RESOURCES SHOULD ALREADY BE SET
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else
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element = React.create_element(name, *args)
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element.waiting_on_resources = waiting_on_resources
@@ -78,6 +65,51 @@ def self.remove_nodes_from_args(args)
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value.as_node if value.is_a?(Element) rescue nil
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end if args[0] && args[0].is_a?(Hash)
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end
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# run_child_block gathers the element(s) generated by a child block.
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# for example when rendering this div: div { "hello".span; "goodby".span }
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# two child Elements will be generated.
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#
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# the final value of the block should either be
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# 1 an object that responds to :acts_as_string?
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# 2 a string,
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# 3 an element that is NOT yet pushed on the rendering buffer
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# 4 or the last element pushed on the buffer
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#
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# in case 1 we change the object to a string, and then it becomes case 2
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# in case 2 we automatically push the string onto the buffer
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# in case 3 we also push the Element onto the buffer IF the buffer is empty
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# case 4 requires no special processing
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#
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# Once we have taken care of these special cases we do a check IF we are in an
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# outer rendering scope. In this case react only allows us to generate 1 Element
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# so we insure that is the case, and also check to make sure that element in the buffer
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# is the element returned
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def self.run_child_block(is_outer_scope)
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result = yield
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result = result.to_s if result.try :acts_as_string?
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@buffer << result if result.is_a?(String) || (result.is_a?(Element) && @buffer.empty?)
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raise_render_error(result) if is_outer_scope && @buffer != [result]
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end
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# heurestically raise a meaningful error based on the situation
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def self.raise_render_error(result)
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improper_render 'A different element was returned than was generated within the DSL.',
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'Possibly improper use of Element#delete.' if @buffer.count == 1
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improper_render "Instead #{@buffer.count} elements were generated.",
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'Do you want to wrap your elements in a div?' if @buffer.count > 1
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improper_render "Instead the component #{result} was returned.",
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"Did you mean #{result}()?" if result.try :reactrb_component?
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improper_render "Instead the #{result.class} #{result} was returned.",
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'You may need to convert this to a string.'
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end
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def self.improper_render(message, solution)
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raise "a component's render method must generate and return exactly 1 element or a string.\n"\
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" #{message} #{solution}"
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end
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end
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class ::Object

‎spec/react/component_spec.rb

Lines changed: 52 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -496,6 +496,58 @@ def render; "hello" end
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end
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end
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describe 'Render Error Handling' do
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before(:each) do
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%x{
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window.test_log = [];
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window.org_warn_console = window.console.warn;
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window.org_error_console = window.console.error
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window.console.warn = window.console.error = function(str){window.test_log.push(str)}
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}
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end
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it "will generate a message if render returns something other than an Element or a String" do
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foo = Class.new(React::Component::Base)
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foo.class_eval do
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def render; Hash.new; end
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end
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renderToDocument(foo)
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`window.console.warn = window.org_warn_console; window.console.error = window.org_error_console;`
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expect(`test_log`.first).to match /Instead the Hash \{\} was returned/
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end
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it "will generate a message if render returns a Component class" do
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stub_const 'Foo', Class.new(React::Component::Base)
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foo = Class.new(React::Component::Base)
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foo.class_eval do
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def render; Foo; end
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end
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renderToDocument(foo)
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`window.console.warn = window.org_warn_console; window.console.error = window.org_error_console;`
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expect(`test_log`.first).to match /Did you mean Foo()/
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end
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it "will generate a message if more than 1 element is generated" do
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foo = Class.new(React::Component::Base)
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foo.class_eval do
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def render; "hello".span; "goodby".span; end
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end
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renderToDocument(foo)
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`window.console.warn = window.org_warn_console; window.console.error = window.org_error_console;`
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expect(`test_log`.first).to match /Instead 2 elements were generated/
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end
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it "will generate a message if the element generated is not the element returned" do
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foo = Class.new(React::Component::Base)
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foo.class_eval do
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def render; "hello".span; "goodby".span.delete; end
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end
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renderToDocument(foo)
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`window.console.warn = window.org_warn_console; window.console.error = window.org_error_console;`
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expect(`test_log`.first).to match /A different element was returned than was generated within the DSL/
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end
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end
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describe 'Event handling' do
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before do
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stub_const 'Foo', Class.new

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