Test-first-ruby 13_xml_document - ruby-on-rails

Question

I am working on test-first-ruby-master (you can find it at https://github.com/appacademy/test-first-ruby).
The 13_xml_document_spec.rb is the Rspec test that my code must pass. This test has several tasks, but it is the last one (called "indents") that my code doesn't accomplish.
Here is the Rspec test:
require "13_xml_document"
describe XmlDocument do
before do
#xml = XmlDocument.new
end
it "renders an empty tag" do
expect(#xml.hello).to eq("<hello/>")
end
it "renders a tag with attributes" do
expect(#xml.hello(:name => "dolly")).to eq('<hello name="dolly"/>')
end
it "renders a randomly named tag" do
tag_name = (1..8).map{|i| ("a".."z").to_a[rand(26)]}.join
expect(#xml.send(tag_name)).to eq("<#{tag_name}/>")
end
it "renders block with text inside" do
expect(#xml.hello { "dolly" }).to eq("<hello>dolly</hello>")
end
it "nests one level" do
expect(#xml.hello { #xml.goodbye }).to eq("<hello><goodbye/></hello>")
end
it "nests several levels" do
xml = XmlDocument.new
xml_string = xml.hello do
xml.goodbye do
xml.come_back do
xml.ok_fine(:be => "that_way")
end
end
end
expect(xml_string).to eq('<hello><goodbye><come_back><ok_fine
be="that_way"/></come_back></goodbye></hello>')
end
it "indents" do
#xml = XmlDocument.new(true)
xml_string = #xml.hello do
#xml.goodbye do
#xml.come_back do
#xml.ok_fine(:be => "that_way")
end
end
end
expect(xml_string).to eq(
"<hello>\n" +
" <goodbye>\n" +
" <come_back>\n" +
" <ok_fine be=\"that_way\"/>\n" +
" </come_back>\n" +
" </goodbye>\n" +
"</hello>\n"
)
end
end
And here is my code:
class XmlDocument
def initialize(indentation = false)
#indentation = indentation
#counter = 0
end
def method_missing(method, *args, &block)
hash = {}
if block
if #indentation == false
"<#{method}>#{yield}</#{method}>"
elsif #indentation == true
string = ""
string << indent1
string << "<#{method}>\n"
(###)
add_indent
string << indent1
string << yield + "\n"
sub_indent
string << indent2
string << "</#{method}\>"
string
end
elsif args[0].is_a?(Hash)
args[0].map { |key,value| "<#{method.to_s} #{key.to_s}=\"#{value.to_s}\"/>" }.join(" ")
elsif hash.empty?
"<#{method.to_s}/>"
end
end
def indent1
" " * #counter
end
def indent2
" " * #counter
end
def add_indent
#counter += 1
end
def sub_indent
#counter -= 1
end
end
This is the output I get for the "indents" part:
<hello>
<goodbye>
<come_back>
+ <ok_fine be="that_way"/>
</come_back>
</goodbye>
</hello>
Contrary to the right answer, the 4th line ('ok_fine be="that_way"/') seems be two indents closer to the left than it is supposed to be. As opposed to the rest of the lines, the 4th line is not a block, but an argument of the called method 'come_back'.
I cannot see where my mistake is. Even writing an exception in the code (where the (###) is in my code) doesn't seem to have any effect on the 4th line.
Here is the exception (###):
if args[0].is_a?(Hash)
add_indent
string << indent
arg[0].map{|key, value| string << "<#{method.to_s} #{key.to_s}=\"#{value.to_s}\"/>"}
end
NOTE: I assume that if I manage to give the 4th line the right numbers of indents, that also will increase the number of indents of the lines after it, so the method 'indent2' will need to be modified.

Answer 1

I figured out what the problem was. As I said in my question, in the Rspec test they have the following input:
xml_string = xml.hello do
xml.goodbye do
xml.come_back do
xml.ok_fine(:be => "that_way")
end
end
end
where the 4th line (xml.ok_fine(:be => "that_way")) doesn't have a block nested, but an argument. In my code I established a condition (if block) for when there is a block present and inside this first condition, a second condition (if #indentation == true) for when #indentation is true:
if block
if #indentation == false
"<#{method}>#{yield}</#{method}>"
elsif #indentation == true
...
It is inside this second condition that I create the variable 'string' where I shovel in the different parts:
elsif #indentation == true
string = ""
string << indent1
string << "<#{method}>\n"
(###)
add_indent
string << indent1
string << yield + "\n"
sub_indent
string << indent2
string << "</#{method}\>"
string
end
But because the 4th line doesn't carry a block, the first condition (if block) doesn't return true for it and therefore this 4th line is skipped.
I've re-written my code so now it passes the Rspec test:
class XmlDocument
def initialize(indentation = false)
#indentation = indentation
#counter = 0
end
def method_missing(method, args = nil, &block)
string = ""
arguments = args
if #indentation == false
if (arguments == nil) && (block == nil)
"<#{method.to_s}/>"
elsif arguments.is_a?(Hash)
arguments.map { |key,value| "<#{method.to_s} #{key.to_s}=\"#{value.to_s}\"/>" }.join(" ")
elsif block
"<#{method}>#{yield}</#{method}>"
end
elsif #indentation == true
if (block) || (arguments.is_a?(Hash))
string << indent1
string << "<#{method}>\n" unless !block
add_indent
string << indent1 unless !block
if block
string << yield + "\n"
elsif arguments.is_a?(Hash)
arguments.map { |key,value| string << "<#{method.to_s} #{key.to_s}=\"#{value.to_s}\"/>" }
end
sub_indent
string << indent2 unless !block
string << "</#{method}\>" unless !block
if indent2 == ""
string << "\n"
end
end
string
end
end
def indent1
" " * #counter
end
def indent2
" " * #counter
end
def add_indent
#counter += 1
end
def sub_indent
#counter -= 1
end
end
In contrast to the code I wrote in my question, in this one, the two main conditions are #indentation == false and #indentation == true and inside these two conditions I establish different exceptions for the different cases (block or no block, argument or no argument...). Specifically for elsif #indentation == true I created a condition that accepts the 4th line: if (block) || (arguments.is_a?(Hash)), or in other words, it accepts methods that have a block or an argument (especifically a a hash).
Now, I shovel in the different parts in 'string', and when I reach a block to yield there is a bifurcation:
if block
string << yield + "\n"
elsif arguments.is_a?(Hash)
arguments.map { |key,value| string << "<#{method.to_s} #{key.to_s}=\"#{value.to_s}\"/>" }
if there is a block I "yield" it, and if there is and argument that is a hash I shovel it into 'string'.
Also, there is this exception unless !block either when I indent or I shovel a method because otherwise it can introduce unwanted indents and '\n' if there is a method that doesn't have a block (as line 4th).
Finally, I had to add at the end
if indent2 == ""
string << "\n"
end
because the solution requires a '\n' at the end.
I hope this answer can help other
NOTE: I wrote a 'NOTE' in my question where I assumed I would have to modify 'indent2'. That, obviously I didn't have to do because the output I was getting did not considered the 4th line (because it doesn't have a block), so the bigger indentation (" ") of 'indent2' is all right.