rspec users - Apr 2011 - Faking Files, Data, Git interractions with mocks/stubs/fixtures

I''m new to ruby and just learning cucumber and rspec. I have some
examples(tests) that need to fake a directory structure and file
grouping, fake a properly formatted json file and fake a ruby-git
interraction (git.fetch, git.merge).

I''ve been reading about mocks and stubs but still feeling a little in
the dark.

Given some example tests like the following

describe "#update_repo" do
   it "should update the repository without errors" do
        git = double(''git'')
        # How do I mock this so that the Git object is "faked" and the
calls to fetch/merge don''t cause an error without actually talking to a
remote repo
        lambda { @app.update_repo git }.should_not raise_error
   end
end

describe "#check_json" do
   it "should check that the har files are valid json if they exist"
do
         # In the real context @app.files contains a list of har json
files
         # How do I mock the json files on the file system
         test_contents = @app.organize_test_contents @app.files
         # Can I mock test_contents or use a fixture?
         result = @app.check_json test_contents
         result.should =~ /JSON Valid/
   end
end

What are some recommended ways for faking data, faking file systems,
faking network interractions

-- 
Posted via http://www.ruby-forum.com/.

On 19 Apr 2011, at 19:24, Josh N. wrote:
> I''m new to ruby and just learning cucumber and rspec. I have some
> examples(tests) that need to fake a directory structure and file
> grouping, fake a properly formatted json file and fake a ruby-git
> interraction (git.fetch, git.merge).
> 
> I''ve been reading about mocks and stubs but still feeling a little
in
> the dark.
> 
> Given some example tests like the following
> 
> describe "#update_repo" do
>   it "should update the repository without errors" do
>        git = double(''git'')
>        # How do I mock this so that the Git object is "faked" and
the
> calls to fetch/merge don''t cause an error without actually talking
to a
> remote repo
>        lambda { @app.update_repo git }.should_not raise_error
>   end
> end
> 
> describe "#check_json" do
>   it "should check that the har files are valid json if they
exist" do
>         # In the real context @app.files contains a list of har json
> files
>         # How do I mock the json files on the file system
>         test_contents = @app.organize_test_contents @app.files
>         # Can I mock test_contents or use a fixture?
>         result = @app.check_json test_contents
>         result.should =~ /JSON Valid/
>   end
> end
> 
> What are some recommended ways for faking data, faking file systems,
> faking network interractions
Quick answer:

One well-trodden path is to use the adapter pattern to isolate the behaviour
that actually interacts with the external file / network system behind an
interface. I''d recommend Steve Freeman and Nat Pryce''s book
"Growing Object Oriented Software, Guided by Tests" (GOOS) where they
talk about this in detail, as well as many other very useful testing techniques.
The examples are in java, but the design principles apply equally to Ruby code.
> 
> -- 
> Posted via http://www.ruby-forum.com/.
> _______________________________________________
> rspec-users mailing list
> rspec-users at rubyforge.org
> http://rubyforge.org/mailman/listinfo/rspec-users
cheers,
Matt

matt at mattwynne.net
07974 430184

I''ve been using the VCR gem lately and it is great.
Maybe this would be useful if you''re fetching from git using http??
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<http://rubyforge.org/pipermail/rspec-users/attachments/20110421/eff8938d/attachment.html>