On Jul 5, 2010, at 4:14 AM, Matt Wynne wrote: > On 5 Jul 2010, at 08:00, Wincent Colaiuta wrote: >> Hi folks, >> >> I've been unhappy with routing specs for a long time now and last night when >> updating some old 1.3 specs for 2.0 I decided to see if I could come up with >> something that didn't make me feel unhappy. >> >> Principal causes of unhappiness: >> >> 1. Historically we had "route_for" and "params_from", which felt awfully >> repetitive because we ended up doing: >> >> route_for(lengthy_hash_of_params).should == >> string_or_hash_describing_destination >> params_from(list_describing_destination).should == lengthy_hash_of_params >> >> Of course, it was worse than that in practice because those two lines >> usually appeared in separate example blocks with the associated boilerplate. >> It felt like a lot of work for testing such a simple thing. It also felt >> irritating to have to repeat basically the same thing twice but in a >> different order. >> >> 2. So then RSpec gave us "route_to", which is a wrapper for Rails' >> "assert_routing"; being a bi-directional test that encompasses the function >> of both "assert_recognizes" and "assert_generates", this allows us to avoid >> some, or even all, of the repetition: >> >> { :get => 'foo' }.should route_to(:controller => 'foo', :action => 'index') >> >> The unhappiness here comes from three causes: >> >> One is that { :get => 'foo' } feels inconsistent with other places in RSpec >> like controller specs where "get" is a method, so we can do things like "get >> 'thing'". >> >> The second issue is that the "to" in "route_to" feels misleadingly >> uni-directional when in reality it is a bi-directional test. >> >> The third issue is that for routes which don't actually have that >> bi-directional mapping, "route_to" can't be used and we must instead drop >> down to Rails' assert_recognizes() and/or assert_generates() methods, or >> wrap them using our own matchers.
This is the source of confusion/trouble that others have brought up here on this list as well. Thanks for identifying the underlying issue. >> So I thought about what I would rather be writing and in my first cut came >> up with this: >> >> describe ArticlesController do >> describe 'routing' do >> example 'GET /wiki' do >> get('/wiki').should map_to(:controller => 'articles', :action => >> 'index') >> get('/wiki').should map_from(:controller => 'articles', :action => >> 'index') >> articles_path.should == '/wiki' >> end >> end >> end >> >> Things to note: >> >> - make the bi-directionality of the mapping explicit by having separate >> "map_to" and "map_from" lines. >> >> - for ease of readability and writability, keep the order as "method -> path >> -> destination" for both assertions by using "to" and "from", rather than >> swapping the order around >> >> - "map" here is the right verb because we've always used that language to >> talk about how a given URL "maps to" a given controller#action. And remember >> how in the router DSL prior to Rails 3 everything in config/routes.rb >> started with "map"? >> >> - I've tacked a test for the "articles_path" URL helper in there, because as >> a user of the Rails router I generally want to know two things: firstly, >> that requests get mapped to the appropriate controller#action; and secondly, >> that when I generate URLs (almost exclusively with named helpers; I use >> "url_for" in only 4 places in my entire app) that they take me where I think >> they take me. In the end, however, I moved this into a separate "describe >> 'URL helpers'" block. >> >> - conscious use of "example" rather than "it" because I want my specs to be >> identified as "ArticlesController routing GET /wiki" and not >> "ArticlesController routing recognizes and generates #index". >> >> - the repetition is a conscious choice because I value >> readability/scannability over DRYness-at-all-costs, especially in specs; the >> following is more DRY, for example, but less readable/scannable: >> >> path = '/wiki' >> destination = { :controller => 'articles, :action => 'index' } >> get(path).should map_to(destination) >> get(path).should map_from(destination) >> >> So I went ahead and converted a bunch of specs to this syntax and found >> that, surprise, surprise, in an application like this one where almost >> everything consists of a "standard" RESTful resource, over 90% of routes >> were testable in the bi-directional sense and in a typical routing spec file >> I needed to use "map_to" with no corresponding "map_from" for only one or >> two cases. So I needed a new method that meant "map_to_and_from". >> >> Funnily, I just can't decide on a name for this method. As a placeholder I >> am just using "map" for now: >> >> get('/wiki').should map(:controller => 'articles', :action => 'index') >> >> But others I have tried are: >> >> get('/wiki').should map_as(:controller => 'articles', :action => 'index') >> get('/wiki').should map_via(:controller => 'articles', :action => 'index') >> get('/wiki').should map_with(:controller => 'articles', :action => 'index') >> get('/wiki').should map_to_and_from(:controller => 'articles', :action => >> 'index') >> get('/wiki').should map_both(:controller => 'articles', :action => 'index') >> get('/wiki').should map_both_ways(:controller => 'articles', :action => >> 'index') >> get('/wiki').should have_routing(:controller => 'articles', :action => >> 'index') >> get('/wiki').should have_route(:controller => 'articles', :action => 'index') >> get('/wiki').should be_route(:controller => 'articles', :action => 'index') >> get('/wiki').should be_routing(:controller => 'articles', :action => 'index') >> get('/wiki').should route_as(:controller => 'articles', :action => 'index') >> get('/wiki').should route_via(:controller => 'articles', :action => 'index') >> get('/wiki').should route(:controller => 'articles', :action => 'index') >> get('/wiki').should <=> (:controller => 'articles', :action => 'index') >> get('/wiki').should > (:controller => 'articles', :action => 'index') # >> map_to >> get('/wiki').should < (:controller => 'articles', :action => 'index') # >> map_from >> >> If anybody has a suitable suggestion please let me know. Naming is hard. >> In the meantime, here is an example of a spec file that has been converted >> to use this new "API": >> >> http://gist.github.com/464081 Nice overall. Much of the code belongs in Rails, though, so I'd like to try to get a patch in to Rails once we get this worked out. I'd like the rspec-rails matchers to be simple wrappers for rails' assertions wherever possible. >> It also includes the supporting code that adds these new "map", "map_to", >> "map_from" matchers, and the "get", "post", "put" and "delete" methods. All >> of this for Rails 3/RSpec 2 only. >> >> I'm going to convert more routing specs and see if any more changes are >> needed to handle edge cases, but for a first cut I am pretty happy with the >> results, apart from my inability to decide on the right name for the >> bi-directional "map" matcher. I think having three separate matchers would land us in a good spot. The wrapped rails assertions also accept a hash representing query params, so let's see if we can accommodate that as well: get('/something', :ref_id => '1234').should route_to(....) >> >> Cheers, >> Wincent > > Seems like progress. One thought: Why not use a macro-style syntax to > eliminate the boring boilerplate call to #it / #example and generate examples > instead? Something like: describe "The router" do it { should recognize(get('/wiki/foo').as("wiki#show", :id => 'foo') } it { should generate(get('/wiki/foo').from("wiki#show", :id => 'foo') } it { should route(get('/wiki/foo').to("wiki#show", :id => 'foo') } end That's definitely nice and clean, and it makes it easier to align the names with the rails assertions, which I think adds some value. The output could be formatted something like this: The router should recognize get('/wiki/foo') as wiki#show with :id => 'foo' should generate get('/wiki/foo') from wiki#show with :id => 'foo' should route get('/wiki/foo') to wiki#show with :id => 'foo' Thoughts? _______________________________________________ rspec-users mailing list rspec-users@rubyforge.org http://rubyforge.org/mailman/listinfo/rspec-users