Handle more edge cases

lib/snapshot.rb

@@ -9,7 +9,9 @@ class Snapshot
 
   def quote
     self.date = if date
-      Currency.where("date <= '#{date}'").order(:date).last.date
+      last_date = Currency.where("date <= '#{date}'").order(:date).last
+      raise ArgumentError.new('Date too old') unless last_date
+      last_date.date
     else
       Currency.last_date
     end
@@ -28,6 +30,7 @@ class Snapshot
   def rebase(rates)
     if base.upcase! != 'EUR'
       denominator = rates.update('EUR' => 1.0).delete(base)
+      raise ArgumentError.new('Invalid base') unless denominator
 
       rates.each do |iso_code, rate|
         rates[iso_code] = round(rate / denominator)

spec/api_spec.rb

@@ -7,7 +7,6 @@ describe 'the API' do
 
   let(:app)  { Sinatra::Application }
   let(:json) { Yajl::Parser.new.parse last_response.body }
-  let(:status) { last_response.status }
 
   it 'returns latest snapshot' do
     get '/latest'
@@ -34,14 +33,4 @@ describe 'the API' do
     get '/2010-01-01'
     json['rates'].wont_be :empty?
   end
-
-  it 'considers an invalid date unprocessable' do
-    get '/2010-31-01'
-    last_response.must_be :unprocessable?
-  end
-
-  it 'handles unfound pages' do
-    get '/'
-    last_response.status.must_equal 404
-  end
 end

spec/edge_cases_spec.rb

@@ -0,0 +1,29 @@
+require_relative 'helper'
+require 'rack/test'
+require 'api'
+
+describe 'the API' do
+  include Rack::Test::Methods
+
+  let(:app)  { Sinatra::Application }
+
+  it 'handles unfound pages' do
+    get '/'
+    last_response.status.must_equal 404
+  end
+
+  it 'will not process an invalid date' do
+    get '/2010-31-01'
+    last_response.must_be :unprocessable?
+  end
+
+  it 'will not process a date before 2000' do
+    get '/1999-01-01'
+    last_response.must_be :unprocessable?
+  end
+
+  it 'will not process an invalid base' do
+    get '/latest?base=UAH'
+    last_response.must_be :unprocessable?
+  end
+end