diff options
Diffstat (limited to 'activesupport/lib/active_support/testing/assertions.rb')
| -rw-r--r-- | activesupport/lib/active_support/testing/assertions.rb | 129 |
1 files changed, 122 insertions, 7 deletions
diff --git a/activesupport/lib/active_support/testing/assertions.rb b/activesupport/lib/active_support/testing/assertions.rb index 29305e0082..a891ff616d 100644 --- a/activesupport/lib/active_support/testing/assertions.rb +++ b/activesupport/lib/active_support/testing/assertions.rb @@ -1,8 +1,10 @@ -require 'active_support/core_ext/object/blank' +# frozen_string_literal: true module ActiveSupport module Testing module Assertions + UNTRACKED = Object.new # :nodoc: + # Asserts that an expression is not truthy. Passes if <tt>object</tt> is # +nil+ or +false+. "Truthy" means "considered true in a conditional" # like <tt>if foo</tt>. @@ -19,6 +21,17 @@ module ActiveSupport assert !object, message end + # Assertion that the block should not raise an exception. + # + # Passes if evaluated code in the yielded block raises no exception. + # + # assert_nothing_raised do + # perform_service(param: 'no_exception') + # end + def assert_nothing_raised + yield + end + # Test numeric difference between the return value of an expression as a # result of what is evaluated in the yielded block. # @@ -45,6 +58,12 @@ module ActiveSupport # post :create, params: { article: {...} } # end # + # A hash of expressions/numeric differences can also be passed in and evaluated. + # + # assert_difference ->{ Article.count } => 1, ->{ Notification.count } => 2 do + # post :create, params: { article: {...} } + # end + # # A lambda or a list of lambdas can be passed in and evaluated: # # assert_difference ->{ Article.count }, 2 do @@ -60,20 +79,28 @@ module ActiveSupport # assert_difference 'Article.count', -1, 'An Article should be destroyed' do # post :delete, params: { id: ... } # end - def assert_difference(expression, difference = 1, message = nil, &block) - expressions = Array(expression) + def assert_difference(expression, *args, &block) + expressions = + if expression.is_a?(Hash) + message = args[0] + expression + else + difference = args[0] || 1 + message = args[1] + Hash[Array(expression).map { |e| [e, difference] }] + end - exps = expressions.map { |e| + exps = expressions.keys.map { |e| e.respond_to?(:call) ? e : lambda { eval(e, block.binding) } } before = exps.map(&:call) retval = yield - expressions.zip(exps).each_with_index do |(code, e), i| - error = "#{code.inspect} didn't change by #{difference}" + expressions.zip(exps, before) do |(code, diff), exp, before_value| + error = "#{code.inspect} didn't change by #{diff}" error = "#{message}.\n#{error}" if message - assert_equal(before[i] + difference, e.call, error) + assert_equal(before_value + diff, exp.call, error) end retval @@ -94,6 +121,94 @@ module ActiveSupport def assert_no_difference(expression, message = nil, &block) assert_difference expression, 0, message, &block end + + # Assertion that the result of evaluating an expression is changed before + # and after invoking the passed in block. + # + # assert_changes 'Status.all_good?' do + # post :create, params: { status: { ok: false } } + # end + # + # You can pass the block as a string to be evaluated in the context of + # the block. A lambda can be passed for the block as well. + # + # assert_changes -> { Status.all_good? } do + # post :create, params: { status: { ok: false } } + # end + # + # The assertion is useful to test side effects. The passed block can be + # anything that can be converted to string with #to_s. + # + # assert_changes :@object do + # @object = 42 + # end + # + # The keyword arguments :from and :to can be given to specify the + # expected initial value and the expected value after the block was + # executed. + # + # assert_changes :@object, from: nil, to: :foo do + # @object = :foo + # end + # + # An error message can be specified. + # + # assert_changes -> { Status.all_good? }, 'Expected the status to be bad' do + # post :create, params: { status: { incident: true } } + # end + def assert_changes(expression, message = nil, from: UNTRACKED, to: UNTRACKED, &block) + exp = expression.respond_to?(:call) ? expression : -> { eval(expression.to_s, block.binding) } + + before = exp.call + retval = yield + + unless from == UNTRACKED + error = "#{expression.inspect} isn't #{from.inspect}" + error = "#{message}.\n#{error}" if message + assert from === before, error + end + + after = exp.call + + error = "#{expression.inspect} didn't change" + error = "#{error}. It was already #{to}" if before == to + error = "#{message}.\n#{error}" if message + assert before != after, error + + unless to == UNTRACKED + error = "#{expression.inspect} didn't change to #{to}" + error = "#{message}.\n#{error}" if message + assert to === after, error + end + + retval + end + + # Assertion that the result of evaluating an expression is not changed before + # and after invoking the passed in block. + # + # assert_no_changes 'Status.all_good?' do + # post :create, params: { status: { ok: true } } + # end + # + # An error message can be specified. + # + # assert_no_changes -> { Status.all_good? }, 'Expected the status to be good' do + # post :create, params: { status: { ok: false } } + # end + def assert_no_changes(expression, message = nil, &block) + exp = expression.respond_to?(:call) ? expression : -> { eval(expression.to_s, block.binding) } + + before = exp.call + retval = yield + after = exp.call + + error = "#{expression.inspect} did change to #{after}" + error = "#{message}.\n#{error}" if message + assert before == after, error + + retval + end end end end |