#first now raises when no matching elements

Author: twalpole

History.md

@@ -1,6 +1,14 @@
 # Version 3.0.0
+
 Release date: unreleased
 
+### Added
+
+* Ruby 2.2+ required
+* RSpec 2.x no longer supported
+* Deprecated methods removed
+* `first` now raises ElementNotFound by default instead of returning nil, when no matches are found  - Issue #1507
+
 # Version 2.17.0
 Release date: 2018-01-02
 
@@ -244,6 +252,7 @@ Release date: 2016-10-05
 Release date: 2016-09-29
 
 ### Fixed
+
 * :label built-in selector finds nested label/control by control id if the label has no 'for' attribute [Thomas Walpole]
 * Warning issued if an unknown selector type is specified [Thomas Walpole]
 

lib/capybara.rb

@@ -51,8 +51,6 @@ class << self
     #   See {Capybara.configure}
     # @!method always_include_port
     #   See {Capybara.configure}
-    # @!method wait_on_first_by_default
-    #   See {Capybara.configure}
     SessionConfig::OPTIONS.each do |method|
       def_delegators :config, method, "#{method}="
     end
@@ -79,7 +77,6 @@ class << self
     # [ignore_hidden_elements = Boolean]  Whether to ignore hidden elements on the page (Default: true)
     # [automatic_reload = Boolean]        Whether to automatically reload elements as Capybara is waiting (Default: true)
     # [save_path = String]  Where to put pages saved through save_(page|screenshot), save_and_open_(page|screenshot) (Default: Dir.pwd)
-    # [wait_on_first_by_default = Boolean]   Whether Node#first defaults to Capybara waiting behavior for at least 1 element to match (Default: false)
     # [automatic_label_click = Boolean]   Whether Node#choose, Node#check, Node#uncheck will attempt to click the associated label element if the checkbox/radio button are non-visible (Default: false)
     # [enable_aria_label = Boolean]  Whether fields, links, and buttons will match against aria-label attribute (Default: false)
     # [reuse_server = Boolean]  Reuse the server thread between multiple sessions using the same app object (Default: true)
@@ -464,7 +461,6 @@ module Selenium; end
   config.raise_server_errors = true
   config.server_errors = [StandardError]
   config.visible_text_only = false
-  config.wait_on_first_by_default = false
   config.automatic_label_click = false
   config.enable_aria_label = false
   config.reuse_server = true

lib/capybara/node/finders.rb

@@ -271,24 +271,19 @@ def all(*args, &optional_filter_block)
       ##
       #
       # Find the first element on the page matching the given selector
-      # and options, or nil if no element matches.  By default no waiting
-      # behavior occurs, however if {Capybara.wait_on_first_by_default} is set to true
-      # it will trigger Capybara's waiting behavior for a minimum of 1 matching element to be found and
-      # return the first.  Waiting behavior can also be triggered by passing in any of the count
-      # expectation options.
+      # and options.  Will raise an error if no matching element is found
       #
       # @overload first([kind], locator, options)
       #   @param [:css, :xpath] kind                 The type of selector
       #   @param [String] locator                    The selector
       #   @param [Hash] options                      Additional options; see {#all}
       # @return [Capybara::Node::Element]            The found element or nil
       #
-      def first(*args, **options, &optional_filter_block)
-        if session_options.wait_on_first_by_default
-          options = {minimum: 1}.merge(options)
-        end
+      def first(*args, allow_nil: false, **options, &optional_filter_block)
+        options = {minimum: 1}.merge(options)
         all(*args, **options, &optional_filter_block).first
-      rescue Capybara::ExpectationNotMet
+      rescue Capybara::ElementNotFound
+        raise unless allow_nil
         nil
       end
 

lib/capybara/session/config.rb

@@ -4,7 +4,7 @@
 module Capybara
   class SessionConfig
     OPTIONS = [:always_include_port, :run_server, :default_selector, :default_max_wait_time, :ignore_hidden_elements,
-               :automatic_reload, :match, :exact, :exact_text, :raise_server_errors, :visible_text_only, :wait_on_first_by_default,
+               :automatic_reload, :match, :exact, :exact_text, :raise_server_errors, :visible_text_only,
                :automatic_label_click, :enable_aria_label, :save_path, :exact_options, :asset_host, :default_host, :app_host,
                :save_and_open_page_path, :server_host, :server_port, :server_errors]
 
@@ -31,8 +31,6 @@ class SessionConfig
     #  See {Capybara.configure}
     #@!method visible_text_only
     #  See {Capybara.configure}
-    #@!method wait_on_first_by_default
-    #  See {Capybara.configure}
     #@!method automatic_label_click
     #  See {Capybara.configure}
     #@!method enable_aria_label

lib/capybara/spec/session/first_spec.rb

@@ -9,8 +9,14 @@
     expect(@session.first("//input[@id='test_field']").value).to eq('monkey')
   end
 
-  it "should return nil when nothing was found" do
-    expect(@session.first('//div[@id="nosuchthing"]')).to be_nil
+  it "should raise ElementNotFound when nothing was found" do
+    expect do
+      @session.first('//div[@id="nosuchthing"]')
+    end.to raise_error Capybara::ElementNotFound
+  end
+
+  it "should return nil when nothing was found if count options allow no results" do
+    expect(@session.first('//div[@id="nosuchthing"]', minimum: 0)).to be_nil
   end
 
   it "should accept an XPath instance" do
@@ -22,7 +28,7 @@
 
   it "should warn when unused parameters are passed" do
     expect_any_instance_of(Kernel).to receive(:warn).with(/Unused parameters passed.*unused text/)
-    @session.first(:css, '.header h2', 'unused text')
+    @session.first(:css, 'h1', 'unused text')
   end
 
   context "with css selectors" do
@@ -49,40 +55,52 @@
 
   context "with visible filter" do
     it "should only find visible nodes when true" do
-      expect(@session.first(:css, "a#invisible", visible: true)).to be_nil
+      expect do
+        @session.first(:css, "a#invisible", visible: true)
+      end.to raise_error Capybara::ElementNotFound
     end
 
     it "should find nodes regardless of whether they are invisible when false" do
-      expect(@session.first(:css, "a#invisible", visible: false)).not_to be_nil
-      expect(@session.first(:css, "a#invisible", visible: false, text: 'hidden link')).not_to be_nil
-      expect(@session.first(:css, "a#visible", visible: false)).not_to be_nil
+      expect(@session.first(:css, "a#invisible", visible: false)).to be
+      expect(@session.first(:css, "a#invisible", visible: false, text: 'hidden link')).to be
+      expect(@session.first(:css, "a#visible", visible: false)).to be
     end
 
     it "should find nodes regardless of whether they are invisible when :all" do
-      expect(@session.first(:css, "a#invisible", visible: :all)).not_to be_nil
-      expect(@session.first(:css, "a#invisible", visible: :all, text: 'hidden link')).not_to be_nil
-      expect(@session.first(:css, "a#visible", visible: :all)).not_to be_nil
+      expect(@session.first(:css, "a#invisible", visible: :all)).to be
+      expect(@session.first(:css, "a#invisible", visible: :all, text: 'hidden link')).to be
+      expect(@session.first(:css, "a#visible", visible: :all)).to be
     end
 
     it "should find only hidden nodes when :hidden" do
-      expect(@session.first(:css, "a#invisible", visible: :hidden)).not_to be_nil
-      expect(@session.first(:css, "a#invisible", visible: :hidden, text: 'hidden link')).not_to be_nil
-      expect(@session.first(:css, "a#invisible", visible: :hidden, text: 'not hidden link')).to be_nil
-      expect(@session.first(:css, "a#visible", visible: :hidden)).to be_nil
+      expect(@session.first(:css, "a#invisible", visible: :hidden)).to be
+      expect(@session.first(:css, "a#invisible", visible: :hidden, text: 'hidden link')).to be
+      expect do
+        @session.first(:css, "a#invisible", visible: :hidden, text: 'not hidden link')
+      end.to raise_error Capybara::ElementNotFound
+      expect do
+        @session.first(:css, "a#visible", visible: :hidden)
+      end.to raise_error Capybara::ElementNotFound
     end
 
     it "should find only visible nodes when :visible" do
-      expect(@session.first(:css, "a#invisible", visible: :visible)).to be_nil
-      expect(@session.first(:css, "a#invisible", visible: :visible, text: 'hidden link')).to be_nil
-      expect(@session.first(:css, "a#visible", visible: :visible)).not_to be_nil
+      expect do
+        @session.first(:css, "a#invisible", visible: :visible)
+      end.to raise_error Capybara::ElementNotFound
+      expect do
+        @session.first(:css, "a#invisible", visible: :visible, text: 'hidden link')
+      end.to raise_error Capybara::ElementNotFound
+      expect(@session.first(:css, "a#visible", visible: :visible)).to be
     end
 
     it "should default to Capybara.ignore_hidden_elements" do
       Capybara.ignore_hidden_elements = true
-      expect(@session.first(:css, "a#invisible")).to be_nil
+      expect do
+        @session.first(:css, "a#invisible")
+      end.to raise_error Capybara::ElementNotFound
       Capybara.ignore_hidden_elements = false
-      expect(@session.first(:css, "a#invisible")).not_to be_nil
-      expect(@session.first(:css, "a")).not_to be_nil
+      expect(@session.first(:css, "a#invisible")).to be
+      expect(@session.first(:css, "a")).to be
     end
   end
 
@@ -93,35 +111,34 @@
 
     it "should find the first element using the given locator" do
       @session.within(:xpath, "//div[@id='for_bar']") do
-        expect(@session.first('.//form')).not_to be_nil
+        expect(@session.first('.//form')).to be
       end
     end
   end
 
-  context "with Capybara.wait_on_first_by_default", requires: [:js] do
+  context "waiting behavior", requires: [:js] do
     before do
       @session.visit('/with_js')
     end
 
-    it "should not wait if false" do
-      Capybara.wait_on_first_by_default = false
+    it "should not wait if minimum: 0" do
       @session.click_link('clickable')
-      expect(@session.first(:css, 'a#has-been-clicked')).to be_nil
+      expect(@session.first(:css, 'a#has-been-clicked', minimum: 0)).to be_nil
     end
 
-    it "should wait for at least one match if true" do
-      Capybara.wait_on_first_by_default = true
+    it "should wait for at least one match by default" do
       Capybara.using_wait_time(3) do
         @session.click_link('clickable')
         expect(@session.first(:css, 'a#has-been-clicked')).not_to be_nil
       end
     end
 
-    it "should return nil after waiting if no match" do
-      Capybara.wait_on_first_by_default = true
+    it "should return nil after waiting if no match and allow_nil is true" do
+      @session.click_link('clickable')
+      start_time = Time.now
       Capybara.using_wait_time(3) do
-        @session.click_link('clickable')
-        expect(@session.first(:css, 'a#not-a-real-link')).to be_nil
+        expect(@session.first(:css, 'a#not-a-real-link', allow_nil: true)).to be_nil
+        expect(Time.now-start_time).to be > 3
       end
     end
   end

lib/capybara/spec/spec_helper.rb

@@ -30,7 +30,6 @@ def reset!
         Capybara.raise_server_errors = true
         Capybara.visible_text_only = false
         Capybara.match = :smart
-        Capybara.wait_on_first_by_default = false
         Capybara.enable_aria_label = false
         reset_threadsafe
       end

spec/per_session_config_spec.rb

@@ -9,7 +9,7 @@
       session = Capybara::Session.new(:rack_test, TestApp)
       [:default_host, :app_host, :save_and_open_page_path,
        :always_include_port, :run_server, :default_selector, :default_max_wait_time, :ignore_hidden_elements,
-       :automatic_reload, :match, :exact, :raise_server_errors, :visible_text_only, :wait_on_first_by_default,
+       :automatic_reload, :match, :exact, :raise_server_errors, :visible_text_only,
        :automatic_label_click, :enable_aria_label,
        :save_path, :exact_options, :asset_host].each do |m|
          expect(session.config.public_send(m)).to eq Capybara.public_send(m)