Raise instead of warn on long-deprecated usages

Changelog.md

@@ -9,6 +9,10 @@ Breaking Changes:
 * Change the default `shared_context_metadata_behavior` to `apply_to_host_groups`
   and remove the configuration option. (Phil Pirozhkov, #2834)
 * Remove `run_all_when_everything_filtered` configuration option. (Phil Pirozhkov, #2845)
+* Raise on unsupported hook scope usage. (Phil Pirozhkov, #2849)
+* Raise on usage of metadata on suite-level scopes. (Phil Pirozhkov, #2849)
+* Raise an error when `fail_fast` is configured with
+  an unsupported value. (Phil Pirozhkov, #2849)
 
 Enhancements:
 

lib/rspec/core/configuration.rb

@@ -203,11 +203,9 @@ def fail_fast=(value)
           @fail_fast = value.to_i
 
           if value.to_i == 0
-            # TODO: in RSpec 4, consider raising an error here.
-            RSpec.warning "Cannot set `RSpec.configuration.fail_fast`" \
+            raise ArgumentError, "Cannot set `RSpec.configuration.fail_fast`" \
               " to `#{value.inspect}`. Only `true`, `false`, `nil` and integers" \
               " are valid values."
-            @fail_fast = true
           end
         end
       end
@@ -1990,9 +1988,7 @@ def handle_suite_hook(scope, meta)
         return nil unless scope == :suite
 
         unless meta.empty?
-          # TODO: in RSpec 4, consider raising an error here.
-          # We warn only for backwards compatibility.
-          RSpec.warn_with "WARNING: `:suite` hooks do not support metadata since " \
+          raise ArgumentError, "WARNING: `:suite` hooks do not support metadata since " \
                           "they apply to the suite as a whole rather than " \
                           "any individual example or example group that has metadata. " \
                           "The metadata you have provided (#{meta.inspect}) will be ignored."

lib/rspec/core/hooks.rb

@@ -442,18 +442,13 @@ def register(prepend_or_append, position, *args, &block)
           scope, options = scope_and_options_from(*args)
 
           if scope == :suite
-            # TODO: consider making this an error in RSpec 4. For SemVer reasons,
-            # we are only warning in RSpec 3.
-            RSpec.warn_with "WARNING: `#{position}(:suite)` hooks are only supported on " \
-                            "the RSpec configuration object. This " \
-                            "`#{position}(:suite)` hook, registered on an example " \
-                            "group, will be ignored."
-            return
+            raise ArgumentError, "`#{position}(:suite)` hooks are only " \
+              "supported on the RSpec configuration object. This " \
+              "`#{position}(:suite)` hook, registered on an example " \
+              "group, will be ignored."
           elsif scope == :context && position == :around
-            # TODO: consider making this an error in RSpec 4. For SemVer reasons,
-            # we are only warning in RSpec 3.
-            RSpec.warn_with "WARNING: `around(:context)` hooks are not supported and " \
-                            "behave like `around(:example)."
+            raise ArgumentError, "`around(:context)` hooks are not supported " \
+              "and behave like `around(:example)`."
           end
 
           hook = HOOK_TYPES[position][scope].new(block, options)

spec/rspec/core/configuration_spec.rb

@@ -110,14 +110,10 @@ module RSpec::Core
           allow(RSpec).to receive(:warning)
         end
 
-        it 'prints warning' do
-          config.fail_fast = 'yes'
-          expect(RSpec).to have_received(:warning).with(/Cannot set `RSpec.configuration.fail_fast`/i)
-        end
-
-        it 'is set to true' do
-          config.fail_fast = 'yes'
-          expect(config.fail_fast).to eq true
+        it 'raises an error' do
+          expect {
+            config.fail_fast = 'yes'
+          }.to raise_error(ArgumentError, /Cannot set `RSpec.configuration.fail_fast`/i)
         end
       end
     end

spec/rspec/core/hooks_spec.rb

@@ -484,32 +484,30 @@ def yielder
       ])
     end
 
-    it 'emits a warning for `around(:context)`' do
-      expect(RSpec).to receive(:warn_with).with(a_string_including(
-        '`around(:context)` hooks are not supported'
-      ))
-      RSpec.describe do
-        around(:context) { }
-      end
+    it 'raises an error for `around(:context)`' do
+      expect {
+        RSpec.describe do
+          around(:context) { }
+        end
+      }.to raise_error(ArgumentError, a_string_including("`around(:context)` hooks are not supported"))
     end
 
-    it 'emits a warning for `around(:context)` defined in `configure`' do
-      expect(RSpec).to receive(:warn_with).with(a_string_including(
-        '`around(:context)` hooks are not supported'
-      ))
-      RSpec.configure do |c|
-        c.around(:context) { }
-      end
+    it 'raises an error for `around(:context)` defined in `configure`' do
+      expect {
+        RSpec.configure do |c|
+          c.around(:context) { }
+        end
+      }.to raise_error(ArgumentError, a_string_including("`around(:context)` hooks are not supported"))
     end
 
     [:before, :around, :after].each do |type|
       it "emits a warning for `#{type}(:suite)` hooks" do
-        expect(RSpec).to receive(:warn_with).with(a_string_including(
-          "`#{type}(:suite)` hooks are only supported on the RSpec configuration object."
-        ))
-        RSpec.describe do
-          send(type, :suite) { }
-        end
+        expect {
+          RSpec.describe do
+            send(type, :suite) { }
+          end
+        }.to raise_error(ArgumentError, a_string_including(
+          "`#{type}(:suite)` hooks are only supported on the RSpec configuration object"))
       end
     end
   end

spec/rspec/core/suite_hooks_spec.rb

@@ -66,26 +66,22 @@ module RSpec::Core
         end
 
         context "registered on an example group" do
-          it "is ignored with a clear warning" do
-            sequence = []
-
+          it "raises an error with a clear message" do
             expect {
               RSpec.describe "Group" do
-                __send__(registration_method, :suite) { sequence << :suite_hook }
-                example { sequence << :example }
-              end.run
-            }.to change { sequence }.to([:example]).
-              and output(a_string_including("#{type}(:suite)")).to_stderr
+                __send__(registration_method, :suite) { }
+              end
+            }.to raise_error(a_string_including("#{type}(:suite)"))
           end
         end
 
         context "registered with metadata" do
-          it "explicitly warns that the metadata is ignored" do
+          it "raises an error" do
             expect {
               RSpec.configure do |c|
                 c.__send__(registration_method, :suite, :some => :metadata)
               end
-            }.to output(a_string_including(":suite", "metadata")).to_stderr
+            }.to raise_error(ArgumentError, a_string_including(":suite", "metadata"))
           end
         end
       end
@@ -112,17 +108,6 @@ def define_and_run_example_group(&block)
         runner.run err, out
       end
 
-      it "still runs :suite hooks with metadata even though the metadata is ignored" do
-        sequence = []
-        allow(RSpec).to receive(:warn_with)
-
-        config.before(:suite, :foo)  { sequence << :before_suite   }
-        config.after(:suite, :foo)   { sequence << :after_suite    }
-        define_and_run_example_group { sequence << :example_groups }
-
-        expect(sequence).to eq([ :before_suite, :example_groups, :after_suite ])
-      end
-
       it "runs :suite hooks before and after example groups in the correct order" do
         sequence = []