Avoid using heredoc for user warnings

Using heredoc would enforce line wrapping to whatever column width we decided to
use in the code, making it difficult for the users to read on some consoles.

This does make the source code read slightly worse and a bit more error-prone,
but this seems like a fair price to pay since the primary purpose for these
messages are for the users to read and the code will not stick around for too
long.

10 files changed, 51 insertions, 61 deletions

diff --git a/activerecord/lib/active_record/associations/has_many_through_association.rb b/activerecord/lib/active_record/associations/has_many_through_association.rb
index 44c4436e95..0968b0068e 100644
--- a/activerecord/lib/active_record/associations/has_many_through_association.rb
+++ b/activerecord/lib/active_record/associations/has_many_through_association.rb
@@ -63,12 +63,12 @@ module ActiveRecord
 
         save_through_record(record)
         if has_cached_counter? && !through_reflection_updates_counter_cache?
-          ActiveSupport::Deprecation.warn(<<-MESSAGE.strip_heredoc)
-            Automatic updating of counter caches on through associations has been
-            deprecated, and will be removed in Rails 5.0. Instead, please set the
-            appropriate counter_cache options on the has_many and belongs_to for
-            your associations to #{through_reflection.name}.
-          MESSAGE
+          ActiveSupport::Deprecation.warn \
+            "Automatic updating of counter caches on through associations has been " \
+            "deprecated, and will be removed in Rails 5.0. Instead, please set the " \
+            "appropriate counter_cache options on the has_many and belongs_to for " \
+            "your associations to #{through_reflection.name}."
+
           update_counter_in_database(1)
         end
         record
diff --git a/activerecord/lib/active_record/attribute_methods.rb b/activerecord/lib/active_record/attribute_methods.rb
index 1ff28ceccc..ceee96b3a8 100644
--- a/activerecord/lib/active_record/attribute_methods.rb
+++ b/activerecord/lib/active_record/attribute_methods.rb
@@ -203,11 +203,9 @@ module ActiveRecord
       def column_for_attribute(name)
         column = columns_hash[name.to_s]
         if column.nil?
-          ActiveSupport::Deprecation.warn(<<-MESSAGE.strip_heredoc)
-            `column_for_attribute` will return a null object for non-existent columns
-            in Rails 5.0. Use `has_attribute?` if you need to check for an
-            attribute's existence.
-          MESSAGE
+          ActiveSupport::Deprecation.warn \
+            "`column_for_attribute` will return a null object for non-existent columns " \
+            "in Rails 5.0. Use `has_attribute?` if you need to check for an attribute's existence."
         end
         column
       end
diff --git a/activerecord/lib/active_record/attribute_methods/read.rb b/activerecord/lib/active_record/attribute_methods/read.rb
index 10869dfc1e..bf2a084a00 100644
--- a/activerecord/lib/active_record/attribute_methods/read.rb
+++ b/activerecord/lib/active_record/attribute_methods/read.rb
@@ -46,9 +46,7 @@ module ActiveRecord
         protected
 
         def cached_attributes_deprecation_warning(method_name)
-          ActiveSupport::Deprecation.warn(<<-MESSAGE.strip_heredoc)
-            Calling `#{method_name}` is no longer necessary. All attributes are cached.
-          MESSAGE
+          ActiveSupport::Deprecation.warn "Calling `#{method_name}` is no longer necessary. All attributes are cached."
         end
 
         if Module.methods_transplantable?
diff --git a/activerecord/lib/active_record/attribute_methods/serialization.rb b/activerecord/lib/active_record/attribute_methods/serialization.rb
index 264ce2bdfa..100d6d4229 100644
--- a/activerecord/lib/active_record/attribute_methods/serialization.rb
+++ b/activerecord/lib/active_record/attribute_methods/serialization.rb
@@ -54,10 +54,9 @@ module ActiveRecord
         end
 
         def serialized_attributes
-          ActiveSupport::Deprecation.warn(<<-WARNING.strip_heredoc)
-            `serialized_attributes` is deprecated without replacement, and will
-            be removed in Rails 5.0.
-          WARNING
+          ActiveSupport::Deprecation.warn "`serialized_attributes` is deprecated " \
+            "without replacement, and will be removed in Rails 5.0."
+
           @serialized_attributes ||= Hash[
             columns.select { |t| t.cast_type.is_a?(Type::Serialized) }.map { |c|
               [c.name, c.cast_type.coder]
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb
index 92ac607a3c..cf0e3a260d 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb
@@ -61,12 +61,11 @@ module ActiveRecord
       def emit_warning_if_null_unspecified(options)
         return if options.key?(:null)
 
-        ActiveSupport::Deprecation.warn(<<-MESSAGE.strip_heredoc)
-        `timestamp` was called without specifying an option for `null`. In Rails
-        5.0, this behavior will change to `null: false`. You should manually
-        specify `null: true` to prevent the behavior of your existing migrations
-        from changing.
-        MESSAGE
+        ActiveSupport::Deprecation.warn \
+          "`timestamp` was called without specifying an option for `null`. In Rails " \
+          "5.0, this behavior will change to `null: false`. You should manually " \
+          "specify `null: true` to prevent the behavior of your existing migrations " \
+          "from changing."
       end
     end
 
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/range.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/range.rb
index ae967d5167..84b9490ba3 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/range.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/range.rb
@@ -25,10 +25,10 @@ module ActiveRecord
             if !infinity?(from) && extracted[:exclude_start]
               if from.respond_to?(:succ)
                 from = from.succ
-                ActiveSupport::Deprecation.warn <<-MESSAGE
-Excluding the beginning of a Range is only partialy supported through `#succ`.
-This is not reliable and will be removed in the future.
-                MESSAGE
+                ActiveSupport::Deprecation.warn \
+                  "Excluding the beginning of a Range is only partialy supported " \
+                  "through `#succ`. This is not reliable and will be removed in " \
+                  "the future."
               else
                 raise ArgumentError, "The Ruby Range object does not support excluding the beginning of a Range. (unsupported value: '#{value}')"
               end
diff --git a/activerecord/lib/active_record/reflection.rb b/activerecord/lib/active_record/reflection.rb
index 331b6b0698..c0deb76a33 100644
--- a/activerecord/lib/active_record/reflection.rb
+++ b/activerecord/lib/active_record/reflection.rb
@@ -339,12 +339,13 @@ module ActiveRecord
         return unless scope
 
         if scope.arity > 0
-          ActiveSupport::Deprecation.warn <<-WARNING
-The association scope '#{name}' is instance dependent (the scope block takes an argument).
-Preloading happens before the individual instances are created. This means that there is no instance
-being passed to the association scope. This will most likely result in broken or incorrect behavior.
-Joining, Preloading and eager loading of these associations is deprecated and will be removed in the future.
-          WARNING
+          ActiveSupport::Deprecation.warn \
+            "The association scope '#{name}' is instance dependent (the scope " \
+            "block takes an argument). Preloading happens before the individual " \
+            "instances are created. This means that there is no instance being " \
+            "passed to the association scope. This will most likely result in " \
+            "broken or incorrect behavior. Joining, Preloading and eager loading " \
+            "of these associations is deprecated and will be removed in the future."
         end
       end
       alias :check_eager_loadable! :check_preloadable!
@@ -787,15 +788,13 @@ Joining, Preloading and eager loading of these associations is deprecated and wi
         if names.length > 1
           example_options = options.dup
           example_options[:source] = source_reflection_names.first
-          ActiveSupport::Deprecation.warn <<-eowarn
-Ambiguous source reflection for through association.  Please specify a :source
-directive on your declaration like:
-
-  class #{active_record.name} < ActiveRecord::Base
-    #{macro} :#{name}, #{example_options}
-  end
-
-          eowarn
+          ActiveSupport::Deprecation.warn \
+            "Ambiguous source reflection for through association.  Please " \
+            "specify a :source directive on your declaration like:\n" \
+            "\n" \
+            "  class #{active_record.name} < ActiveRecord::Base\n" \
+            "    #{macro} :#{name}, #{example_options}\n" \
+            "  end"
         end
 
         @source_reflection_name = names.first
diff --git a/activerecord/lib/active_record/relation/query_methods.rb b/activerecord/lib/active_record/relation/query_methods.rb
index 067966321d..e59cce6934 100644
--- a/activerecord/lib/active_record/relation/query_methods.rb
+++ b/activerecord/lib/active_record/relation/query_methods.rb
@@ -94,10 +94,8 @@ module ActiveRecord
     def check_cached_relation # :nodoc:
       if defined?(@arel) && @arel
         @arel = nil
-        ActiveSupport::Deprecation.warn <<-WARNING
-Modifying already cached Relation. The cache will be reset.
-Use a cloned Relation to prevent this warning.
-WARNING
+        ActiveSupport::Deprecation.warn "Modifying already cached Relation. The " \
+          "cache will be reset. Use a cloned Relation to prevent this warning."
       end
     end
 
diff --git a/activerecord/lib/active_record/tasks/database_tasks.rb b/activerecord/lib/active_record/tasks/database_tasks.rb
index 892c78e479..e4164f263e 100644
--- a/activerecord/lib/active_record/tasks/database_tasks.rb
+++ b/activerecord/lib/active_record/tasks/database_tasks.rb
@@ -184,10 +184,10 @@ module ActiveRecord
       end
 
       def load_schema(format = ActiveRecord::Base.schema_format, file = nil)
-        ActiveSupport::Deprecation.warn(<<-MESSAGE.strip_heredoc)
-          This method will act on a specific connection in the future.
-          To act on the current connection, use `load_schema_current` instead.
-        MESSAGE
+        ActiveSupport::Deprecation.warn \
+          "This method will act on a specific connection in the future. " \
+          "To act on the current connection, use `load_schema_current` instead."
+
         load_schema_current(format, file)
       end
 
diff --git a/activerecord/lib/active_record/transactions.rb b/activerecord/lib/active_record/transactions.rb
index 0402384c56..45bc10b9b0 100644
--- a/activerecord/lib/active_record/transactions.rb
+++ b/activerecord/lib/active_record/transactions.rb
@@ -3,16 +3,15 @@ module ActiveRecord
   module Transactions
     extend ActiveSupport::Concern
     ACTIONS = [:create, :destroy, :update]
-    CALLBACK_WARN_MESSAGE = <<-EOF
-Currently, Active Record will rescue any errors raised within
-after_rollback/after_commit callbacks and print them to the logs. In the next
-version, these errors will no longer be rescued. Instead, they will simply
-bubble just like other Active Record callbacks.
-
-You can opt into the new behavior and remove this warning by setting:
-
-    config.active_record.raise_in_transactional_callbacks = true
-EOF
+    CALLBACK_WARN_MESSAGE = "Currently, Active Record suppresses errors raised " \
+      "within `after_rollback`/`after_commit` callbacks and only print them to " \
+      "the logs. In the next version, these errors will no longer be suppressed. " \
+      "Instead, the errors will propagate normally just like in other Active " \
+      "Record callbacks.\n" \
+      "\n" \
+      "You can opt into the new behavior and remove this warning by setting:\n" \
+      "\n" \
+      "  config.active_record.raise_in_transactional_callbacks = true"
 
     included do
       define_callbacks :commit, :rollback,