Merge pull request #571 from rom-rb/dry-transformer

Switch from transproc to dry-transformer

Author: solnic

changeset/lib/rom/changeset/pipe.rb

@@ -1,15 +1,13 @@
 # frozen_string_literal: true
 
-require 'transproc/transformer'
-
 require 'rom/changeset/pipe_registry'
 
 module ROM
   class Changeset
     # Composable data transformation pipe used by default in changesets
     #
     # @api private
-    class Pipe < Transproc::Transformer[PipeRegistry]
+    class Pipe < Dry::Transformer[PipeRegistry]
       extend Initializer
 
       define!(&:identity)

changeset/lib/rom/changeset/pipe_registry.rb

@@ -1,18 +1,18 @@
 # frozen_string_literal: true
 
-require 'transproc/all'
-require 'transproc/registry'
+require 'dry/transformer/all'
+require 'dry/transformer/registry'
 
 module ROM
   class Changeset
     # Transproc Registry useful for pipe
     #
     # @api private
     module PipeRegistry
-      extend Transproc::Registry
+      extend Dry::Transformer::Registry
 
-      import Transproc::Coercions
-      import Transproc::HashTransformations
+      import Dry::Transformer::Coercions
+      import Dry::Transformer::HashTransformations
 
       def self.add_timestamps(data)
         now = Time.now

changeset/lib/rom/changeset/stateful.rb

@@ -52,9 +52,9 @@ class Stateful < Changeset
       #     end
       #   end
       #
-      # @return [Array<Pipe>, Transproc::Function>]
+      # @return [Array<Pipe>, Dry::Transformer::Function>]
       #
-      # @see https://github.com/solnic/transproc Transproc
+      # @see https://github.com/dry-rb/dry-transformer
       #
       # @api public
       def self.map(**options, &block)
@@ -70,7 +70,7 @@ def self.map(**options, &block)
       # @see Changeset::Stateful.map
       # @see Changeset::Stateful#extend
       #
-      # @return [Array<Pipe>, Transproc::Function>]
+      # @return [Array<Pipe>, Dry::Transformer::Function>]
       #
       # @api public
       def self.extend(*, &block)

changeset/rom-changeset.gemspec

@@ -19,8 +19,8 @@ Gem::Specification.new do |gem|
   }
 
   gem.add_runtime_dependency 'dry-core', '~> 0.4'
+  gem.add_runtime_dependency 'dry-transformer', '~> 0.1'
   gem.add_runtime_dependency 'rom-core', '~> 5.1', '>= 5.1.2'
-  gem.add_runtime_dependency 'transproc', '~> 1.0', '>= 1.1.0'
 
   gem.add_development_dependency 'rake', '~> 11.2'
   gem.add_development_dependency 'rspec', '~> 3.5'

core/lib/rom/core.rb

@@ -10,7 +10,7 @@
 require 'rom/schema_plugin'
 require 'rom/relation'
 require 'rom/mapper'
-require 'rom/processor/transproc'
+require 'rom/processor/transformer'
 require 'rom/commands'
 
 # rom Global

core/lib/rom/mapper.rb

@@ -61,7 +61,7 @@ def self.headers(header)
     # @return [Mapper]
     #
     # @api private
-    def self.build(header = self.header, processor = :transproc)
+    def self.build(header = self.header, processor = :transformer)
       new(header, processor)
     end
 
@@ -74,7 +74,7 @@ def self.registry(descendants)
     end
 
     # @api private
-    def initialize(header, processor = :transproc)
+    def initialize(header, processor = :transformer)
       processor = Mapper.processors.fetch(processor)
       @transformers = self.class.headers(header).map do |hdr|
         processor.build(self, hdr)

core/lib/rom/processor/composer.rb

@@ -0,0 +1,37 @@
+# frozen_string_literal: true
+
+module ROM
+  class Processor
+    # @api private
+    module Composer
+      # @api private
+      class Factory
+        attr_reader :fns, :default
+
+        # @api private
+        def initialize(default = nil)
+          @fns = []
+          @default = default
+        end
+
+        # @api private
+        def <<(other)
+          fns.concat(Array(other).compact)
+          self
+        end
+
+        # @api private
+        def to_fn
+          fns.reduce(:+) || default
+        end
+      end
+
+      # @api private
+      def compose(default = nil)
+        factory = Factory.new(default)
+        yield(factory)
+        factory.to_fn
+      end
+    end
+  end
+end

core/lib/rom/processor/transproc.rb renamed to core/lib/rom/processor/transformer.rb

@@ -1,34 +1,32 @@
 # frozen_string_literal: true
 
-require 'transproc/all'
+require 'dry/transformer/all'
 
 require 'rom/processor'
+require 'rom/processor/composer'
 
 module ROM
   class Processor
-    # Data mapping transformer builder using Transproc
+    # Data mapping transformer builder using dry-transformer
     #
-    # This builds a transproc function that is used to map a whole relation
+    # This builds a transformer object that is used to map a whole relation
     #
-    # @see https://github.com/solnic/transproc too
+    # @see https://github.com/dry-rb/dry-transformer
     #
     # @private
-    class Transproc < Processor
-      include ::Transproc::Composer
+    class Transformer < Processor
+      include Composer
 
       module Functions
-        extend ::Transproc::Registry
+        extend Dry::Transformer::Registry
 
-        import ::Transproc::Coercions
-        import ::Transproc::ArrayTransformations
-        import ::Transproc::HashTransformations
-        import ::Transproc::ClassTransformations
-        import ::Transproc::ProcTransformations
-        INVALID_INJECT_UNION_VALUE = "%s attribute: block is required for :from with union value.".freeze
+        import Dry::Transformer::Coercions
+        import Dry::Transformer::ArrayTransformations
+        import Dry::Transformer::HashTransformations
+        import Dry::Transformer::ClassTransformations
+        import Dry::Transformer::ProcTransformations
 
-        def self.identity(tuple)
-          tuple
-        end
+        INVALID_INJECT_UNION_VALUE = '%s attribute: block is required for :from with union value.'
 
         def self.get(arr, idx)
           arr[idx]
@@ -39,7 +37,7 @@ def self.filter_empty(arr)
         end
 
         def self.inject_union_value(tuple, name, keys, coercer)
-          raise ROM::MapperMisconfiguredError, INVALID_INJECT_UNION_VALUE % [name] if !coercer
+          raise ROM::MapperMisconfiguredError, INVALID_INJECT_UNION_VALUE % [name] unless coercer
 
           values = tuple.values_at(*keys)
           result = coercer.call(*values)
@@ -73,15 +71,15 @@ def self.inject_union_value(tuple, name, keys, coercer)
       # @api private
       attr_reader :row_proc
 
-      # Build a transproc function from the header
+      # Build a transformer object from the header
       #
       # @param [ROM::Header] header
       #
-      # @return [Transproc::Function]
+      # @return [Dry::Transformer::Pipe]
       #
       # @api private
       def self.build(mapper, header)
-        new(mapper, header).to_transproc
+        new(mapper, header).call
       end
 
       # @api private
@@ -93,12 +91,12 @@ def initialize(mapper, header)
         initialize_row_proc
       end
 
-      # Coerce mapper header to a transproc data mapping function
+      # Coerce mapper header to a transformer object
       #
-      # @return [Transproc::Function]
+      # @return [Dry::Transformer::Pipe]
       #
       # @api private
-      def to_transproc
+      def call
         compose(t(:identity)) do |ops|
           combined = header.combined
           ops << t(:combine, combined.map(&method(:combined_args))) if combined.any?
@@ -315,22 +313,22 @@ def visit_fold(attribute, preprocess = false)
       #
       # @api private
       def visit_unfold(attribute, preprocess = false)
-        if preprocess
-          name = attribute.name
-          header = attribute.header
-          keys = attribute.pop_keys
-          key = keys.first
+        return unless preprocess
 
-          others = header.postprocessed
+        name = attribute.name
+        header = attribute.header
+        keys = attribute.pop_keys
+        key = keys.first
 
-          compose do |ops|
-            ops << others.map { |attr|
-              t(:map_array, t(:map_value, name, visit(attr, true)))
-            }
-            ops << t(:map_array, t(:map_value, name, t(:insert_key, key)))
-            ops << t(:map_array, t(:reject_keys, [key] - [name]))
-            ops << t(:ungroup, name, [key])
-          end
+        others = header.postprocessed
+
+        compose do |ops|
+          ops << others.map { |attr|
+            t(:map_array, t(:map_value, name, visit(attr, true)))
+          }
+          ops << t(:map_array, t(:map_value, name, t(:insert_key, key)))
+          ops << t(:map_array, t(:reject_keys, [key] - [name]))
+          ops << t(:ungroup, name, [key])
         end
       end
 

core/lib/rom/transformer.rb

@@ -1,16 +1,15 @@
 # frozen_string_literal: true
 
 require 'dry/core/class_attributes'
-require 'transproc/transformer'
+require 'dry/transformer'
 
-require 'rom/processor/transproc'
+require 'rom/processor/transformer'
 
 module ROM
-  # Transformer is a data mapper which uses Transproc's transformer DSL to define
-  # transformations.
+  # Transformer is a data mapper which uses `Dry::Transformer`'s DSL to define transformations.
   #
   # @api public
-  class Transformer < Transproc::Transformer[ROM::Processor::Transproc::Functions]
+  class Transformer < Dry::Transformer[Processor::Transformer::Functions]
     extend Dry::Core::ClassAttributes
 
     # @!method self.register_as

core/rom-core.gemspec

@@ -28,7 +28,7 @@ Gem::Specification.new do |gem|
   gem.add_runtime_dependency 'dry-types', '~> 1.0'
   gem.add_runtime_dependency 'dry-struct', '~> 1.0'
   gem.add_runtime_dependency 'dry-initializer', '~> 3.0', '>= 3.0.1'
-  gem.add_runtime_dependency 'transproc', '~> 1.0', '>= 1.1.0'
+  gem.add_runtime_dependency 'dry-transformer', '~> 0.1'
 
   gem.add_development_dependency 'rake', '~> 10.3'
   gem.add_development_dependency 'rspec', '~> 3.5'