Reorganize codebase (#230)

In attempting to detail the architecture of this codebase, I realized
that it would be easier if the parts of SuperDiff that implemented
differs, inspection tree builders, operation tree builders, operation
tree flatteners, and operation trees for Ruby objects were split off
into their own directory. To that end, alongside RSpec, ActiveRecord,
and ActiveSupport, there is now a "Basic" feature module. In addition,
to make the file structure a little flatter, I've also renamed
`InspectionTreeBuilders` in various feature modules up one level (so,
`ObjectInspection::InspectionTreeBuilders` is now simply
`InspectionTreeBuilders`).

Following this change, SuperDiff can now be divided into 4 layers (here
I'm putting CSI in brackets because it's not a public module):

```
          ----------------- [SuperDiff::CSI]
        /                     /     |
       /           SuperDiff::Core ----------------------
      |              /    |     \   |                    \
      |       /^^^^^^     |  SuperDiff::Basic             \
      |      /            |   /     |     \                \
      |     | /^^^^^^^^^^^|^^^^     |      ^^^^^^^^^^^^^\   \
SuperDiff::RSpec         SuperDiff::ActiveRecord     SuperDiff::ActiveSupport
```

Here is a full list of renames:

- The following constants that were previously available under
`SuperDiff` are now located under `SuperDiff::Core`:
  - `ColorizedDocumentExtensions`
  - `Configuration`
  - `GemVersion`
  - `Helpers`
  - `ImplementationChecks`
  - `Line`
  - `RecursionGuard`
  - `TieredLines`
  - `TieredLinesElider`
  - `TieredLinesFormatter`
- Everything under `SuperDiff::Differs` is now under
`SuperDiff::Basic::Differs`
- All error classes under `SuperDiff::Errors` have been moved out and
are now directly under `SuperDiff::Core`
- `SuperDiff::ObjectInspection::InspectionTree` is now
`SuperDiff::Core::InspectionTree`
- Everything under `SuperDiff::ObjectInspection::InspectionTreeBuilders`
is now under `SuperDiff::Core::InspectionTreeBuilders`
- Everything under `SuperDiff::ObjectInspection::Nodes` is now under
`SuperDiff::Core::InspectionTreeNodes`
- Everything under `SuperDiff::OperationTreeBuilders` is now under
`SuperDiff::Basic::OperationTreeBuilders`
- Everything under `SuperDiff::OperationTreeFlatteners` is now under
`SuperDiff::Basic::OperationTreeFlatteners`
- Everything under `SuperDiff::OperationTrees` is now under
`SuperDiff::Basic::OperationTrees`
- Everything under `SuperDiff::Operations` has been moved out and is now
directly under `SuperDiff::Core`
- Everything under
`SuperDiff::ActiveRecord::ObjectInspection::InspectionTreeBuilders` is
now under `SuperDiff::ActiveRecord::InspectionTreeBuilders`
- Everything under
`SuperDiff::ActiveSupport::ObjectInspection::InspectionTreeBuilders` is
now under `SuperDiff::ActiveSupport::InspectionTreeBuilders`
- Everything under
`SuperDiff::RSpec::ObjectInspection::InspectionTreeBuilders` is now
under `SuperDiff::RSpec::InspectionTreeBuilders`

To maintain backward compatibility, I've left all of the original
constants in place, but they will now print deprecation warnings when
used. I will remove them in 1.0.0.

Author: mcmire

lib/super_diff.rb

@@ -1,47 +1,93 @@
 require "attr_extras/explicit"
-require "diff-lcs"
-require "patience_diff"
 require "date"
 
 module SuperDiff
-  autoload(
-    :ColorizedDocumentExtensions,
-    "super_diff/colorized_document_extensions"
-  )
-  autoload :OperationTreeFlatteners, "super_diff/operation_tree_flatteners"
-  autoload :Configuration, "super_diff/configuration"
+  autoload :Core, "super_diff/core"
   autoload :Csi, "super_diff/csi"
-  autoload :DiffFormatters, "super_diff/diff_formatters"
   autoload :Differs, "super_diff/differs"
   autoload :EqualityMatchers, "super_diff/equality_matchers"
   autoload :Errors, "super_diff/errors"
-  autoload :GemVersion, "super_diff/gem_version"
-  autoload :Helpers, "super_diff/helpers"
-  autoload :ImplementationChecks, "super_diff/implementation_checks"
-  autoload :Line, "super_diff/line"
-  autoload :TieredLines, "super_diff/tiered_lines"
-  autoload :TieredLinesElider, "super_diff/tiered_lines_elider"
-  autoload :TieredLinesFormatter, "super_diff/tiered_lines_formatter"
   autoload :ObjectInspection, "super_diff/object_inspection"
-  autoload :OperationTrees, "super_diff/operation_trees"
   autoload :OperationTreeBuilders, "super_diff/operation_tree_builders"
+  autoload :OperationTreeFlatteners, "super_diff/operation_tree_flatteners"
+  autoload :OperationTrees, "super_diff/operation_trees"
   autoload :Operations, "super_diff/operations"
-  autoload :RecursionGuard, "super_diff/recursion_guard"
   autoload :VERSION, "super_diff/version"
 
+  def self.const_missing(missing_const_name)
+    if Core.const_defined?(missing_const_name)
+      warn <<~EOT
+        WARNING: SuperDiff::#{missing_const_name} is deprecated and will be removed in the next major release.
+        Please use SuperDiff::Core::#{missing_const_name} instead.
+        #{caller_locations.join("\n")}
+      EOT
+      Core.const_get(missing_const_name)
+    elsif Basic.const_defined?(missing_const_name)
+      warn <<~EOT
+        WARNING: SuperDiff::#{missing_const_name} is deprecated and will be removed in the next major release.
+        Please use SuperDiff::Basic::#{missing_const_name} instead.
+        #{caller_locations.join("\n")}
+      EOT
+      Basic.const_get(missing_const_name)
+    else
+      super
+    end
+  end
+
   def self.configure
     yield configuration
     configuration.updated
   end
 
   def self.configuration
-    @_configuration ||= Configuration.new
+    @_configuration ||= Core::Configuration.new
+  end
+
+  def self.diff(
+    expected,
+    actual,
+    indent_level: 0,
+    raise_if_nothing_applies: true
+  )
+    Core::DifferDispatcher.call(
+      expected,
+      actual,
+      available_classes: configuration.extra_differ_classes,
+      indent_level: indent_level,
+      raise_if_nothing_applies: raise_if_nothing_applies
+    )
+  end
+
+  def self.build_operation_tree_for(
+    expected,
+    actual,
+    extra_operation_tree_builder_classes: [],
+    raise_if_nothing_applies: false
+  )
+    Core::OperationTreeBuilderDispatcher.call(
+      expected,
+      actual,
+      available_classes:
+        configuration.extra_operation_tree_builder_classes +
+          extra_operation_tree_builder_classes,
+      raise_if_nothing_applies: raise_if_nothing_applies
+    )
+  end
+
+  def self.find_operation_tree_for(value)
+    SuperDiff::Core::OperationTreeFinder.call(
+      value,
+      available_classes: configuration.extra_operation_tree_classes
+    )
   end
 
   def self.inspect_object(object, as_lines:, **rest)
-    SuperDiff::RecursionGuard.guarding_recursion_of(object) do
+    Core::RecursionGuard.guarding_recursion_of(object) do
       inspection_tree =
-        ObjectInspection::InspectionTreeBuilders::Main.call(object)
+        Core::InspectionTreeBuilderDispatcher.call(
+          object,
+          available_classes: configuration.extra_inspection_tree_builder_classes
+        )
 
       if as_lines
         inspection_tree.render_to_lines(object, **rest)
@@ -87,3 +133,5 @@ def self.insert_singleton_overrides(target_module, mod = nil, &block)
     end
   end
 end
+
+require "super_diff/basic"

lib/super_diff/active_record.rb

@@ -1,28 +1,24 @@
 require "super_diff/active_support"
 
+require "super_diff/active_record/differs"
+require "super_diff/active_record/inspection_tree_builders"
+require "super_diff/active_record/operation_trees"
+require "super_diff/active_record/operation_tree_builders"
+require "super_diff/active_record/operation_tree_flatteners"
+
 module SuperDiff
   module ActiveRecord
-    autoload :Differs, "super_diff/active_record/differs"
-    autoload(:ObjectInspection, "super_diff/active_record/object_inspection")
-    autoload(:OperationTrees, "super_diff/active_record/operation_trees")
-    autoload(
-      :OperationTreeBuilders,
-      "super_diff/active_record/operation_tree_builders"
-    )
-    autoload(
-      :OperationTreeFlatteners,
-      "super_diff/active_record/operation_tree_flatteners"
-    )
+    autoload :ObjectInspection, "super_diff/active_record/object_inspection"
 
     SuperDiff.configure do |config|
-      config.add_extra_differ_classes(Differs::ActiveRecordRelation)
-      config.add_extra_operation_tree_builder_classes(
+      config.prepend_extra_differ_classes(Differs::ActiveRecordRelation)
+      config.prepend_extra_operation_tree_builder_classes(
         OperationTreeBuilders::ActiveRecordModel,
         OperationTreeBuilders::ActiveRecordRelation
       )
-      config.add_extra_inspection_tree_builder_classes(
-        ObjectInspection::InspectionTreeBuilders::ActiveRecordModel,
-        ObjectInspection::InspectionTreeBuilders::ActiveRecordRelation
+      config.prepend_extra_inspection_tree_builder_classes(
+        InspectionTreeBuilders::ActiveRecordModel,
+        InspectionTreeBuilders::ActiveRecordRelation
       )
     end
   end

lib/super_diff/active_record/differs/active_record_relation.rb

@@ -1,7 +1,7 @@
 module SuperDiff
   module ActiveRecord
     module Differs
-      class ActiveRecordRelation < SuperDiff::Differs::Base
+      class ActiveRecordRelation < Core::AbstractDiffer
         def self.applies_to?(expected, actual)
           expected.is_a?(::Array) && actual.is_a?(::ActiveRecord::Relation)
         end

lib/super_diff/active_record/inspection_tree_builders.rb

@@ -0,0 +1,14 @@
+module SuperDiff
+  module ActiveRecord
+    module InspectionTreeBuilders
+      autoload(
+        :ActiveRecordModel,
+        "super_diff/active_record/inspection_tree_builders/active_record_model"
+      )
+      autoload(
+        :ActiveRecordRelation,
+        "super_diff/active_record/inspection_tree_builders/active_record_relation"
+      )
+    end
+  end
+end

lib/super_diff/active_record/inspection_tree_builders/active_record_model.rb

@@ -0,0 +1,49 @@
+module SuperDiff
+  module ActiveRecord
+    module InspectionTreeBuilders
+      class ActiveRecordModel < Core::AbstractInspectionTreeBuilder
+        def self.applies_to?(value)
+          value.is_a?(::ActiveRecord::Base)
+        end
+
+        def call
+          Core::InspectionTree.new do |t1|
+            t1.as_lines_when_rendering_to_lines(
+              collection_bookend: :open
+            ) do |t2|
+              t2.add_text "#<#{object.class} "
+
+              # stree-ignore
+              t2.when_rendering_to_lines do |t3|
+                  t3.add_text "{"
+                end
+            end
+
+            t1.nested do |t2|
+              t2.insert_separated_list(
+                ["id"] + (object.attributes.keys.sort - ["id"])
+              ) do |t3, name|
+                t3.as_prefix_when_rendering_to_lines do |t4|
+                  t4.add_text "#{name}: "
+                end
+
+                t3.add_inspection_of object.read_attribute(name)
+              end
+            end
+
+            t1.as_lines_when_rendering_to_lines(
+              collection_bookend: :close
+            ) do |t2|
+              # stree-ignore
+              t2.when_rendering_to_lines do |t3|
+                  t3.add_text "}"
+                end
+
+              t2.add_text ">"
+            end
+          end
+        end
+      end
+    end
+  end
+end

lib/super_diff/active_record/inspection_tree_builders/active_record_relation.rb

@@ -0,0 +1,34 @@
+module SuperDiff
+  module ActiveRecord
+    module InspectionTreeBuilders
+      class ActiveRecordRelation < Core::AbstractInspectionTreeBuilder
+        def self.applies_to?(value)
+          value.is_a?(::ActiveRecord::Relation)
+        end
+
+        def call
+          Core::InspectionTree.new do |t1|
+            # stree-ignore
+            t1.as_lines_when_rendering_to_lines(
+                collection_bookend: :open
+              ) do |t2|
+                t2.add_text "#<ActiveRecord::Relation ["
+              end
+
+            # stree-ignore
+            t1.nested do |t2|
+                t2.insert_array_inspection_of(object)
+              end
+
+            # stree-ignore
+            t1.as_lines_when_rendering_to_lines(
+                collection_bookend: :close
+              ) do |t2|
+                t2.add_text "]>"
+              end
+          end
+        end
+      end
+    end
+  end
+end

lib/super_diff/active_record/monkey_patches.rb

@@ -1,5 +1,6 @@
 # rubocop:disable Style/BracesAroundHashParameters, Style/ClassAndModuleChildren
 class ActiveRecord::Base
+  # TODO: Remove this monkey patch if possible
   def attributes_for_super_diff
     (attributes.keys.sort - ["id"]).reduce({ id: id }) do |hash, key|
       hash.merge(key.to_sym => attributes[key])

lib/super_diff/active_record/object_inspection.rb

@@ -1,10 +1,22 @@
 module SuperDiff
   module ActiveRecord
     module ObjectInspection
-      autoload(
-        :InspectionTreeBuilders,
-        "super_diff/active_record/object_inspection/inspection_tree_builders"
-      )
+      module InspectionTreeBuilders
+        def self.const_missing(missing_const_name)
+          if ActiveRecord::InspectionTreeBuilders.const_defined?(
+               missing_const_name
+             )
+            warn <<~EOT
+              WARNING: SuperDiff::ActiveRecord::ObjectInspection::InspectionTreeBuilders::#{missing_const_name} is deprecated and will be removed in the next major release.
+              Please use SuperDiff::ActiveRecord::InspectionTreeBuilders::#{missing_const_name} instead.
+              #{caller_locations.join("\n")}
+            EOT
+            ActiveRecord::InspectionTreeBuilders.const_get(missing_const_name)
+          else
+            super
+          end
+        end
+      end
     end
   end
 end