Merge pull request #78 from ruby-syntax-tree/use-prettier-print

Use prettier_print

Author: kddnewton

Gemfile

@@ -3,5 +3,3 @@
 source "https://rubygems.org"
 
 gemspec
-
-gem "rubocop"

Gemfile.lock

@@ -2,6 +2,7 @@ PATH
   remote: .
   specs:
     syntax_tree (2.4.1)
+      prettier_print
 
 GEM
   remote: https://rubygems.org/
@@ -12,6 +13,7 @@ GEM
     parallel (1.22.1)
     parser (3.1.2.0)
       ast (~> 2.4.1)
+    prettier_print (0.1.0)
     rainbow (3.1.1)
     rake (13.0.6)
     regexp_parser (2.4.0)

lib/syntax_tree.rb

@@ -2,7 +2,7 @@
 
 require "json"
 require "pp"
-require "prettyprint"
+require "prettier_print"
 require "ripper"
 require "stringio"
 
@@ -16,30 +16,6 @@
 require_relative "syntax_tree/visitor/match_visitor"
 require_relative "syntax_tree/visitor/pretty_print_visitor"
 
-# If PrettyPrint::Align isn't defined, then we haven't gotten the updated
-# version of prettyprint. In that case we'll define our own. This is going to
-# overwrite a bunch of methods, so silencing them as well.
-unless PrettyPrint.const_defined?(:Align)
-  verbose = $VERBOSE
-  $VERBOSE = nil
-
-  begin
-    require_relative "syntax_tree/prettyprint"
-  ensure
-    $VERBOSE = verbose
-  end
-end
-
-# When PP is running, it expects that everything that interacts with it is going
-# to flow through PP.pp, since that's the main entry into the module from the
-# perspective of its uses in core Ruby. In doing so, it calls guard_inspect_key
-# at the top of the PP.pp method, which establishes some thread-local hashes to
-# check for cycles in the pretty printed tree. This means that if you want to
-# manually call pp on some object _before_ you have established these hashes,
-# you're going to break everything. So this call ensures that those hashes have
-# been set up before anything uses pp manually.
-PP.new(+"", 0).guard_inspect_key {}
-
 # Syntax Tree is a suite of tools built on top of the internal CRuby parser. It
 # provides the ability to generate a syntax tree from source, as well as the
 # tools necessary to inspect and manipulate that syntax tree. It can be used to

lib/syntax_tree/formatter.rb

@@ -3,7 +3,7 @@
 module SyntaxTree
   # A slightly enhanced PP that knows how to format recursively including
   # comments.
-  class Formatter < PP
+  class Formatter < PrettierPrint
     COMMENT_PRIORITY = 1
     HEREDOC_PRIORITY = 2
 

lib/syntax_tree/node.rb

@@ -123,7 +123,7 @@ def to_json(*opts)
     end
 
     def construct_keys
-      PP.format(+"") { |q| Visitor::MatchVisitor.new(q).visit(self) }
+      PrettierPrint.format(+"") { |q| Visitor::MatchVisitor.new(q).visit(self) }
     end
   end
 
@@ -1666,52 +1666,6 @@ def format(q)
     end
   end
 
-  # This module will remove any breakables from the list of contents so that no
-  # newlines are present in the output.
-  module RemoveBreaks
-    class << self
-      def call(doc)
-        marker = Object.new
-        stack = [doc]
-
-        while stack.any?
-          doc = stack.pop
-
-          if doc == marker
-            stack.pop
-            next
-          end
-
-          stack += [doc, marker]
-
-          case doc
-          when PrettyPrint::Align, PrettyPrint::Indent, PrettyPrint::Group
-            doc.contents.map! { |child| remove_breaks(child) }
-            stack += doc.contents.reverse
-          when PrettyPrint::IfBreak
-            doc.flat_contents.map! { |child| remove_breaks(child) }
-            stack += doc.flat_contents.reverse
-          end
-        end
-      end
-
-      private
-
-      def remove_breaks(doc)
-        case doc
-        when PrettyPrint::Breakable
-          text = PrettyPrint::Text.new
-          text.add(object: doc.force? ? "; " : doc.separator, width: doc.width)
-          text
-        when PrettyPrint::IfBreak
-          PrettyPrint::Align.new(indent: 0, contents: doc.flat_contents)
-        else
-          doc
-        end
-      end
-    end
-  end
-
   # BlockVar represents the parameters being declared for a block. Effectively
   # this node is everything contained within the pipes. This includes all of the
   # various parameter types, as well as block-local variable declarations.
@@ -1752,8 +1706,7 @@ def deconstruct_keys(_keys)
 
     def format(q)
       q.group(0, "|", "|") do
-        doc = q.format(params)
-        RemoveBreaks.call(doc)
+        q.remove_breaks(q.format(params))
 
         if locals.any?
           q.text("; ")
@@ -3096,31 +3049,6 @@ def format(q)
 
     private
 
-    # This is a somewhat naive method that is attempting to sum up the width of
-    # the doc nodes that make up the given doc node. This is used to align
-    # content.
-    def doc_width(parent)
-      queue = [parent]
-      width = 0
-
-      until queue.empty?
-        doc = queue.shift
-
-        case doc
-        when PrettyPrint::Text
-          width += doc.width
-        when PrettyPrint::Indent, PrettyPrint::Align, PrettyPrint::Group
-          queue = doc.contents + queue
-        when PrettyPrint::IfBreak
-          queue = doc.break_contents + queue
-        when PrettyPrint::Breakable
-          width = 0
-        end
-      end
-
-      width
-    end
-
     def argument_alignment(q, doc)
       # Very special handling case for rspec matchers. In general with rspec
       # matchers you expect to see something like:
@@ -3138,7 +3066,7 @@ def argument_alignment(q, doc)
       if %w[to not_to to_not].include?(message.value)
         0
       else
-        width = doc_width(doc) + 1
+        width = q.last_position(doc) + 1
         width > (q.maxwidth / 2) ? 0 : width
       end
     end
@@ -4891,17 +4819,9 @@ def deconstruct_keys(_keys)
     end
 
     def format(q)
-      # This is a very specific behavior that should probably be included in the
-      # prettyprint module. It's when you want to force a newline, but don't
-      # want to force the break parent.
-      breakable = -> do
-        q.target << PrettyPrint::Breakable.new(
-          " ",
-          1,
-          indent: false,
-          force: true
-        )
-      end
+      # This is a very specific behavior where you want to force a newline, but
+      # don't want to force the break parent.
+      breakable = -> { q.breakable(indent: false, force: :skip_break_parent) }
 
       q.group do
         q.format(beginning)
@@ -5325,9 +5245,8 @@ def format_ternary(q)
                 # force it into the output but we _don't_ want to explicitly
                 # break the parent. If a break-parent shows up in the tree, then
                 # it's going to force it all the way up to the tree, which is
-                # going to negate the ternary. Maybe this should be an option in
-                # prettyprint? As in force: :no_break_parent or something.
-                q.target << PrettyPrint::Breakable.new(" ", 1, force: true)
+                # going to negate the ternary.
+                q.breakable(force: :skip_break_parent)
                 q.format(node.consequent.statements)
               end
             end
@@ -8314,8 +8233,7 @@ def format(q)
         # same line in the source, then we're going to leave them in place and
         # assume that's the way the developer wanted this expression
         # represented.
-        doc = q.group(0, '#{', "}") { q.format(statements) }
-        RemoveBreaks.call(doc)
+        q.remove_breaks(q.group(0, '#{', "}") { q.format(statements) })
       else
         q.group do
           q.text('#{')