From 9fa1d29e4feafb4dd712082cf8a27918216740b0 Mon Sep 17 00:00:00 2001
From: Ethan <ethan@unth.net>
Date: Tue, 4 Jan 2022 02:36:49 -0800
Subject: [PATCH] duck-type values responding to #to_hash or #to_ary rather
 than checking class

---
 lib/jsonpath/dig.rb        | 16 +++++++---------
 lib/jsonpath/enumerable.rb | 26 +++++++++++++-------------
 lib/jsonpath/parser.rb     |  4 ++--
 lib/jsonpath/proxy.rb      |  2 +-
 4 files changed, 23 insertions(+), 25 deletions(-)

diff --git a/lib/jsonpath/dig.rb b/lib/jsonpath/dig.rb
index 7a130042..0a25b96f 100644
--- a/lib/jsonpath/dig.rb
+++ b/lib/jsonpath/dig.rb
@@ -20,11 +20,10 @@ def dig_as_hash(context, keys)
 
     # Dig the value of k on context.
     def dig_one(context, k)
-      case context
-      when Hash
-        context[@options[:use_symbols] ? k.to_sym : k]
-      when Array
-        context[k.to_i]
+      if context.respond_to?(:to_hash)
+        context.to_hash[@options[:use_symbols] ? k.to_sym : k]
+      elsif context.respond_to?(:to_ary)
+        context.to_ary[k.to_i]
       else
         if context.respond_to?(:dig)
           context.dig(k)
@@ -37,12 +36,11 @@ def dig_one(context, k)
     # Yields the block if context has a diggable
     # value for k
     def yield_if_diggable(context, k, &blk)
-      case context
-      when Array
+      if context.respond_to?(:to_ary)
         nil
-      when Hash
+      elsif context.respond_to?(:to_hash)
         k = @options[:use_symbols] ? k.to_sym : k
-        return yield if context.key?(k) || @options[:default_path_leaf_to_null]
+        return yield if context.to_hash.key?(k) || @options[:default_path_leaf_to_null]
       else
         if context.respond_to?(:dig)
           digged = dig_one(context, k)
diff --git a/lib/jsonpath/enumerable.rb b/lib/jsonpath/enumerable.rb
index 7a6f2709..76e0b765 100644
--- a/lib/jsonpath/enumerable.rb
+++ b/lib/jsonpath/enumerable.rb
@@ -31,9 +31,10 @@ def each(context = @object, key = nil, pos = 0, &blk)
       end
 
       if pos > 0 && @path[pos - 1] == '..' || (@path[pos - 1] == '*' && @path[pos] != '..')
-        case node
-        when Hash  then node.each { |k, _| each(node, k, pos, &blk) }
-        when Array then node.each_with_index { |_, i| each(node, i, pos, &blk) }
+        if node.respond_to?(:to_hash)
+          node.to_hash.each { |k, _| each(node, k, pos, &blk) }
+        elsif node.respond_to?(:to_ary)
+          node.to_ary.each_with_index { |_, i| each(node, i, pos, &blk) }
         end
       end
     end
@@ -41,11 +42,10 @@ def each(context = @object, key = nil, pos = 0, &blk)
     private
 
     def filter_context(context, keys)
-      case context
-      when Hash
+      if context.respond_to?(:to_hash)
         dig_as_hash(context, keys)
-      when Array
-        context.each_with_object([]) do |c, memo|
+      elsif context.respond_to?(:to_ary)
+        context.to_ary.each_with_object([]) do |c, memo|
           memo << dig_as_hash(c, keys)
         end
       end
@@ -62,7 +62,7 @@ def handle_wildecard(node, expr, _context, _key, pos, &blk)
         when '?'
           handle_question_mark(sub_path, node, pos, &blk)
         else
-          next if node.is_a?(Array) && node.empty?
+          next if node.respond_to?(:to_ary) && node.empty?
           next if node.nil? # when default_path_leaf_to_null is true
 
           array_args = sub_path.split(':')
@@ -103,15 +103,15 @@ def ensure_exclusive_end_index(value)
     end
 
     def handle_question_mark(sub_path, node, pos, &blk)
-      case node
-      when Array
-        node.size.times do |index|
-          @_current_node = node[index]
+      if node.respond_to?(:to_ary)
+        node_ary = node.to_ary
+        node_ary.size.times do |index|
+          @_current_node = node_ary[index]
           if process_function_or_literal(sub_path[1, sub_path.size - 1])
             each(@_current_node, nil, pos + 1, &blk)
           end
         end
-      when Hash
+      elsif node.respond_to?(:to_hash)
         if process_function_or_literal(sub_path[1, sub_path.size - 1])
           each(@_current_node, nil, pos + 1, &blk)
         end
diff --git a/lib/jsonpath/parser.rb b/lib/jsonpath/parser.rb
index 79feb8c9..475f53f6 100644
--- a/lib/jsonpath/parser.rb
+++ b/lib/jsonpath/parser.rb
@@ -58,7 +58,7 @@ def parse_exp(exp)
         next if i.empty?
 
         index = Integer(i[0])
-        raise ArgumentError, 'Node does not appear to be an array.' unless @_current_node.is_a?(Array)
+        raise ArgumentError, 'Node does not appear to be an array.' unless @_current_node.respond_to?(:to_ary)
         raise ArgumentError, "Index out of bounds for nested array. Index: #{index}" if @_current_node.size < index
 
         @_current_node = @_current_node[index]
@@ -93,7 +93,7 @@ def parse_exp(exp)
 
       el = if elements.empty?
              @_current_node
-           elsif @_current_node.is_a?(Hash)
+           elsif @_current_node.respond_to?(:to_hash)
              dig(@_current_node, *elements)
            else
              elements.inject(@_current_node, &:__send__)
diff --git a/lib/jsonpath/proxy.rb b/lib/jsonpath/proxy.rb
index 3d11a8b3..8bc34b4b 100644
--- a/lib/jsonpath/proxy.rb
+++ b/lib/jsonpath/proxy.rb
@@ -52,7 +52,7 @@ def _delete(obj, path)
 
     def _remove(obj)
       obj.each do |o|
-        if o.is_a?(Hash) || o.is_a?(Array)
+        if o.respond_to?(:to_hash) || o.respond_to?(:to_ary)
           _remove(o)
           o.delete({})
         end