feat: read matching rules from v3 format

lib/pact/matching_rules/v3/merge.rb

@@ -0,0 +1,112 @@
+require 'pact/array_like'
+require 'pact/matching_rules/jsonpath'
+
+module Pact
+  module MatchingRules
+    module V3
+      class Merge
+
+        def self.call expected, matching_rules, root_path = '$'
+          new(expected, matching_rules, root_path).call
+        end
+
+        def initialize expected, matching_rules, root_path
+          @expected = expected
+          @matching_rules = standardise_paths(matching_rules)
+          @root_path = JsonPath.new(root_path).to_s
+        end
+
+        def call
+          return @expected if @matching_rules.nil? || @matching_rules.empty?
+          recurse @expected, @root_path
+        end
+
+        private
+
+        def standardise_paths matching_rules
+          return matching_rules if matching_rules.nil? || matching_rules.empty?
+          matching_rules.each_with_object({}) do | (path, rule), new_matching_rules |
+            new_matching_rules[JsonPath.new(path).to_s] = rule
+          end
+        end
+
+        def recurse expected, path
+          case expected
+          when Hash then recurse_hash(expected, path)
+          when Array then recurse_array(expected, path)
+          else
+            expected
+          end
+        end
+
+        def recurse_hash hash, path
+          hash.each_with_object({}) do | (k, v), new_hash |
+            new_path = path + "['#{k}']"
+            new_hash[k] = recurse(wrap(v, new_path), new_path)
+          end
+        end
+
+        def recurse_array array, path
+          array_like_children_path = "#{path}[*]*"
+          parent_match_rule = @matching_rules[path] && @matching_rules[path]['matchers'] && @matching_rules[path]['matchers'].first && @matching_rules[path]['matchers'].first['match']
+          children_match_rule = @matching_rules[array_like_children_path] && @matching_rules[array_like_children_path]['matchers'] && @matching_rules[array_like_children_path]['matchers'].first && @matching_rules[array_like_children_path]['matchers'].first['match']
+          min = @matching_rules[path] && @matching_rules[path]['matchers'] && @matching_rules[path]['matchers'].first && @matching_rules[path]['matchers'].first['min']
+
+          if min && (children_match_rule == 'type' || (children_match_rule.nil? && parent_match_rule == 'type'))
+            warn_when_not_one_example_item(array, path)
+            # log_ignored_rules(path, @matching_rules[path], {'min' => min})
+            Pact::ArrayLike.new(recurse(array.first, "#{path}[*]"), min: min)
+          else
+            new_array = []
+            array.each_with_index do | item, index |
+              new_path = path + "[#{index}]"
+              new_array << recurse(wrap(item, new_path), new_path)
+            end
+            new_array
+          end
+        end
+
+        def warn_when_not_one_example_item array, path
+          unless array.size == 1
+            Pact.configuration.error_stream.puts "WARN: Only the first item will be used to match the items in the array at #{path}"
+          end
+        end
+
+        def wrap object, path
+          rules = @matching_rules[path] && @matching_rules[path]['matchers'] && @matching_rules[path]['matchers'].first
+          array_rules = @matching_rules["#{path}[*]*"] && @matching_rules["#{path}[*]*"]['matchers'] && @matching_rules["#{path}[*]*"]['matchers'].first
+          return object unless rules || array_rules
+
+          if rules['match'] == 'type' && !rules.has_key?('min')
+            handle_match_type(object, path, rules)
+          elsif rules['regex']
+            handle_regex(object, path, rules)
+          else
+            log_ignored_rules(path, rules, {})
+            object
+          end
+        end
+
+        def handle_match_type object, path, rules
+          log_ignored_rules(path, rules, {'match' => 'type'})
+          Pact::SomethingLike.new(object)
+        end
+
+        def handle_regex object, path, rules
+          log_ignored_rules(path, rules, {'match' => 'regex', 'regex' => rules['regex']})
+          Pact::Term.new(generate: object, matcher: Regexp.new(rules['regex']))
+        end
+
+        def log_ignored_rules path, rules, used_rules
+          dup_rules = rules.dup
+          used_rules.each_pair do | used_key, used_value |
+            dup_rules.delete(used_key) if dup_rules[used_key] == used_value
+          end
+          if dup_rules.any?
+            $stderr.puts "WARN: Ignoring unsupported matching rules #{dup_rules} for path #{path}"
+          end
+        end
+      end
+    end
+  end
+end

spec/fixtures/pact-v3.json

@@ -0,0 +1,27 @@
+{
+  "consumer": {
+    "name": "Consumer"
+  },
+  "provider": {
+    "name": "Provider"
+  },
+  "messages": [
+    {
+      "contents": {
+        "foo": "bar"
+      },
+      "description": "Published credit data",
+      "metaData": {
+        "contentType": "application/json"
+      },
+      "providerState": "or maybe 'scenario'? not sure about this",
+      "matchingRules": {
+        "body": {
+          "$.foo": {
+            "matchers": [{"match" : "type"}]
+          }
+        }
+      }
+    }
+  ]
+}