Class: CouchPotato::RSpec::MapReduceToMatcher

Inherits:
Object
  • Object
show all
Defined in:
lib/couch_potato/rspec/matchers/map_reduce_to_matcher.rb

Instance Method Summary collapse

Constructor Details

#initialize(expected_ruby, input_ruby, options) ⇒ MapReduceToMatcher

Returns a new instance of MapReduceToMatcher.



21
22
23
24
25
# File 'lib/couch_potato/rspec/matchers/map_reduce_to_matcher.rb', line 21

def initialize(expected_ruby, input_ruby, options)
  @expected_ruby = expected_ruby
  @input_ruby = input_ruby
  @options = options
end

Instance Method Details

#failure_messageObject



193
194
195
# File 'lib/couch_potato/rspec/matchers/map_reduce_to_matcher.rb', line 193

def failure_message
  "Expected to map/reduce to #{@expected_ruby.inspect} but got #{@actual_ruby.inspect}."
end

#failure_message_when_negatedObject



197
198
199
# File 'lib/couch_potato/rspec/matchers/map_reduce_to_matcher.rb', line 197

def failure_message_when_negated
  "Expected not to map/reduce to #{@actual_ruby.inspect} but did."
end

#matches?(view_spec) ⇒ Boolean

Returns:

  • (Boolean)


27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
# File 'lib/couch_potato/rspec/matchers/map_reduce_to_matcher.rb', line 27

def matches?(view_spec)
  js = <<-JS
    (function() {
      var sum = function(values) {
        return values.reduce(function(memo, value) { return memo + value; });
      };
      // Equivalents of couchdb built-in reduce functions whose names can be
      // given as the reduce function in the view_spec:
      var _sum = function(keys, values, rereduce) {
        return sum(values);
      }
      var _count = function(keys, values, rereduce) {
        if (rereduce) {
          return sum(values);
        } else {
          return values.length;
        }
      }
      var _stats = function(keys, values, rereduce) {
        var result = {sum: 0, count: 0, min: Number.MAX_VALUE, max: Number.MIN_VALUE, sumsqr: 0};
        if (rereduce) {
          for (var i in values) {
            var value = values[i];
            result.sum += value.sum;
            result.count += value.count;
            result.min = Math.min(result.min, value.min);
            result.max = Math.max(result.max, value.max);
            result.sumsqr += value.sumsqr;
          }
        } else {
          for (var i in values) {
            var value = values[i];
            result.sum += value;
            result.count += 1;
            result.min = Math.min(result.min, value);
            result.max = Math.max(result.max, value);
            result.sumsqr += Math.pow(value, 2);
          }
        }
        return result;
      }

      var docs = #{@input_ruby.to_json};
      var options = #{@options.to_json};
      var map = #{view_spec.map_function};
      var reduce = #{view_spec.reduce_function};
      var lib = #{view_spec.respond_to?(:lib) && view_spec.lib.to_json};
      var collate = (function() { var module = {exports: {}}; var exports = module.exports; eval(#{File.read(File.expand_path(File.dirname(__FILE__) + '/../../../../vendor/pouchdb-collate/pouchdb-collate.js')).to_json}); return module.exports.collate;})();

      // Map the input docs
      var require = function(modulePath) {
        var module = {exports: {}};
        var exports = module.exports;
        var pathArray = modulePath.split("/").slice(2);
        var result = lib;
        for (var i in pathArray) {
          result = result[pathArray[i]];
        }
        eval(result);
        return module.exports;
      }

      var unfilteredMapResults = [];
      var emit = function(key, value) {
        unfilteredMapResults.push({key: key, value: value});
      };
      for (var i in docs) {
        map(docs[i]);
      }

      // Filter results by key/keys/startkey/endkey (if given).
      var mapResults = [];
      if (options.key) {
        for (var r in unfilteredMapResults) {
          var result = unfilteredMapResults[r];
          if (collate(result.key, options.key) == 0)
            mapResults.push(result);
        }
      }
      // couchdb does not support multiple keys for reduce views without group=true
      else if (options.keys && options.group) {
        for (var r in unfilteredMapResults) {
          var result = unfilteredMapResults[r];
          for (var k in options.keys) {
            var key = options.keys[k];
            if (collate(result.key, key) == 0) {
              mapResults.push(result);
              break;
            }
          }
        }
      }
      else if (options.startkey || options.endkey) {
        for (var r in unfilteredMapResults) {
          var result = unfilteredMapResults[r];
          if (options.startkey && collate(options.startkey, result.key) > 0)
            continue;
          if (options.endkey && collate(result.key, options.endkey) > 0)
            continue;
          mapResults.push(result);
        }
      }
      else {
        mapResults = unfilteredMapResults;
      }

      // Group the map results, honoring the group and group_level options
      var grouped = [];
      if (options.group || options.group_level) {
        var groupLevel = options.group_level;
        if (groupLevel == "exact" || options.group == true)
          groupLevel = 9999;

        for (var mr in mapResults) {
          var mapResult = mapResults[mr];
          var groupedKey = Array.isArray(mapResult.key) ? mapResult.key.slice(0, groupLevel) : mapResult.key;
          var groupFound = false;
          for (var g in grouped) {
            var group = grouped[g];
            if (collate(groupedKey, group.groupedKey) == 0) {
              group.keys.push(mapResult.key);
              group.values.push(mapResult.value);
              groupFound = true;
              break;
            }
          }

          if (!groupFound)
            grouped.push({keys: [mapResult.key], groupedKey: groupedKey, values: [mapResult.value]});
        }
      } else {
        var group = {keys: null, groupedKey: null, values: []};
        for (var mr in mapResults)
          group.values.push(mapResults[mr].value);
        grouped.push(group);
      }

      // Reduce the grouped map results
      var results = [];
      for (var g in grouped) {
        var group = grouped[g], reduced = null;
        if (group.values.length >= 2) {
          // Split the values into two parts, reduce each part, then rereduce those results
          var mid = parseInt(group.values.length / 2);
          var keys1 = (group.keys || []).slice(0, mid),
              values1 = group.values.slice(0, mid);
          var reduced1 = reduce(keys1, values1, false);
          var keys2 = (group.keys || []).slice(mid, group.values.length),
              values2 = group.values.slice(mid, group.values.length);
          var reduced2 = reduce(keys2, values2, false);
          reduced = reduce(null, [reduced1, reduced2], true);
        } else {
          // Not enough values to split, so just reduce, and then rereduce the single result
          reduced = reduce(group.keys, group.values, false);
          reduced = reduce(null, [reduced], true);
        }
        results.push({key: group.groupedKey, value: reduced});
      }

      return JSON.stringify(results);
    })()
  JS
  @actual_ruby = JSON.parse(ExecJS.eval(js))
  @expected_ruby == @actual_ruby
end