Add tests

test/run.js

@@ -32,6 +32,7 @@ var tests = [
   require('./view/population.js'),
   require('./view/population_only_function.js'),
   require('./view/sort_distance.js'),
+  require('./view/sort_popularity.js'),
   require('./view/sources.js'),
   require('./view/boundary_gid.js'),
   require('./view/leaf/match.js'),

test/view/sort_popularity.js

@@ -0,0 +1,68 @@
+var sort_popularity = require('../../view/sort_popularity');
+var VariableStore = require('../../lib/VariableStore');
+
+function getBaseVariableStore(toExclude) {
+  var vs = new VariableStore();
+  vs.var('sort:field', 'popularity');
+
+  if (toExclude) {
+    vs.unset(toExclude);
+  }
+
+  return vs;
+
+}
+
+module.exports.tests = {};
+
+module.exports.tests.interface = function(test, common) {
+  test('interface: contructor', function(t) {
+    t.equal(typeof sort_popularity, 'function', 'valid function');
+    t.equal(sort_popularity.length, 1, 'takes 1 arg');
+    t.end();
+  });
+
+};
+
+module.exports.tests.missing_variable_conditions = function(test, common) {
+  var variables = Object.keys(getBaseVariableStore().export());
+
+  variables.forEach(function(missing_variable) {
+    test('missing required variable ' + missing_variable + ' should return null', function(t) {
+      var vs = getBaseVariableStore(missing_variable);
+
+      t.equal(sort_popularity(vs), null, 'should have returned null for unset ' + missing_variable);
+      t.end();
+
+    });
+  });
+
+};
+
+module.exports.tests.no_exceptions_conditions = function(test, common) {
+  test('all properties set should return valid object', function(t) {
+    var vs = getBaseVariableStore();
+
+    var actual = sort_popularity(vs);
+
+    var expected = {
+      popularity: {
+        order: 'desc'
+      }
+    };
+
+    t.deepEquals(actual, expected, 'should have returned object');
+    t.end();
+
+  });
+
+};
+
+module.exports.all = function (tape, common) {
+  function test(name, testFunction) {
+    return tape('sort_popularity ' + name, testFunction);
+  }
+  for( var testCase in module.exports.tests ){
+    module.exports.tests[testCase](test, common);
+  }
+};