diff --git a/test/unit/helper/geojsonify_place_details.js b/test/unit/helper/geojsonify_place_details.js
new file mode 100644
index 00000000..3bc96adc
--- /dev/null
+++ b/test/unit/helper/geojsonify_place_details.js
@@ -0,0 +1,537 @@
+const geojsonify = require('../../../helper/geojsonify_place_details');
+
+module.exports.tests = {};
+
+module.exports.tests.geojsonify_place_details = (test, common) => {
+  test('plain old string values should be copied verbatim, replacing old values', t => {
+    const source = {
+      unknown_field: 'original unknown_field value',
+      housenumber: 'housenumber value',
+      street: 'street value',
+      postalcode: 'postalcode value',
+      postalcode_gid: 'postalcode_gid value',
+      match_type: 'match_type value',
+      accuracy: 'accuracy value',
+      country: 'country value',
+      country_gid: 'country_gid value',
+      country_a: 'country_a value',
+      dependency: 'dependency value',
+      dependency_gid: 'dependency_gid value',
+      dependency_a: 'dependency_a value',
+      macroregion: 'macroregion value',
+      macroregion_gid: 'macroregion_gid value',
+      macroregion_a: 'macroregion_a value',
+      region: 'region value',
+      region_gid: 'region_gid value',
+      region_a: 'region_a value',
+      macrocounty: 'macrocounty value',
+      macrocounty_gid: 'macrocounty_gid value',
+      macrocounty_a: 'macrocounty_a value',
+      county: 'county value',
+      county_gid: 'county_gid value',
+      county_a: 'county_a value',
+      localadmin: 'localadmin value',
+      localadmin_gid: 'localadmin_gid value',
+      localadmin_a: 'localadmin_a value',
+      locality: 'locality value',
+      locality_gid: 'locality_gid value',
+      locality_a: 'locality_a value',
+      borough: 'borough value',
+      borough_gid: 'borough_gid value',
+      borough_a: 'borough_a value',
+      neighbourhood: 'neighbourhood value',
+      neighbourhood_gid: 'neighbourhood_gid value',
+      label: 'label value'
+    };
+    const destination = {
+      unknown_field: 'original unknown_field value',
+      housenumber: 'original housenumber value',
+      street: 'original street value',
+      postalcode: 'original postalcode value',
+      postalcode_gid: 'original postalcode_gid value',
+      match_type: 'original match_type value',
+      accuracy: 'original accuracy value',
+      country: 'original country value',
+      country_gid: 'original country_gid value',
+      country_a: 'original country_a value',
+      dependency: 'original dependency value',
+      dependency_gid: 'original dependency_gid value',
+      dependency_a: 'original dependency_a value',
+      macroregion: 'original macroregion value',
+      macroregion_gid: 'original macroregion_gid value',
+      macroregion_a: 'original macroregion_a value',
+      region: 'original region value',
+      region_gid: 'original region_gid value',
+      region_a: 'original region_a value',
+      macrocounty: 'original macrocounty value',
+      macrocounty_gid: 'original macrocounty_gid value',
+      macrocounty_a: 'original macrocounty_a value',
+      county: 'original county value',
+      county_gid: 'original county_gid value',
+      county_a: 'original county_a value',
+      localadmin: 'original localadmin value',
+      localadmin_gid: 'original localadmin_gid value',
+      localadmin_a: 'original localadmin_a value',
+      locality: 'original locality value',
+      locality_gid: 'original locality_gid value',
+      locality_a: 'original locality_a value',
+      borough: 'original borough value',
+      borough_gid: 'original borough_gid value',
+      borough_a: 'original borough_a value',
+      neighbourhood: 'original neighbourhood value',
+      neighbourhood_gid: 'original neighbourhood_gid value',
+      label: 'original label value'
+    };
+
+    const expected = {
+      unknown_field: 'original unknown_field value',
+      housenumber: 'housenumber value',
+      street: 'street value',
+      postalcode: 'postalcode value',
+      postalcode_gid: 'postalcode_gid value',
+      match_type: 'match_type value',
+      accuracy: 'accuracy value',
+      country: 'country value',
+      country_gid: 'country_gid value',
+      country_a: 'country_a value',
+      dependency: 'dependency value',
+      dependency_gid: 'dependency_gid value',
+      dependency_a: 'dependency_a value',
+      macroregion: 'macroregion value',
+      macroregion_gid: 'macroregion_gid value',
+      macroregion_a: 'macroregion_a value',
+      region: 'region value',
+      region_gid: 'region_gid value',
+      region_a: 'region_a value',
+      macrocounty: 'macrocounty value',
+      macrocounty_gid: 'macrocounty_gid value',
+      macrocounty_a: 'macrocounty_a value',
+      county: 'county value',
+      county_gid: 'county_gid value',
+      county_a: 'county_a value',
+      localadmin: 'localadmin value',
+      localadmin_gid: 'localadmin_gid value',
+      localadmin_a: 'localadmin_a value',
+      locality: 'locality value',
+      locality_gid: 'locality_gid value',
+      locality_a: 'locality_a value',
+      borough: 'borough value',
+      borough_gid: 'borough_gid value',
+      borough_a: 'borough_a value',
+      neighbourhood: 'neighbourhood value',
+      neighbourhood_gid: 'neighbourhood_gid value',
+      label: 'label value'
+    };
+
+    geojsonify({}, source, destination);
+
+    t.deepEqual(destination, expected);
+    t.end();
+
+  });
+
+  test('\'empty\' string-type values should be output as \'\'', t => {
+    [ [], {}, '', 17, true, null, undefined ].forEach(empty_value => {
+      const source = {
+        housenumber: empty_value,
+        street: empty_value,
+        postalcode: empty_value,
+        postalcode_gid: empty_value,
+        match_type: empty_value,
+        accuracy: empty_value,
+        country: empty_value,
+        country_gid: empty_value,
+        country_a: empty_value,
+        dependency: empty_value,
+        dependency_gid: empty_value,
+        dependency_a: empty_value,
+        macroregion: empty_value,
+        macroregion_gid: empty_value,
+        macroregion_a: empty_value,
+        region: empty_value,
+        region_gid: empty_value,
+        region_a: empty_value,
+        macrocounty: empty_value,
+        macrocounty_gid: empty_value,
+        macrocounty_a: empty_value,
+        county: empty_value,
+        county_gid: empty_value,
+        county_a: empty_value,
+        localadmin: empty_value,
+        localadmin_gid: empty_value,
+        localadmin_a: empty_value,
+        locality: empty_value,
+        locality_gid: empty_value,
+        locality_a: empty_value,
+        borough: empty_value,
+        borough_gid: empty_value,
+        borough_a: empty_value,
+        neighbourhood: empty_value,
+        neighbourhood_gid: empty_value,
+        label: empty_value
+      };
+      const destination = {};
+      const expected = {};
+
+      geojsonify({}, source, destination);
+
+      t.deepEqual(destination, expected);
+
+    });
+
+    t.end();
+
+  });
+
+  test('source arrays should be copy first value', t => {
+    const source = {
+      housenumber: ['housenumber value 1', 'housenumber value 2'],
+      street: ['street value 1', 'street value 2'],
+      postalcode: ['postalcode value 1', 'postalcode value 2'],
+      postalcode_gid: ['postalcode_gid value 1', 'postalcode_gid value 2'],
+      match_type: ['match_type value 1', 'match_type value 2'],
+      accuracy: ['accuracy value 1', 'accuracy value 2'],
+      country: ['country value 1', 'country value 2'],
+      country_gid: ['country_gid value 1', 'country_gid value 2'],
+      country_a: ['country_a value 1', 'country_a value 2'],
+      dependency: ['dependency value 1', 'dependency value 2'],
+      dependency_gid: ['dependency_gid value 1', 'dependency_gid value 2'],
+      dependency_a: ['dependency_a value 1', 'dependency_a value 2'],
+      macroregion: ['macroregion value 1', 'macroregion value 2'],
+      macroregion_gid: ['macroregion_gid value 1', 'macroregion_gid value 2'],
+      macroregion_a: ['macroregion_a value 1', 'macroregion_a value 2'],
+      region: ['region value 1', 'region value 2'],
+      region_gid: ['region_gid value 1', 'region_gid value 2'],
+      region_a: ['region_a value 1', 'region_a value 2'],
+      macrocounty: ['macrocounty value 1', 'macrocounty value 2'],
+      macrocounty_gid: ['macrocounty_gid value 1', 'macrocounty_gid value 2'],
+      macrocounty_a: ['macrocounty_a value 1', 'macrocounty_a value 2'],
+      county: ['county value 1', 'county value 2'],
+      county_gid: ['county_gid value 1', 'county_gid value 2'],
+      county_a: ['county_a value 1', 'county_a value 2'],
+      localadmin: ['localadmin value 1', 'localadmin value 2'],
+      localadmin_gid: ['localadmin_gid value 1', 'localadmin_gid value 2'],
+      localadmin_a: ['localadmin_a value 1', 'localadmin_a value 2'],
+      locality: ['locality value 1', 'locality value 2'],
+      locality_gid: ['locality_gid value 1', 'locality_gid value 2'],
+      locality_a: ['locality_a value 1', 'locality_a value 2'],
+      borough: ['borough value 1', 'borough value 2'],
+      borough_gid: ['borough_gid value 1', 'borough_gid value 2'],
+      borough_a: ['borough_a value 1', 'borough_a value 2'],
+      neighbourhood: ['neighbourhood value 1', 'neighbourhood value 2'],
+      neighbourhood_gid: ['neighbourhood_gid value 1', 'neighbourhood_gid value 2'],
+      label: ['label value 1', 'label value 2']
+    };
+    const destination = { };
+
+    const expected = {
+      housenumber: 'housenumber value 1',
+      street: 'street value 1',
+      postalcode: 'postalcode value 1',
+      postalcode_gid: 'postalcode_gid value 1',
+      match_type: 'match_type value 1',
+      accuracy: 'accuracy value 1',
+      country: 'country value 1',
+      country_gid: 'country_gid value 1',
+      country_a: 'country_a value 1',
+      dependency: 'dependency value 1',
+      dependency_gid: 'dependency_gid value 1',
+      dependency_a: 'dependency_a value 1',
+      macroregion: 'macroregion value 1',
+      macroregion_gid: 'macroregion_gid value 1',
+      macroregion_a: 'macroregion_a value 1',
+      region: 'region value 1',
+      region_gid: 'region_gid value 1',
+      region_a: 'region_a value 1',
+      macrocounty: 'macrocounty value 1',
+      macrocounty_gid: 'macrocounty_gid value 1',
+      macrocounty_a: 'macrocounty_a value 1',
+      county: 'county value 1',
+      county_gid: 'county_gid value 1',
+      county_a: 'county_a value 1',
+      localadmin: 'localadmin value 1',
+      localadmin_gid: 'localadmin_gid value 1',
+      localadmin_a: 'localadmin_a value 1',
+      locality: 'locality value 1',
+      locality_gid: 'locality_gid value 1',
+      locality_a: 'locality_a value 1',
+      borough: 'borough value 1',
+      borough_gid: 'borough_gid value 1',
+      borough_a: 'borough_a value 1',
+      neighbourhood: 'neighbourhood value 1',
+      neighbourhood_gid: 'neighbourhood_gid value 1',
+      label: 'label value 1'
+    };
+
+    geojsonify({}, source, destination);
+
+    t.deepEqual(destination, expected);
+    t.end();
+
+  });
+
+  test('non-empty objects should be converted to strings', t => {
+    // THIS TEST SHOWS THAT THE CODE DOES NOT DO WHAT IT EXPECTED
+    const source = {
+      housenumber: { housenumber: 'housenumber value'},
+      street: { street: 'street value'},
+      postalcode: { postalcode: 'postalcode value'},
+      postalcode_gid: { postalcode_gid: 'postalcode_gid value'},
+      match_type: { match_type: 'match_type value'},
+      accuracy: { accuracy: 'accuracy value'},
+      country: { country: 'country value'},
+      country_gid: { country_gid: 'country_gid value'},
+      country_a: { country_a: 'country_a value'},
+      dependency: { dependency: 'dependency value'},
+      dependency_gid: { dependency_gid: 'dependency_gid value'},
+      dependency_a: { dependency_a: 'dependency_a value'},
+      macroregion: { macroregion: 'macroregion value'},
+      macroregion_gid: { macroregion_gid: 'macroregion_gid value'},
+      macroregion_a: { macroregion_a: 'macroregion_a value'},
+      region: { region: 'region value'},
+      region_gid: { region_gid: 'region_gid value'},
+      region_a: { region_a: 'region_a value'},
+      macrocounty: { macrocounty: 'macrocounty value'},
+      macrocounty_gid: { macrocounty_gid: 'macrocounty_gid value'},
+      macrocounty_a: { macrocounty_a: 'macrocounty_a value'},
+      county: { county: 'county value'},
+      county_gid: { county_gid: 'county_gid value'},
+      county_a: { county_a: 'county_a value'},
+      localadmin: { localadmin: 'localadmin value'},
+      localadmin_gid: { localadmin_gid: 'localadmin_gid value'},
+      localadmin_a: { localadmin_a: 'localadmin_a value'},
+      locality: { locality: 'locality value'},
+      locality_gid: { locality_gid: 'locality_gid value'},
+      locality_a: { locality_a: 'locality_a value'},
+      borough: { borough: 'borough value'},
+      borough_gid: { borough_gid: 'borough_gid value'},
+      borough_a: { borough_a: 'borough_a value'},
+      neighbourhood: { neighbourhood: 'neighbourhood value'},
+      neighbourhood_gid: { neighbourhood_gid: 'neighbourhood_gid value'},
+      label: { label: 'label value'}
+    };
+    const destination = { };
+
+    const expected = {
+      housenumber: '[object Object]',
+      street: '[object Object]',
+      postalcode: '[object Object]',
+      postalcode_gid: '[object Object]',
+      match_type: '[object Object]',
+      accuracy: '[object Object]',
+      country: '[object Object]',
+      country_gid: '[object Object]',
+      country_a: '[object Object]',
+      dependency: '[object Object]',
+      dependency_gid: '[object Object]',
+      dependency_a: '[object Object]',
+      macroregion: '[object Object]',
+      macroregion_gid: '[object Object]',
+      macroregion_a: '[object Object]',
+      region: '[object Object]',
+      region_gid: '[object Object]',
+      region_a: '[object Object]',
+      macrocounty: '[object Object]',
+      macrocounty_gid: '[object Object]',
+      macrocounty_a: '[object Object]',
+      county: '[object Object]',
+      county_gid: '[object Object]',
+      county_a: '[object Object]',
+      localadmin: '[object Object]',
+      localadmin_gid: '[object Object]',
+      localadmin_a: '[object Object]',
+      locality: '[object Object]',
+      locality_gid: '[object Object]',
+      locality_a: '[object Object]',
+      borough: '[object Object]',
+      borough_gid: '[object Object]',
+      borough_a: '[object Object]',
+      neighbourhood: '[object Object]',
+      neighbourhood_gid: '[object Object]',
+      label: '[object Object]'
+    };
+
+    geojsonify({}, source, destination);
+
+    t.deepEqual(destination, expected);
+    t.end();
+
+  });
+
+  test('\'default\'-type properties should be copied without type conversion and overwrite old values', t => {
+    [ 'this is a string', 17.3, { a: 1 }, [1, 2, 3] ].forEach(value => {
+      const source = {
+        confidence: value,
+        distance: value,
+        bounding_box: value
+      };
+      const destination = {
+        confidence: 'original confidence value',
+        distance: 'original distance value',
+        bounding_box: 'original bounding_box value'
+      };
+
+      const expected = {
+        confidence: value,
+        distance: value,
+        bounding_box: value
+      };
+
+      geojsonify({}, source, destination);
+
+      t.deepEqual(destination, expected);
+
+    });
+
+    t.end();
+
+  });
+
+  test('\'default\'-type properties that are numbers should be output as numbers', t => {
+    [ 17, 17.3 ].forEach(value => {
+      const source = {
+        confidence: value,
+        distance: value,
+        bounding_box: value
+      };
+      const destination = {};
+      const expected = {
+        confidence: value,
+        distance: value,
+        bounding_box: value
+      };
+
+      geojsonify({}, source, destination);
+
+      t.deepEqual(destination, expected);
+
+    });
+
+    t.end();
+
+  });
+
+  test('\'empty\' values for default-type properties should not be output', t => {
+    [ undefined, null, true, {}, [] ].forEach(value => {
+      const source = {
+        confidence: value,
+        distance: value,
+        bounding_box: value
+      };
+      const destination = {};
+      const expected = {};
+
+      geojsonify({}, source, destination);
+
+      t.deepEqual(destination, expected);
+
+    });
+
+    t.end();
+
+  });
+
+  test('array-type properties should not be output when empty', t => {
+    const source = {
+      category: []
+    };
+    const destination = {};
+    const expected = {};
+
+    geojsonify({}, source, destination);
+
+    t.deepEqual(destination, expected);
+    t.end();
+
+  });
+
+  test('array-type properties with array values should be output as arrays', t => {
+    const source = {
+      category: [ 1, 2 ]
+    };
+    const destination = {};
+    const expected = {
+      category: [ 1, 2 ]
+    };
+
+    const clean = {
+      categories: true
+    };
+
+    geojsonify(clean, source, destination);
+
+    t.deepEqual(destination, expected);
+    t.end();
+
+  });
+
+  test('category property should be output when params contains \'category\' property', t => {
+    [ {a: 1}, 'this is a string'].forEach(value => {
+      const source = {
+        category: value
+      };
+      const destination = {};
+      const expected = {
+        category: [ value ]
+      };
+
+      const clean = {
+        categories: true
+      };
+
+      geojsonify(clean, source, destination);
+
+      t.deepEqual(destination, expected);
+
+    });
+
+    t.end();
+
+  });
+
+  test('category property should not be output when params does not contain \'category\' property', t => {
+    const source = {
+      category: [ 1, 2 ]
+    };
+    const destination = {};
+    const expected = {
+    };
+
+    const clean = {};
+
+    geojsonify(clean, source, destination);
+
+    t.deepEqual(destination, expected);
+    t.end();
+
+  });
+
+  test('category property should not be output when params is not an object', t => {
+    const source = {
+      category: [ 1, 2 ]
+    };
+    const destination = {};
+    const expected = {
+    };
+
+    const clean = 'this is not an object';
+
+    geojsonify(clean, source, destination);
+
+    t.deepEqual(destination, expected);
+    t.end();
+
+  });
+
+};
+
+module.exports.all = (tape, common) => {
+
+  function test(name, testFunction) {
+    return tape(`geojsonify: ${name}`, testFunction);
+  }
+
+  for( var testCase in module.exports.tests ){
+    module.exports.tests[testCase](test, common);
+  }
+};
diff --git a/test/unit/run.js b/test/unit/run.js
index 0cd9d4c9..5631b9f3 100644
--- a/test/unit/run.js
+++ b/test/unit/run.js
@@ -31,6 +31,7 @@ var tests = [
   require('./controller/predicates/is_request_sources_only_whosonfirst'),
   require('./helper/debug'),
   require('./helper/diffPlaces'),
+  require('./helper/geojsonify_place_details'),
   require('./helper/geojsonify'),
   require('./helper/logging'),
   require('./helper/type_mapping'),