1  var concatMap = require('../');
 2  var test = require('tape');
 3  
 4  test('empty or not', function (t) {
 5      var xs = [ 1, 2, 3, 4, 5, 6 ];
 6      var ixes = [];
 7      var ys = concatMap(xs, function (x, ix) {
 8          ixes.push(ix);
 9          return x % 2 ? [ x - 0.1, x, x + 0.1 ] : [];
10      });
11      t.same(ys, [ 0.9, 1, 1.1, 2.9, 3, 3.1, 4.9, 5, 5.1 ]);
12      t.same(ixes, [ 0, 1, 2, 3, 4, 5 ]);
13      t.end();
14  });
15  
16  test('always something', function (t) {
17      var xs = [ 'a', 'b', 'c', 'd' ];
18      var ys = concatMap(xs, function (x) {
19          return x === 'b' ? [ 'B', 'B', 'B' ] : [ x ];
20      });
21      t.same(ys, [ 'a', 'B', 'B', 'B', 'c', 'd' ]);
22      t.end();
23  });
24  
25  test('scalars', function (t) {
26      var xs = [ 'a', 'b', 'c', 'd' ];
27      var ys = concatMap(xs, function (x) {
28          return x === 'b' ? [ 'B', 'B', 'B' ] : x;
29      });
30      t.same(ys, [ 'a', 'B', 'B', 'B', 'c', 'd' ]);
31      t.end();
32  });
33  
34  test('undefs', function (t) {
35      var xs = [ 'a', 'b', 'c', 'd' ];
36      var ys = concatMap(xs, function () {});
37      t.same(ys, [ undefined, undefined, undefined, undefined ]);
38      t.end();
39  });