map.js (1075B)
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 });