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1"use strict";
2
3const O = Object
4 , { first, strlen } = require ('printable-characters') // handles ANSI codes and invisible characters
5 , limit = (s, n) => (first (s, n - 1) + '…')
6
7const asColumns = (rows, cfg_) => {
8
9 const
10
11 zip = (arrs, f) => arrs.reduce ((a, b) => b.map ((b, i) => [...a[i] || [], b]), []).map (args => f (...args)),
12
13 /* Convert cell data to string (converting multiline text to singleline) */
14
15 cells = rows.map (r => r.map (c => (c === undefined) ? '' : cfg_.print (c).replace (/\n/g, '\\n'))),
16
17 /* Compute column widths (per row) and max widths (per column) */
18
19 cellWidths = cells.map (r => r.map (strlen)),
20 maxWidths = zip (cellWidths, Math.max),
21
22 /* Default config */
23
24 cfg = O.assign ({
25 delimiter: ' ',
26 minColumnWidths: maxWidths.map (x => 0),
27 maxTotalWidth: 0 }, cfg_),
28
29 delimiterLength = strlen (cfg.delimiter),
30
31 /* Project desired column widths, taking maxTotalWidth and minColumnWidths in account. */
32
33 totalWidth = maxWidths.reduce ((a, b) => a + b, 0),
34 relativeWidths = maxWidths.map (w => w / totalWidth),
35 maxTotalWidth = cfg.maxTotalWidth - (delimiterLength * (maxWidths.length - 1)),
36 excessWidth = Math.max (0, totalWidth - maxTotalWidth),
37 computedWidths = zip ([cfg.minColumnWidths, maxWidths, relativeWidths],
38 (min, max, relative) => Math.max (min, Math.floor (max - excessWidth * relative))),
39
40 /* This is how many symbols we should pad or cut (per column). */
41
42 restCellWidths = cellWidths.map (widths => zip ([computedWidths, widths], (a, b) => a - b))
43
44 /* Perform final composition. */
45
46 return zip ([cells, restCellWidths], (a, b) =>
47 zip ([a, b], (str, w) => (w >= 0)
48 ? (str + ' '.repeat (w))
49 : (limit (str, strlen (str) + w))).join (cfg.delimiter))
50}
51
52const asTable = cfg => O.assign (arr => {
53
54/* Print arrays */
55
56 if (arr[0] && Array.isArray (arr[0]))
57 return asColumns (arr, cfg).join ('\n')
58
59/* Print objects */
60
61 const colNames = [...new Set ([].concat (...arr.map (O.keys)))],
62 columns = [colNames.map (cfg.title), ...arr.map (o => colNames.map (key => o[key]))],
63 lines = asColumns (columns, cfg)
64
65 return [lines[0], cfg.dash.repeat (strlen (lines[0])), ...lines.slice (1)].join ('\n')
66
67}, cfg, {
68
69 configure: newConfig => asTable (O.assign ({}, cfg, newConfig)),
70})
71
72module.exports = asTable ({
73
74 maxTotalWidth: Number.MAX_SAFE_INTEGER,
75 print: String,
76 title: String,
77 dash: '-'
78})
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