1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
|
// Ported from Go:
// https://github.com/golang/go/blob/go1.12.5/src/encoding/csv/
// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
import { BufReader, EOF } from "../io/bufio.ts";
import { TextProtoReader } from "../textproto/mod.ts";
const INVALID_RUNE = ["\r", "\n", '"'];
export class ParseError extends Error {
StartLine: number;
Line: number;
constructor(start: number, line: number, message: string) {
super(message);
this.StartLine = start;
this.Line = line;
}
}
export interface ParseOptions {
comma: string;
comment?: string;
trimLeadingSpace: boolean;
lazyQuotes?: boolean;
fieldsPerRecord?: number;
}
function chkOptions(opt: ParseOptions): void {
if (
INVALID_RUNE.includes(opt.comma) ||
(opt.comment && INVALID_RUNE.includes(opt.comment)) ||
opt.comma === opt.comment
) {
throw new Error("Invalid Delimiter");
}
}
export async function read(
Startline: number,
reader: BufReader,
opt: ParseOptions = { comma: ",", comment: "#", trimLeadingSpace: false }
): Promise<string[] | EOF> {
const tp = new TextProtoReader(reader);
let line: string;
let result: string[] = [];
let lineIndex = Startline;
const r = await tp.readLine();
if (r === EOF) return EOF;
line = r;
// Normalize \r\n to \n on all input lines.
if (
line.length >= 2 &&
line[line.length - 2] === "\r" &&
line[line.length - 1] === "\n"
) {
line = line.substring(0, line.length - 2);
line = line + "\n";
}
const trimmedLine = line.trimLeft();
if (trimmedLine.length === 0) {
return [];
}
// line starting with comment character is ignored
if (opt.comment && trimmedLine[0] === opt.comment) {
return [];
}
result = line.split(opt.comma);
let quoteError = false;
result = result.map(
(r): string => {
if (opt.trimLeadingSpace) {
r = r.trimLeft();
}
if (r[0] === '"' && r[r.length - 1] === '"') {
r = r.substring(1, r.length - 1);
} else if (r[0] === '"') {
r = r.substring(1, r.length);
}
if (!opt.lazyQuotes) {
if (r[0] !== '"' && r.indexOf('"') !== -1) {
quoteError = true;
}
}
return r;
}
);
if (quoteError) {
throw new ParseError(Startline, lineIndex, 'bare " in non-quoted-field');
}
return result;
}
export async function readAll(
reader: BufReader,
opt: ParseOptions = {
comma: ",",
trimLeadingSpace: false,
lazyQuotes: false
}
): Promise<string[][]> {
const result: string[][] = [];
let _nbFields: number;
let lineResult: string[];
let first = true;
let lineIndex = 0;
chkOptions(opt);
for (;;) {
const r = await read(lineIndex, reader, opt);
if (r === EOF) break;
lineResult = r;
lineIndex++;
// If fieldsPerRecord is 0, Read sets it to
// the number of fields in the first record
if (first) {
first = false;
if (opt.fieldsPerRecord !== undefined) {
if (opt.fieldsPerRecord === 0) {
_nbFields = lineResult.length;
} else {
_nbFields = opt.fieldsPerRecord;
}
}
}
if (lineResult.length > 0) {
if (_nbFields! && _nbFields! !== lineResult.length) {
throw new ParseError(lineIndex, lineIndex, "wrong number of fields");
}
result.push(lineResult);
}
}
return result;
}
|
