1 | #[derive (Copy, Clone)] |
2 | pub(crate) struct EscapeOptions { |
3 | /// Produce \'. |
4 | pub escape_single_quote: bool, |
5 | /// Produce \". |
6 | pub escape_double_quote: bool, |
7 | /// Produce \x escapes for non-ASCII, and use \x rather than \u for ASCII |
8 | /// control characters. |
9 | pub escape_nonascii: bool, |
10 | } |
11 | |
12 | pub(crate) fn escape_bytes(bytes: &[u8], opt: EscapeOptions) -> String { |
13 | let mut repr: String = String::new(); |
14 | |
15 | if opt.escape_nonascii { |
16 | for &byte: u8 in bytes { |
17 | escape_single_byte(byte, opt, &mut repr); |
18 | } |
19 | } else { |
20 | let mut chunks: Utf8Chunks<'_> = bytes.utf8_chunks(); |
21 | while let Some(chunk: Utf8Chunk<'_>) = chunks.next() { |
22 | for ch: char in chunk.valid().chars() { |
23 | escape_single_char(ch, opt, &mut repr); |
24 | } |
25 | for &byte: u8 in chunk.invalid() { |
26 | escape_single_byte(byte, opt, &mut repr); |
27 | } |
28 | } |
29 | } |
30 | |
31 | repr |
32 | } |
33 | |
34 | fn escape_single_byte(byte: u8, opt: EscapeOptions, repr: &mut String) { |
35 | if byte == b' \0' { |
36 | repr.push_str(string:" \\0" ); |
37 | } else if (byte == b' \'' && !opt.escape_single_quote) |
38 | || (byte == b'"' && !opt.escape_double_quote) |
39 | { |
40 | repr.push(ch:byte as char); |
41 | } else { |
42 | // Escapes \t, \r, \n, \\, \', \", and uses \x## for non-ASCII and |
43 | // for ASCII control characters. |
44 | repr.extend(iter:byte.escape_ascii().map(char::from)); |
45 | } |
46 | } |
47 | |
48 | fn escape_single_char(ch: char, opt: EscapeOptions, repr: &mut String) { |
49 | if (ch == ' \'' && !opt.escape_single_quote) || (ch == '"' && !opt.escape_double_quote) { |
50 | repr.push(ch); |
51 | } else { |
52 | // Escapes \0, \t, \r, \n, \\, \', \", and uses \u{...} for |
53 | // non-printable characters and for Grapheme_Extend characters, which |
54 | // includes things like U+0300 "Combining Grave Accent". |
55 | repr.extend(iter:ch.escape_debug()); |
56 | } |
57 | } |
58 | |