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
|
//! The preprocessing we apply to doc comments.
//!
//! #[derive(IniMap)] works in terms of "paragraphs". Paragraph is a sequence of
//! non-empty adjacent lines, delimited by sequences of blank (whitespace only) lines.
use std::iter;
pub fn extract_doc_comment(attrs: &[syn::Attribute]) -> Vec<String> {
use syn::Lit::*;
use syn::Meta::*;
use syn::MetaNameValue;
// multiline comments (`/** ... */`) may have LFs (`\n`) in them,
// we need to split so we could handle the lines correctly
//
// we also need to remove leading and trailing blank lines
let mut lines: Vec<_> = attrs
.iter()
.filter(|attr| attr.path.is_ident("doc"))
.filter_map(|attr| {
if let Ok(NameValue(MetaNameValue { lit: Str(s), .. })) = attr.parse_meta() {
Some(s.value())
} else {
// non #[doc = "..."] attributes are not our concern
// we leave them for rustc to handle
None
}
})
.skip_while(|s| is_blank(s))
.flat_map(|s| {
let lines = s
.split('\n')
.map(|s| {
// remove one leading space no matter what
let s = s.strip_prefix(' ').unwrap_or(s);
s.to_owned()
})
.collect::<Vec<_>>();
lines
})
.collect();
while let Some(true) = lines.last().map(|s| is_blank(s)) {
lines.pop();
}
lines
}
pub fn format_doc_comment(
lines: &[String],
preprocess: bool,
force_long: bool,
) -> (Option<String>, Option<String>) {
if let Some(first_blank) = lines.iter().position(|s| is_blank(s)) {
let (short, long) = if preprocess {
let paragraphs = split_paragraphs(lines);
let short = paragraphs[0].clone();
let long = paragraphs.join("\n\n");
(remove_period(short), long)
} else {
let short = lines[..first_blank].join("\n");
let long = lines.join("\n");
(short, long)
};
(Some(short), Some(long))
} else {
let (short, long) = if preprocess {
let short = merge_lines(lines);
let long = force_long.then(|| short.clone());
let short = remove_period(short);
(short, long)
} else {
let short = lines.join("\n");
let long = force_long.then(|| short.clone());
(short, long)
};
(Some(short), long)
}
}
fn split_paragraphs(lines: &[String]) -> Vec<String> {
let mut last_line = 0;
iter::from_fn(|| {
let slice = &lines[last_line..];
let start = slice.iter().position(|s| !is_blank(s)).unwrap_or(0);
let slice = &slice[start..];
let len = slice
.iter()
.position(|s| is_blank(s))
.unwrap_or(slice.len());
last_line += start + len;
if len != 0 {
Some(merge_lines(&slice[..len]))
} else {
None
}
})
.collect()
}
fn remove_period(mut s: String) -> String {
if s.ends_with('.') && !s.ends_with("..") {
s.pop();
}
s
}
fn is_blank(s: &str) -> bool {
s.trim().is_empty()
}
fn merge_lines(lines: impl IntoIterator<Item = impl AsRef<str>>) -> String {
lines
.into_iter()
.map(|s| s.as_ref().trim().to_owned())
.collect::<Vec<_>>()
.join(" ")
}
|
