1use std::borrow::Cow;
2use std::fmt::{self, Display};
3use std::str::FromStr;
4
5use anyhow::{ensure, Error, Result};
6use serde::Serialize;
7use wasm_encoder::{ComponentSection, CustomSection, Encode, Section};
8use wasmparser::CustomSectionReader;
9
10/// Contact details of the people or organization responsible,
11/// encoded as a freeform string.
12#[derive(Debug, Clone, PartialEq)]
13pub struct Author(CustomSection<'static>);
14
15impl Author {
16 /// Create a new instance of `Author`.
17 pub fn new<S: Into<Cow<'static, str>>>(s: S) -> Self {
18 Self(CustomSection {
19 name: "author".into(),
20 data: match s.into() {
21 Cow::Borrowed(s: &str) => Cow::Borrowed(s.as_bytes()),
22 Cow::Owned(s: String) => Cow::Owned(s.into()),
23 },
24 })
25 }
26
27 /// Parse an `author` custom section from a wasm binary.
28 pub(crate) fn parse_custom_section(reader: &CustomSectionReader<'_>) -> Result<Self> {
29 ensure!(
30 reader.name() == "author",
31 "The `author` custom section should have a name of 'author'"
32 );
33 let data: String = String::from_utf8(vec:reader.data().to_owned())?;
34 Ok(Self::new(data))
35 }
36}
37
38impl FromStr for Author {
39 type Err = Error;
40
41 fn from_str(s: &str) -> Result<Self, Self::Err> {
42 Ok(Self::new(s.to_owned()))
43 }
44}
45
46impl Serialize for Author {
47 fn serialize<S>(&self, serializer: S) -> std::result::Result<S::Ok, S::Error>
48 where
49 S: serde::Serializer,
50 {
51 serializer.serialize_str(&self.to_string())
52 }
53}
54
55impl Display for Author {
56 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
57 // NOTE: this will never panic since we always guarantee the data is
58 // encoded as utf8, even if we internally store it as [u8].
59 let data: String = String::from_utf8(self.0.data.to_vec()).unwrap();
60 write!(f, "{data}")
61 }
62}
63
64impl ComponentSection for Author {
65 fn id(&self) -> u8 {
66 ComponentSection::id(&self.0)
67 }
68}
69
70impl Section for Author {
71 fn id(&self) -> u8 {
72 Section::id(&self.0)
73 }
74}
75
76impl Encode for Author {
77 fn encode(&self, sink: &mut Vec<u8>) {
78 self.0.encode(sink);
79 }
80}
81
82#[cfg(test)]
83mod test {
84 use super::*;
85 use wasm_encoder::Component;
86 use wasmparser::Payload;
87
88 #[test]
89 fn roundtrip() {
90 let mut component = Component::new();
91 component.section(&Author::new("Nori Cat"));
92 let component = component.finish();
93
94 let mut parsed = false;
95 for section in wasmparser::Parser::new(0).parse_all(&component) {
96 if let Payload::CustomSection(reader) = section.unwrap() {
97 let author = Author::parse_custom_section(&reader).unwrap();
98 assert_eq!(author.to_string(), "Nori Cat");
99 parsed = true;
100 }
101 }
102 assert!(parsed);
103 }
104
105 #[test]
106 fn serialize() {
107 let author = Author::new("Chashu Cat");
108 let json = serde_json::to_string(&author).unwrap();
109 assert_eq!(r#""Chashu Cat""#, json);
110 }
111}
112