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
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
|
/// The beginning of a file path which anchors subsequent path components
#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
pub enum FilePrefix {
/// Absolute path
Absolute,
/// Path relative to .
Here,
/// Path relative to ..
Parent,
/// Path relative to ~
Home,
}
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
pub struct File {
pub file_path: Vec<String>,
}
/// The location of import (i.e. local vs. remote vs. environment)
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
pub enum ImportLocation<SubExpr> {
Local(FilePrefix, File),
Remote(URL<SubExpr>),
Env(String),
Missing,
}
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
pub struct URL<SubExpr> {
pub scheme: Scheme,
pub authority: String,
pub path: File,
pub query: Option<String>,
pub headers: Option<SubExpr>,
}
#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
pub enum Scheme {
HTTP,
HTTPS,
}
/// How to interpret the import's contents (i.e. as Dhall code or raw text)
#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
pub enum ImportMode {
Code,
RawText,
Location,
}
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
pub enum Hash {
SHA256(Vec<u8>),
}
/// Reference to an external resource
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
pub struct Import<SubExpr> {
pub mode: ImportMode,
pub location: ImportLocation<SubExpr>,
pub hash: Option<Hash>,
}
impl<SE> URL<SE> {
pub fn visit_subexpr<'a, Err, SE2>(
&'a self,
f: impl FnOnce(&'a SE) -> Result<SE2, Err>,
) -> Result<URL<SE2>, Err> {
let headers = self.headers.as_ref().map(f).transpose()?;
Ok(URL {
scheme: self.scheme,
authority: self.authority.clone(),
path: self.path.clone(),
query: self.query.clone(),
headers,
})
}
}
impl<SE> ImportLocation<SE> {
pub fn visit_subexpr<'a, Err, SE2>(
&'a self,
f: impl FnOnce(&'a SE) -> Result<SE2, Err>,
) -> Result<ImportLocation<SE2>, Err> {
use ImportLocation::*;
Ok(match self {
Local(prefix, path) => Local(*prefix, path.clone()),
Remote(url) => Remote(url.visit_subexpr(f)?),
Env(env) => Env(env.clone()),
Missing => Missing,
})
}
}
impl<SE> Import<SE> {
pub fn visit_subexpr<'a, Err, SE2>(
&'a self,
f: impl FnOnce(&'a SE) -> Result<SE2, Err>,
) -> Result<Import<SE2>, Err> {
Ok(Import {
mode: self.mode,
location: self.location.visit_subexpr(f)?,
hash: self.hash.clone(),
})
}
}
pub trait Canonicalize {
fn canonicalize(&self) -> Self;
}
impl Canonicalize for File {
fn canonicalize(&self) -> File {
let mut file_path = Vec::new();
let mut file_path_components = self.file_path.clone().into_iter();
loop {
let component = file_path_components.next();
match component.as_ref() {
// ───────────────────
// canonicalize(ε) = ε
None => break,
// canonicalize(directory₀) = directory₁
// ───────────────────────────────────────
// canonicalize(directory₀/.) = directory₁
Some(c) if c == "." => continue,
Some(c) if c == ".." => match file_path_components.next() {
// canonicalize(directory₀) = ε
// ────────────────────────────
// canonicalize(directory₀/..) = /..
None => file_path.push("..".to_string()),
// canonicalize(directory₀) = directory₁/..
// ──────────────────────────────────────────────
// canonicalize(directory₀/..) = directory₁/../..
Some(ref c) if c == ".." => {
file_path.push("..".to_string());
file_path.push("..".to_string());
},
// canonicalize(directory₀) = directory₁/component
// ─────────────────────────────────────────────── ; If "component" is not
// canonicalize(directory₀/..) = directory₁ ; ".."
Some(_) => continue,
},
// canonicalize(directory₀) = directory₁
// ───────────────────────────────────────────────────────── ; If no other
// canonicalize(directory₀/component) = directory₁/component ; rule matches
Some(c) => file_path.push(c.clone()),
}
}
File { file_path }
}
}
impl<SubExpr: Copy> Canonicalize for ImportLocation<SubExpr> {
fn canonicalize(&self) -> ImportLocation<SubExpr> {
match self {
ImportLocation::Local(prefix, file) => ImportLocation::Local(*prefix, file.canonicalize()),
ImportLocation::Remote(url) => ImportLocation::Remote(URL {
scheme: url.scheme,
authority: url.authority.clone(),
path: url.path.canonicalize(),
query: url.query.clone(),
headers: url.headers.clone(),
}),
ImportLocation::Env(name) => ImportLocation::Env(name.to_string()),
ImportLocation::Missing => ImportLocation::Missing,
}
}
}
|
