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
176
|
use crate::error::Error;
use crate::expr::*;
use dhall_syntax::*;
use std::collections::HashMap;
use std::fs::File;
use std::io::Read;
use std::path::Path;
use std::path::PathBuf;
#[derive(Debug)]
pub enum ImportError {
Recursive(Import, Box<Error>),
UnexpectedImport(Import),
ImportCycle(ImportStack, Import),
}
/// A root from which to resolve relative imports.
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum ImportRoot {
LocalDir(PathBuf),
}
type ImportCache = HashMap<Import, Normalized<'static>>;
type ImportStack = Vec<Import>;
fn resolve_import(
import: &Import,
root: &ImportRoot,
import_cache: &mut ImportCache,
import_stack: &ImportStack,
) -> Result<Normalized<'static>, ImportError> {
use self::ImportRoot::*;
use dhall_syntax::FilePrefix::*;
use dhall_syntax::ImportLocation::*;
let cwd = match root {
LocalDir(cwd) => cwd,
};
match &import.location_hashed.location {
Local(prefix, path) => {
let path = match prefix {
// TODO: fail gracefully
Parent => cwd.parent().unwrap().join(path),
Here => cwd.join(path),
_ => unimplemented!("{:?}", import),
};
Ok(load_import(&path, import_cache, import_stack).map_err(|e| {
ImportError::Recursive(import.clone(), Box::new(e))
})?)
}
_ => unimplemented!("{:?}", import),
}
}
fn load_import(
f: &Path,
import_cache: &mut ImportCache,
import_stack: &ImportStack,
) -> Result<Normalized<'static>, Error> {
Ok(
do_resolve_expr(Parsed::parse_file(f)?, import_cache, import_stack)?
.typecheck()?
.normalize(),
)
}
fn do_resolve_expr<'a>(
Parsed(expr, root): Parsed<'a>,
import_cache: &mut ImportCache,
import_stack: &ImportStack,
) -> Result<Resolved<'a>, ImportError> {
let resolve =
|import: &Import| -> Result<Normalized<'static>, ImportError> {
if import_stack.contains(import) {
return Err(ImportError::ImportCycle(
import_stack.clone(),
import.clone(),
));
}
match import_cache.get(import) {
Some(expr) => Ok(expr.clone()),
None => {
// Copy the import stack and push the current import
let mut import_stack = import_stack.clone();
import_stack.push(import.clone());
// Resolve the import recursively
let expr = resolve_import(
import,
&root,
import_cache,
&import_stack,
)?;
// Add the import to the cache
import_cache.insert(import.clone(), expr.clone());
Ok(expr)
}
}
};
let expr = expr.traverse_embed(resolve)?;
Ok(Resolved(expr))
}
fn skip_resolve_expr(
Parsed(expr, _root): Parsed<'_>,
) -> Result<Resolved<'_>, ImportError> {
let resolve =
|import: &Import| -> Result<Normalized<'static>, ImportError> {
Err(ImportError::UnexpectedImport(import.clone()))
};
let expr = expr.traverse_embed(resolve)?;
Ok(Resolved(expr))
}
impl<'a> Parsed<'a> {
pub fn parse_file(f: &Path) -> Result<Parsed<'a>, Error> {
let mut buffer = String::new();
File::open(f)?.read_to_string(&mut buffer)?;
let expr = parse_expr(&*buffer)?;
let root = ImportRoot::LocalDir(f.parent().unwrap().to_owned());
Ok(Parsed(expr.unnote().note_absurd(), root))
}
pub fn parse_str(s: &'a str) -> Result<Parsed<'a>, Error> {
let expr = parse_expr(s)?;
let root = ImportRoot::LocalDir(std::env::current_dir()?);
Ok(Parsed(expr, root))
}
#[allow(dead_code)]
pub fn parse_binary_file(f: &Path) -> Result<Parsed<'a>, Error> {
let mut buffer = Vec::new();
File::open(f)?.read_to_end(&mut buffer)?;
let expr = crate::binary::decode(&buffer)?;
let root = ImportRoot::LocalDir(f.parent().unwrap().to_owned());
Ok(Parsed(expr.note_absurd(), root))
}
pub fn resolve(self) -> Result<Resolved<'a>, ImportError> {
crate::imports::do_resolve_expr(self, &mut HashMap::new(), &Vec::new())
}
#[allow(dead_code)]
pub fn skip_resolve(self) -> Result<Resolved<'a>, ImportError> {
crate::imports::skip_resolve_expr(self)
}
}
#[cfg(test)]
mod spec_tests {
#![rustfmt::skip]
macro_rules! import_success {
($name:ident, $path:expr) => {
make_spec_test!(Import, Success, $name, $path);
};
}
// macro_rules! import_failure {
// ($name:ident, $path:expr) => {
// make_spec_test!(Import, Failure, $name, $path);
// };
// }
// import_success!(success_alternativeEnvNatural, "alternativeEnvNatural");
// import_success!(success_alternativeEnvSimple, "alternativeEnvSimple");
// import_success!(success_alternativeNatural, "alternativeNatural");
// import_success!(success_asText, "asText");
import_success!(success_fieldOrder, "fieldOrder");
// import_failure!(failure_alternativeEnv, "alternativeEnv");
// import_failure!(failure_alternativeEnvMissing, "alternativeEnvMissing");
// import_failure!(failure_cycle, "cycle");
// import_failure!(failure_missing, "missing");
// import_failure!(failure_referentiallyInsane, "referentiallyInsane");
}
|
