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
|
use std::collections::HashMap;
use std::path::{Path, PathBuf};
use dhall_syntax::Import;
use crate::error::{Error, ImportError};
use crate::phase::{Normalized, Parsed, Resolved};
/// A root from which to resolve relative imports.
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum ImportRoot {
LocalDir(PathBuf),
}
type ImportCache = HashMap<Import, Normalized>;
pub(crate) type ImportStack = Vec<Import>;
fn resolve_import(
import: &Import,
root: &ImportRoot,
import_cache: &mut ImportCache,
import_stack: &ImportStack,
) -> Result<Normalized, 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, Error> {
Ok(
do_resolve_expr(Parsed::parse_file(f)?, import_cache, import_stack)?
.typecheck()?
.normalize(),
)
}
fn do_resolve_expr(
Parsed(expr, root): Parsed,
import_cache: &mut ImportCache,
import_stack: &ImportStack,
) -> Result<Resolved, ImportError> {
let resolve = |import: &Import| -> Result<Normalized, 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))
}
pub(crate) fn resolve(e: Parsed) -> Result<Resolved, ImportError> {
do_resolve_expr(e, &mut HashMap::new(), &Vec::new())
}
pub(crate) fn skip_resolve_expr(
Parsed(expr, _root): Parsed,
) -> Result<Resolved, ImportError> {
let resolve = |import: &Import| -> Result<Normalized, ImportError> {
Err(ImportError::UnexpectedImport(import.clone()))
};
let expr = expr.traverse_embed(resolve)?;
Ok(Resolved(expr))
}
#[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");
}
|