use crate::compile::ModuleDependencyMap;
use petgraph::{algo::is_cyclic_directed, Graph};
use std::{collections::HashMap, path::Path};
use super::ValidationError;
pub fn validate_modules(modules: &ModuleDependencyMap) -> Result<(), ValidationError> {
if is_module_dependency_circular(modules) {
return Err(ValidationError::CircularModuleDependency);
}
Ok(())
}
fn is_module_dependency_circular(modules: &ModuleDependencyMap) -> bool {
let mut graph = Graph::<&Path, ()>::new();
let mut indices = HashMap::<&Path, _>::new();
for output in modules.keys() {
indices.insert(output, graph.add_node(output));
}
for (output, build) in modules {
for input in build.values() {
graph.add_edge(indices[output.as_path()], indices[input.as_path()], ());
}
}
is_cyclic_directed(&graph)
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn validate_empty() {
assert_eq!(validate_modules(&Default::default()), Ok(()));
}
#[test]
fn validate_module() {
assert_eq!(
validate_modules(&[("foo".into(), Default::default())].into_iter().collect()),
Ok(())
);
}
#[test]
fn validate_circular_module() {
assert_eq!(
validate_modules(
&[(
"foo".into(),
[("foo".into(), "foo".into())].into_iter().collect()
)]
.into_iter()
.collect()
),
Err(ValidationError::CircularModuleDependency)
);
}
#[test]
fn validate_two_modules() {
assert_eq!(
validate_modules(
&[
(
"foo".into(),
[("bar".into(), "bar".into())].into_iter().collect()
),
("bar".into(), Default::default(),)
]
.into_iter()
.collect()
),
Ok(())
);
}
#[test]
fn validate_two_circular_modules() {
assert_eq!(
validate_modules(
&[
(
"foo".into(),
[("bar".into(), "bar".into())].into_iter().collect()
),
(
"bar".into(),
[("foo".into(), "foo".into())].into_iter().collect()
),
]
.into_iter()
.collect()
),
Err(ValidationError::CircularModuleDependency)
);
}
}