Try to work on build some more.

crates/core/src/prey.rs

@@ -1,13 +1,14 @@
 use std::collections::HashSet;
 use std::fs::{File, OpenOptions};
 use std::io::Read;
-use std::path::PathBuf;
+use std::path::{Path, PathBuf};
 
 use serde::{Deserialize, Serialize};
 
 use crate::class::Class;
 use crate::meta::Meta;
 use crate::package::Package;
+use crate::prelude::Dependency;
 
 pub const F_PREY_TOML: &str = "Prey.toml";
 pub const F_PREY_LOCK: &str = "Prey.lock";
@@ -53,11 +54,19 @@ impl TryFrom<File> for Prey {
 }
 
 /// Data struct
-#[derive(Debug, Clone, Deserialize, Serialize, PartialEq, Eq)]
+#[derive(Debug, Clone, Default, Deserialize, Serialize, PartialEq, Eq)]
 pub struct PreyLock {
-    classes: HashSet<Class>,
+    pub classes: HashSet<Class>,
 }
 
+impl PreyLock {
+    pub fn with_class(&mut self, class: Class) -> &mut Self {
+        self.classes.insert(class);
+        self
+    }
+}
+
+/// Load the PreyLock from Prey.lock file.
 impl TryFrom<PathBuf> for PreyLock {
     type Error = crate::Error;
 
@@ -76,3 +85,21 @@ impl TryFrom<File> for PreyLock {
         Ok(toml::from_str(buf.as_str())?)
     }
 }
+
+impl From<Vec<PathBuf>> for PreyLock {
+    fn from(value: Vec<PathBuf>) -> Self {
+        let mut lock = Self::default();
+        lock.classes = value
+            .iter()
+            .filter_map(|f| {
+                let dep = Class::try_from(f.to_owned());
+                if dep.is_ok() {
+                    Some(dep.unwrap())
+                } else {
+                    None
+                }
+            })
+            .collect();
+        lock
+    }
+}