From 2d25b15f3c8898d9fc07edab6a21d983b6da950f Mon Sep 17 00:00:00 2001
From: Wojciech Kozlowski <wk@wojciechkozlowski.eu>
Date: Sun, 7 Jan 2024 11:04:06 +0100
Subject: [PATCH] Add unit tests

---
 src/database/mod.rs | 31 ++++++++++++++++++++++++++++++-
 src/lib.rs          | 31 ++++++++++++++++++++++++++++++-
 src/library/mod.rs  | 18 +++++++++++++++++-
 3 files changed, 77 insertions(+), 3 deletions(-)

diff --git a/src/database/mod.rs b/src/database/mod.rs
index 3846314..f2747e1 100644
--- a/src/database/mod.rs
+++ b/src/database/mod.rs
@@ -20,6 +20,19 @@ pub trait IDatabase {
     fn save<S: Serialize + 'static>(&mut self, collection: &S) -> Result<(), SaveError>;
 }
 
+/// Non-implementation defined to make generics easier.
+pub struct NoDatabase {}
+
+impl IDatabase for NoDatabase {
+    fn load<D: DeserializeOwned + 'static>(&self, _collection: &mut D) -> Result<(), LoadError> {
+        panic!()
+    }
+
+    fn save<S: Serialize + 'static>(&mut self, _collection: &S) -> Result<(), SaveError> {
+        panic!()
+    }
+}
+
 /// Error type for database calls.
 #[derive(Debug)]
 pub enum LoadError {
@@ -76,7 +89,23 @@ impl From<std::io::Error> for SaveError {
 mod tests {
     use std::io;
 
-    use super::{LoadError, SaveError};
+    use super::{LoadError, SaveError, NoDatabase, IDatabase};
+
+    #[test]
+    #[should_panic]
+    fn no_database_load() {
+        let database = NoDatabase {};
+        let mut collection: Vec<String> = vec![];
+        _ = database.load(&mut collection);
+    }
+
+    #[test]
+    #[should_panic]
+    fn no_database_save() {
+        let mut database = NoDatabase {};
+        let collection: Vec<String> = vec![];
+        _ = database.save(&collection);
+    }
 
     #[test]
     fn errors() {
diff --git a/src/lib.rs b/src/lib.rs
index 1aa823c..2653aac 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -616,7 +616,7 @@ mod tests {
     use mockall::predicate;
     use once_cell::sync::Lazy;
 
-    use crate::{database::MockIDatabase, library::MockILibrary};
+    use crate::{database::{MockIDatabase, NoDatabase}, library::{MockILibrary, NoLibrary}};
 
     use super::*;
 
@@ -961,6 +961,18 @@ mod tests {
         music_hoard.save_to_database().unwrap();
     }
 
+    #[test]
+    fn library_not_provided() {
+        let library: Option<NoLibrary> = None;
+        let database = Some(MockIDatabase::new());
+        let mut music_hoard = MusicHoard::new(library, database);
+
+        let actual_err = music_hoard.rescan_library().unwrap_err();
+        let expected_err = Error::LibraryError(String::from("library not provided"));
+
+        assert_eq!(actual_err, expected_err);
+    }
+
     #[test]
     fn library_error() {
         let mut library = MockILibrary::new();
@@ -983,6 +995,23 @@ mod tests {
         assert_eq!(actual_err.to_string(), expected_err.to_string());
     }
 
+    #[test]
+    fn database_not_provided() {
+        let library = Some(MockILibrary::new());
+        let database: Option<NoDatabase> = None;
+        let mut music_hoard = MusicHoard::new(library, database);
+
+        let expected_err = Error::DatabaseError(String::from("database not provided"));
+
+        let actual_err = music_hoard.load_from_database().unwrap_err();
+        assert_eq!(actual_err, expected_err);
+        assert_eq!(actual_err.to_string(), expected_err.to_string());
+
+        let actual_err = music_hoard.save_to_database().unwrap_err();
+        assert_eq!(actual_err, expected_err);
+        assert_eq!(actual_err.to_string(), expected_err.to_string());
+    }
+
     #[test]
     fn database_load_error() {
         let library = MockILibrary::new();
diff --git a/src/library/mod.rs b/src/library/mod.rs
index 3e4ce7d..e94ef94 100644
--- a/src/library/mod.rs
+++ b/src/library/mod.rs
@@ -17,6 +17,15 @@ pub trait ILibrary {
     fn list(&mut self, query: &Query) -> Result<Vec<Item>, Error>;
 }
 
+/// Non-implementation defined to make generics easier.
+pub struct NoLibrary {}
+
+impl ILibrary for NoLibrary {
+    fn list(&mut self, _query: &Query) -> Result<Vec<Item>,Error> {
+        panic!()
+    }
+}
+
 /// An item from the library. An item corresponds to an individual file (usually a single track).
 #[derive(Debug, PartialEq, Eq, Hash)]
 pub struct Item {
@@ -127,7 +136,14 @@ impl From<Utf8Error> for Error {
 mod tests {
     use std::io;
 
-    use super::{Error, Field, Query};
+    use super::{Error, Field, Query, NoLibrary, ILibrary};
+
+    #[test]
+    #[should_panic]
+    fn no_library_list() {
+        let mut library = NoLibrary {};
+        _ = library.list(&Query::default());
+    }
 
     #[test]
     fn query() {