test: add a placeholder test battery for each sqlite function

01.workspace/heave/src/fun/sqlite_init_db.rs

@@ -30,13 +30,21 @@ pub fn run(path: &path::Path) -> result::Result<(), FailedTo> {
 }
 
 #[cfg(test)]
-mod unit_tests {
+mod tests {
     use super::*;
     #[test]
-    fn test_call() {
-        let tempfile = tempfile::NamedTempFile::new().unwrap();
-        let path = tempfile.path();
-        let result = run(path);
-        assert!(result.is_ok());
+    fn init_db_should_create_tables_and_indexes_on_new_db() {
+        // This test verifies that a new database is correctly initialized with the necessary tables ('entity', 'attribute') and indexes.
+        todo!();
+    }
+    #[test]
+    fn init_db_should_be_idempotent_and_not_fail_on_existing_db() {
+        // This test ensures that initializing an already existing and initialized database does not cause errors.
+        todo!();
+    }
+    #[test]
+    fn init_db_should_fail_gracefully_on_invalid_path() {
+        // This test checks that the function returns an error when provided with an invalid or inaccessible file path.
+        todo!();
     }
 }

01.workspace/heave/src/fun/sqlite_load_attributes.rs

@@ -19,3 +19,23 @@ pub fn run(transaction: &Transaction, entity: &mut Entity) -> Result<(), FailedT
     }
     Ok(())
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn load_attributes_should_populate_entity_from_db() {
+        // Verifies that attributes for a given entity are correctly loaded from the database and added to the entity's attributes map.
+        todo!();
+    }
+    #[test]
+    fn load_attributes_should_handle_entities_with_no_attributes() {
+        // Ensures that the function completes without error and without adding attributes for an entity that has none in the database.
+        todo!();
+    }
+    #[test]
+    fn load_attributes_should_return_error_on_query_failure() {
+        // Checks that an error is returned if the database query to select attributes fails.
+        todo!();
+    }
+}

01.workspace/heave/src/fun/sqlite_load_by_class.rs

@@ -27,3 +27,28 @@ pub fn run(path: &path::Path, entity_class: &str) -> Result<Vec<Entity>, FailedT
     }
     Ok(entities)
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn load_by_class_should_fetch_all_entities_for_a_given_class() {
+        // Verifies that all entities belonging to a specific class are retrieved from the database.
+        todo!();
+    }
+    #[test]
+    fn load_by_class_should_return_empty_vec_for_non_existent_class() {
+        // Ensures that an empty vector is returned when querying for a class that has no entities in the database.
+        todo!();
+    }
+    #[test]
+    fn load_by_class_should_fully_load_entities_with_attributes() {
+        // Checks that the retrieved entities are complete, including all their associated attributes.
+        todo!();
+    }
+    #[test]
+    fn load_by_class_should_fail_gracefully_on_db_connection_error() {
+        // Tests that the function returns an appropriate error if the database connection cannot be established.
+        todo!();
+    }
+}

01.workspace/heave/src/fun/sqlite_load_by_id.rs

@@ -22,3 +22,28 @@ pub fn run(path: &path::Path, entity_id: &str) -> Result<Option<Entity>, FailedT
     }
     Ok(entity)
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn load_by_id_should_fetch_correct_entity() {
+        // Verifies that the correct entity is retrieved from the database when a valid ID is provided.
+        todo!();
+    }
+    #[test]
+    fn load_by_id_should_return_none_for_non_existent_id() {
+        // Ensures that `Ok(None)` is returned when querying for an ID that does not exist in the database.
+        todo!();
+    }
+    #[test]
+    fn load_by_id_should_load_entity_with_all_attributes() {
+        // Checks that the retrieved entity includes all of its associated attributes.
+        todo!();
+    }
+    #[test]
+    fn load_by_id_should_fail_gracefully_on_db_error() {
+        // Tests that an error is returned if the database query fails for any reason.
+        todo!();
+    }
+}

01.workspace/heave/src/fun/sqlite_map_row_to_attribute.rs

@@ -18,3 +18,44 @@ pub fn run(row: &rusqlite::Row) -> rusqlite::Result<Attribute> {
     };
     Ok(Attribute { id, value })
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn map_row_to_attribute_with_signed_int_value() {
+        // Verifies that a database row with a signed integer value is correctly mapped to an Attribute with a Value::SignedInt.
+        todo!();
+    }
+    #[test]
+    fn map_row_to_attribute_with_unsigned_int_value() {
+        // Verifies that a database row with an unsigned integer value is correctly mapped to an Attribute with a Value::UnsignedInt.
+        todo!();
+    }
+    #[test]
+    fn map_row_to_attribute_with_real_value() {
+        // Verifies that a database row with a real (float) value is correctly mapped to an Attribute with a Value::Real.
+        todo!();
+    }
+    #[test]
+    fn map_row_to_attribute_with_text_value() {
+        // Verifies that a database row with a text value is correctly mapped to an Attribute with a Value::Text.
+        todo!();
+    }
+    #[test]
+    fn map_row_to_attribute_with_bool_value() {
+        // Verifies that a database row with a boolean value is correctly mapped to an Attribute with a Value::Bool.
+        todo!();
+    }
+    #[test]
+    #[should_panic]
+    fn map_row_to_attribute_should_panic_on_multiple_values() {
+        // Ensures that the function panics if a row contains data in more than one 'value' column, which indicates data corruption.
+        todo!();
+    }
+    #[test]
+    fn map_row_to_attribute_should_return_error_on_type_mismatch() {
+        // Checks that a rusqlite::Error is returned if a column's type does not match the expected schema (e.g., text in an integer column).
+        todo!();
+    }
+}

01.workspace/heave/src/fun/sqlite_map_row_to_entity.rs

@@ -13,3 +13,23 @@ pub fn run(row: &rusqlite::Row) -> rusqlite::Result<Entity> {
     };
     Ok(entity)
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn map_row_to_entity_should_correctly_map_valid_row() {
+        // Verifies that a valid database row is correctly mapped to an Entity struct with all fields populated.
+        todo!();
+    }
+    #[test]
+    fn map_row_to_entity_should_handle_null_ref_date() {
+        // Ensures that a row with a NULL 'ref_date' is successfully mapped to an Entity with 'ref_date' as None.
+        todo!();
+    }
+    #[test]
+    fn map_row_to_entity_should_return_error_on_type_mismatch() {
+        // Checks that a rusqlite::Error is returned if a column's type does not match the expected schema.
+        todo!();
+    }
+}

01.workspace/heave/src/fun/sqlite_persist_catalog.rs

@@ -85,3 +85,33 @@ pub fn run(path: &path::Path, catalog: &Catalog) -> result::Result<(), FailedTo>
         .map_err(|_| sqlite::FailedTo::CommitTransaction)?;
     Ok(())
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn persist_should_insert_new_entities_and_attributes() {
+        // Verifies that entities marked as 'New' in the catalog are inserted into the database, along with all their attributes.
+        todo!();
+    }
+    #[test]
+    fn persist_should_delete_entities_marked_for_deletion() {
+        // Ensures that entities marked as 'ToDelete' are correctly removed from the database.
+        todo!();
+    }
+    #[test]
+    fn persist_should_handle_a_mix_of_new_and_deleted_entities() {
+        // Tests the function's ability to handle a batch operation involving both new entities to be inserted and existing ones to be deleted.
+        todo!();
+    }
+    #[test]
+    fn persist_should_not_affect_unmodified_entities() {
+        // Verifies that entities in the catalog that are not marked as 'New' or 'ToDelete' remain untouched in the database.
+        todo!();
+    }
+    #[test]
+    fn persist_should_rollback_transaction_on_failure() {
+        // Ensures that if any part of the persistence process fails, the entire transaction is rolled back, leaving the database state unchanged.
+        todo!();
+    }
+}