test: add intended use tests to try/demo the library

01.workspace/heave/src/tst/intended_use.rs

@@ -0,0 +1,24 @@
+#[cfg(test)]
+mod tests {
+    use crate::*;
+    #[test]
+    fn check_001() {
+        // Demonstrates the costruction of a new entity instance
+        let _product = Entity::new("product")
+            .with_attribute("name", "laptop")
+            .with_attribute("price", 200000u64)
+            .with_attribute("discount", 2.5f64)
+            .with_attribute("in_stock", true);
+    }
+    #[test]
+    fn check_002() {
+        // Demonstrate attribute value reading
+        let product = Entity::new("product")
+            .with_attribute("name", "laptop")
+            .with_attribute("price", 200000u64);
+        let name = product.value_of("name");
+        let price = product.value_of("price");
+        assert_eq!(name, Some(&Value::Text(String::from("laptop"))));
+        assert_eq!(price, Some(&Value::UnsignedInt(200000)));
+    }
+}

01.workspace/heave/src/tst/mod.rs

@@ -1,2 +1,3 @@
 pub mod entity_new;
 pub mod entity_with_attribute;
+pub mod intended_use;