Moved record to data.

src/data/id.rs

@@ -0,0 +1,37 @@
+use std::fmt;
+use uuid::Uuid;
+
+#[derive(Clone)]
+pub struct ID {
+    data: Uuid,
+}
+
+impl ID {
+    pub fn new() -> Self {
+        Self {
+            data: Uuid::new_v4(),
+        }
+    }
+}
+
+impl fmt::Display for ID {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}", self.data)
+    }
+}
+
+#[cfg(test)]
+mod id {
+    use super::*;
+
+    #[test]
+    fn id_are_unique() {
+        let mut ids: Vec<String> = Vec::new();
+        for _ in 1..10 {
+            let id = ID::new();
+            let id_string = id.to_string();
+            assert!(!ids.contains(&id_string), "'{}' repeated", id_string);
+            ids.push(id_string);
+        }
+    }
+}

src/data/mod.rs

@@ -0,0 +1,66 @@
+mod id;
+
+use id::ID;
+use std::{collections::HashMap, fmt};
+
+#[derive(Clone)]
+enum Field {
+    ID(ID),
+}
+
+struct Record {
+    data: HashMap<String, Field>,
+}
+
+impl Record {
+    fn new(data: HashMap<String, Field>) -> Self {
+        Self { data: data }
+    }
+
+    fn len(&self) -> usize {
+        self.data.len()
+    }
+
+    fn get(&self, name: &str) -> Field {
+        match self.data.get(name) {
+            Some(data) => data.clone(),
+            None => unreachable!(),
+        }
+    }
+}
+
+impl fmt::Display for Field {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            Field::ID(id) => write!(f, "{}", id),
+        }
+    }
+}
+
+#[cfg(test)]
+mod records {
+    use super::*;
+
+    #[test]
+    fn new_record() {
+        let data: HashMap<String, Field> = HashMap::new();
+        let rec = Record::new(data);
+        assert_eq!(rec.len(), 0);
+    }
+
+    #[test]
+    fn new_record_more_data() {
+        let a = ID::new();
+        let b = ID::new();
+        let c = ID::new();
+        let mut data: HashMap<String, Field> = HashMap::new();
+        data.insert("a".to_string(), Field::ID(a.clone()));
+        data.insert("b".to_string(), Field::ID(b.clone()));
+        data.insert("c".to_string(), Field::ID(c.clone()));
+        let rec = Record::new(data);
+        assert_eq!(rec.len(), 3);
+        assert_eq!(rec.get("a").to_string(), a.to_string(), "record a");
+        assert_eq!(rec.get("b").to_string(), b.to_string(), "record b");
+        assert_eq!(rec.get("c").to_string(), c.to_string(), "record c");
+    }
+}