Row: it can now be iterated (#106)

* Initial row iter() implementation

* Added a test

* Moved .iter() into the correct impl block

* Added column_names to Row

* Return columns in the correct order when iterating on a Row

* Ran cargo clippy --fix

* Hopefully address PR comments

* Address PR comments, part two

src/cursor.rs

@@ -24,6 +24,7 @@ pub struct CursorWithOwnership<'l> {
 /// A row.
 #[derive(Debug)]
 pub struct Row {
+    column_names: Rc<Vec<String>>,
     column_mapping: Rc<HashMap<String, usize>>,
     values: Vec<Value>,
 }
@@ -107,6 +108,7 @@ macro_rules! implement(
                 match self.try_next() {
                     Ok(value) => {
                         value.map(|values| Ok(Row {
+                            column_names: self.statement.column_names.clone(),
                             column_mapping: self.statement.column_mapping(),
                             values,
                         }))
@@ -186,6 +188,15 @@ impl Row {
         }
         T::try_from(&self.values[column.index(self)])
     }
+
+    pub fn iter(&self) -> impl Iterator<Item = (&'_ str, &'_ Value)> + use<'_> {
+        self.column_names.iter().map(|column_name| {
+            (
+                column_name.as_str(),
+                &self.values[self.column_mapping[column_name]],
+            )
+        })
+    }
 }
 
 impl From<Row> for Vec<Value> {

src/statement.rs

@@ -20,7 +20,7 @@ macro_rules! transient(
 /// A prepared statement.
 pub struct Statement<'l> {
     raw: (*mut ffi::sqlite3_stmt, *mut ffi::sqlite3),
-    column_names: Vec<String>,
+    pub(crate) column_names: Rc<Vec<String>>,
     column_mapping: Rc<HashMap<String, usize>>,
     phantom: PhantomData<(ffi::sqlite3_stmt, &'l ffi::sqlite3)>,
 }
@@ -271,7 +271,7 @@ impl<'l> Statement<'l> {
     }
 }
 
-impl<'l> Drop for Statement<'l> {
+impl Drop for Statement<'_> {
     #[inline]
     fn drop(&mut self) {
         unsafe { ffi::sqlite3_finalize(self.raw.0) };
@@ -603,7 +603,7 @@ where
         .collect();
     Ok(Statement {
         raw: (raw_statement, raw_connection),
-        column_names,
+        column_names: Rc::new(column_names),
         column_mapping: Rc::new(column_mapping),
         phantom: PhantomData,
     })

tests/cursor.rs

@@ -241,6 +241,46 @@ fn try_next_try_into() {
     assert!((&row[4]).try_into::<&str>().is_err());
 }
 
+#[test]
+fn row_can_be_iterated() {
+    let connection = setup_users(":memory:");
+    let query = "SELECT * FROM users";
+    let mut statement = ok!(connection.prepare(query));
+    let mut cursor = statement.iter();
+    let row = ok!(ok!(cursor.next()));
+    let _ = row.iter();
+}
+
+#[test]
+fn iterating_row_yields_all_items() {
+    let connection = setup_users(":memory:");
+    let query = "SELECT * FROM users";
+    let mut statement = ok!(connection.prepare(query));
+    let mut cursor = statement.iter();
+    let row = ok!(ok!(cursor.next()));
+    let row = row.iter();
+    assert_eq!(5, row.count());
+}
+
+#[test]
+fn iterating_row_yields_all_items_in_correct_order() {
+    let connection = setup_users(":memory:");
+    let query = "SELECT * FROM users";
+    let mut statement = ok!(connection.prepare(query));
+    let mut cursor = statement.iter();
+    let row = ok!(ok!(cursor.next()));
+    let mut row = row.iter();
+    assert_eq!(Some(("id", &Value::Integer(1))), row.next());
+    assert_eq!(
+        Some(("name", &Value::String("Alice".to_owned()))),
+        row.next()
+    );
+    assert_eq!(Some(("age", &Value::Float(42.69))), row.next());
+    assert_eq!(Some(("photo", &Value::Binary(vec![66, 105]))), row.next());
+    assert_eq!(Some(("email", &Value::Null)), row.next());
+    assert_eq!(None, row.next());
+}
+
 #[test]
 fn workflow() {
     let connection = setup_users(":memory:");

tests/statement.rs

@@ -254,7 +254,7 @@ fn workflow_1() {
         statement: Statement<'l>,
     }
 
-    impl<'l> Database<'l> {
+    impl Database<'_> {
         fn run_once(&mut self) -> sqlite::Result<()> {
             self.statement.reset()?;
             self.statement.bind((":age", 40))?;
@@ -269,7 +269,7 @@ fn workflow_1() {
 
     let mut database = Database {
         connection: &connection,
-        statement: statement,
+        statement,
     };
 
     for _ in 0..5 {