DB - Add tests for ALTER TABLE w/ transaction

src/db/table/core/row.rs

@@ -5,7 +5,7 @@ use std::ops::{Deref, DerefMut};
 #[repr(transparent)]
 pub struct Row(pub Vec<Value>);
 
-#[derive(Debug)]
+#[derive(Debug, PartialEq, Clone)]
 pub struct RowStack {
     pub stack: Vec<Row>,
 }
@@ -27,4 +27,12 @@ impl RowStack {
     pub fn new(stack: Row) -> Self {
         Self { stack: vec![stack] }
     }
+
+    pub fn new_with_stack(stack: Vec<Row>) -> Self {
+        Self { stack }
+    }
+
+    pub fn append_clone(&mut self) {
+        self.stack.push(self.stack.last().unwrap().clone());
+    }
 }

src/db/table/core/table.rs

@@ -73,6 +73,15 @@ impl Table {
             .collect()
     }
 
+    pub fn get_row_stacks_mut(&mut self) -> Vec<&mut RowStack> {
+        self.rows.iter_mut().collect()
+    }
+
+    #[cfg(test)]
+    pub fn get_row_stacks_clone(&self) -> Vec<RowStack> {
+        self.rows.clone()
+    }
+
     pub fn set_rows(&mut self, rows: Vec<Row>) {
         self.rows = rows.into_iter().map(|r| RowStack::new(r)).collect();
     }

src/db/table/operations/alter_table/mod.rs

@@ -40,6 +40,11 @@ pub fn alter_table(
                 ));
             }
             table.push_column(column_def);
+            if is_transaction {
+                table.get_row_stacks_mut().iter_mut().for_each(|row_stack| {
+                    row_stack.append_clone();
+                });
+            }
             table.get_rows_mut().iter_mut().for_each(|row| {
                 row.push(Value::Null);
             });
@@ -59,7 +64,11 @@ pub fn alter_table(
                 .drop_column(&column_name, &table.name, is_transaction)?;
             // This is kind of bad because it's an O(n^2) operation however SQLite
             // preserves the order of the columns after drop column statements.
-
+            if is_transaction {
+                table.get_row_stacks_mut().iter_mut().for_each(|row_stack| {
+                    row_stack.append_clone();
+                });
+            }
             table.get_rows_mut().iter_mut().for_each(|row| {
                 row.remove(index);
             });
@@ -71,7 +80,11 @@ pub fn alter_table(
 #[cfg(test)]
 mod tests {
     use super::*;
-    use crate::db::table::core::{column::ColumnDefinition, row::Row, value::DataType};
+    use crate::db::table::core::{
+        column::ColumnDefinition,
+        row::{Row, RowStack},
+        value::DataType,
+    };
     use crate::db::table::test_utils::default_database;
 
     #[test]
@@ -270,5 +283,57 @@ mod tests {
                     .collect::<Vec<String>>())
                 .collect::<Vec<Vec<String>>>()
         );
+
+        let expected_row_stacks = vec![
+            RowStack::new_with_stack(vec![
+                Row(vec![
+                    Value::Integer(1),
+                    Value::Text("John".to_string()),
+                    Value::Integer(25),
+                    Value::Real(1000.0),
+                ]),
+                Row(vec![
+                    Value::Integer(1),
+                    Value::Text("John".to_string()),
+                    Value::Real(1000.0),
+                ]),
+            ]),
+            RowStack::new_with_stack(vec![
+                Row(vec![
+                    Value::Integer(2),
+                    Value::Text("Jane".to_string()),
+                    Value::Integer(30),
+                    Value::Real(2000.0),
+                ]),
+                Row(vec![
+                    Value::Integer(2),
+                    Value::Text("Jane".to_string()),
+                    Value::Real(2000.0),
+                ]),
+            ]),
+            RowStack::new_with_stack(vec![
+                Row(vec![
+                    Value::Integer(3),
+                    Value::Text("Jim".to_string()),
+                    Value::Integer(35),
+                    Value::Real(3000.0),
+                ]),
+                Row(vec![
+                    Value::Integer(3),
+                    Value::Text("Jim".to_string()),
+                    Value::Real(3000.0),
+                ]),
+            ]),
+            RowStack::new_with_stack(vec![
+                Row(vec![
+                    Value::Integer(4),
+                    Value::Null,
+                    Value::Integer(40),
+                    Value::Real(4000.0),
+                ]),
+                Row(vec![Value::Integer(4), Value::Null, Value::Real(4000.0)]),
+            ]),
+        ];
+        assert_eq!(expected_row_stacks, table.get_row_stacks_clone());
     }
 }