From fdfdaa9fc02a6db5d91de6bbc4b1da3fc1a39e4d Mon Sep 17 00:00:00 2001
From: Yuriy Dupyn <2153100+omedusyo@users.noreply.github.com>
Date: Sat, 27 Jan 2024 23:42:03 +0100
Subject: [PATCH] Return table schema in SELECT response

---
 minisql/src/interpreter.rs | 30 +++++++++++++++---------------
 1 file changed, 15 insertions(+), 15 deletions(-)

diff --git a/minisql/src/interpreter.rs b/minisql/src/interpreter.rs
index b96dc40..dd0e870 100644
--- a/minisql/src/interpreter.rs
+++ b/minisql/src/interpreter.rs
@@ -18,7 +18,7 @@ pub struct State {
 
 // #[derive(Debug)]
 pub enum Response<'a> {
-    Selected(Box<dyn Iterator<Item=Row> + 'a + Send>),
+    Selected(&'a TableSchema, Box<dyn Iterator<Item=Row> + 'a + Send>),
     Inserted,
     Deleted(usize), // how many were deleted
     TableCreated,
@@ -31,7 +31,7 @@ impl std::fmt::Debug for Response<'_> {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> Result<(), std::fmt::Error> {
         use Response::*;
         match self {
-            Selected(_rows) =>
+            Selected(_schema, _rows) =>
                 // TODO: How can we iterate through the rows without having to take ownership of
                 // them?
                 f.write_str("Some rows... trust me"),
@@ -104,7 +104,7 @@ impl State {
                     }
                 };
 
-                Ok(Response::Selected(selected_rows))
+                Ok(Response::Selected(table.schema(), selected_rows))
             },
             Insert(table_position, values) => {
                 let table: &mut Table = self.table_at_mut(table_position);
@@ -195,8 +195,8 @@ mod tests {
         let response: Response = state
             .interpret(Operation::Select(users_position, users_schema.all_selection(), None))
             .unwrap();
-        assert!(matches!(response, Response::Selected(_)));
-        let Response::Selected(rows) = response else {
+        assert!(matches!(response, Response::Selected(_, _)));
+        let Response::Selected(_schema, rows) = response else {
             panic!()
         };
         let rows: Vec<_> = rows.collect();
@@ -237,8 +237,8 @@ mod tests {
             .interpret(Operation::Select(users, users_schema.all_selection(), None))
             .unwrap();
 
-        assert!(matches!(response, Response::Selected(_)));
-        let Response::Selected(rows) = response else {
+        assert!(matches!(response, Response::Selected(_, _)));
+        let Response::Selected(_schema, rows) = response else {
             panic!()
         };
         let rows: Vec<_> = rows.collect();
@@ -304,8 +304,8 @@ mod tests {
         {
             let response: Response = state.interpret(Select(users_position, users_schema.all_selection(), None)).unwrap();
 
-            assert!(matches!(response, Response::Selected(_)));
-            let Response::Selected(rows) = response else {
+            assert!(matches!(response, Response::Selected(_, _)));
+            let Response::Selected(_schema, rows) = response else {
                 panic!()
             };
         let rows: Vec<_> = rows.collect();
@@ -332,8 +332,8 @@ mod tests {
                     Some(Eq(id_column, id0.clone())),
                 ))
                 .unwrap();
-            assert!(matches!(response, Response::Selected(_)));
-            let Response::Selected(rows) = response else {
+            assert!(matches!(response, Response::Selected(_, _)));
+            let Response::Selected(_schema, rows) = response else {
                 panic!()
             };
             let rows: Vec<_> = rows.collect();
@@ -354,8 +354,8 @@ mod tests {
                     Some(Eq(id_column, id0.clone())),
                 ))
                 .unwrap();
-            assert!(matches!(response, Response::Selected(_)));
-            let Response::Selected(rows) = response else {
+            assert!(matches!(response, Response::Selected(_, _)));
+            let Response::Selected(_schema, rows) = response else {
                 panic!()
             };
             let rows: Vec<_> = rows.collect();
@@ -429,8 +429,8 @@ mod tests {
 
         let response: Response = state.interpret(Select(users_position, users_schema.all_selection(), None)).unwrap();
 
-        assert!(matches!(response, Response::Selected(_)));
-        let Response::Selected(rows) = response else {
+        assert!(matches!(response, Response::Selected(_, _)));
+        let Response::Selected(_schema, rows) = response else {
             panic!()
         };
         let rows: Vec<_> = rows.collect();