Revalidate unique-index point reads

codegen/src/generators/in_memory/table/index_fns.rs

@@ -63,7 +63,9 @@ impl InMemoryGenerator {
         let type_ = columns_map.get(i).ok_or(syn::Error::new(i.span(), "Row not found"))?;
         let fn_name = Ident::new(format!("select_by_{i}").as_str(), Span::mixed_site());
         let field_ident = &idx.name;
-        let by = if is_float(type_.to_string().as_str()) {
+        let row_field_ident = &idx.field;
+        let is_float = is_float(type_.to_string().as_str());
+        let by = if is_float {
             quote! {
                 &OrderedFloat(by)
             }
@@ -72,11 +74,21 @@ impl InMemoryGenerator {
                 &by
             }
         };
+        let predicate_matches = if is_float {
+            quote! {
+                OrderedFloat(row.#row_field_ident).eq(&OrderedFloat(by))
+            }
+        } else {
+            quote! {
+                row.#row_field_ident.eq(&by)
+            }
+        };
 
         Ok(quote! {
             pub fn #fn_name(&self, by: #type_) -> Option<#row_ident> {
                 let link: Link = self.0.indexes.#field_ident.get(#by).map(|kv| kv.get().value.into())?;
-                self.0.data.select_non_ghosted(link).ok()
+                let row = self.0.data.select_non_ghosted(link).ok()?;
+                #predicate_matches.then_some(row)
             }
         })
     }

codegen/src/generators/persist/table/index_fns.rs

@@ -63,7 +63,9 @@ impl PersistGenerator {
         let type_ = columns_map.get(i).ok_or(syn::Error::new(i.span(), "Row not found"))?;
         let fn_name = Ident::new(format!("select_by_{i}").as_str(), Span::mixed_site());
         let field_ident = &idx.name;
-        let by = if is_float(type_.to_string().as_str()) {
+        let row_field_ident = &idx.field;
+        let is_float = is_float(type_.to_string().as_str());
+        let by = if is_float {
             quote! {
                 &OrderedFloat(by)
             }
@@ -72,11 +74,21 @@ impl PersistGenerator {
                 &by
             }
         };
+        let predicate_matches = if is_float {
+            quote! {
+                OrderedFloat(row.#row_field_ident).eq(&OrderedFloat(by))
+            }
+        } else {
+            quote! {
+                row.#row_field_ident.eq(&by)
+            }
+        };
 
         Ok(quote! {
             pub fn #fn_name(&self, by: #type_) -> Option<#row_ident> {
                 let link: Link = self.0.indexes.#field_ident.get(#by).map(|kv| kv.get().value.into())?;
-                self.0.data.select_non_ghosted(link).ok()
+                let row = self.0.data.select_non_ghosted(link).ok()?;
+                #predicate_matches.then_some(row)
             }
         })
     }

codegen/src/generators/read_only/table/index_fns.rs

@@ -63,7 +63,9 @@ impl ReadOnlyGenerator {
         let type_ = columns_map.get(i).ok_or(syn::Error::new(i.span(), "Row not found"))?;
         let fn_name = Ident::new(format!("select_by_{i}").as_str(), Span::mixed_site());
         let field_ident = &idx.name;
-        let by = if is_float(type_.to_string().as_str()) {
+        let row_field_ident = &idx.field;
+        let is_float = is_float(type_.to_string().as_str());
+        let by = if is_float {
             quote! {
                 &OrderedFloat(by)
             }
@@ -72,11 +74,21 @@ impl ReadOnlyGenerator {
                 &by
             }
         };
+        let predicate_matches = if is_float {
+            quote! {
+                OrderedFloat(row.#row_field_ident).eq(&OrderedFloat(by))
+            }
+        } else {
+            quote! {
+                row.#row_field_ident.eq(&by)
+            }
+        };
 
         Ok(quote! {
             pub fn #fn_name(&self, by: #type_) -> Option<#row_ident> {
                 let link: Link = self.0.indexes.#field_ident.get(#by).map(|kv| kv.get().value.into())?;
-                self.0.data.select_non_ghosted(link).ok()
+                let row = self.0.data.select_non_ghosted(link).ok()?;
+                #predicate_matches.then_some(row)
             }
         })
     }

tests/worktable/float.rs

@@ -16,6 +16,44 @@ worktable! (
     }
 );
 
+worktable! (
+    name: TestUniqueFloat,
+    columns: {
+        id: u64 primary_key autoincrement,
+        value: f64,
+    },
+    indexes: {
+        value_idx: value unique,
+    }
+);
+
+#[test]
+fn unique_float_point_read_revalidates_the_returned_row() {
+    let table = TestUniqueFloatWorkTable::default();
+    let first = TestUniqueFloatRow {
+        id: table.get_next_pk().into(),
+        value: 1.5,
+    };
+    let second = TestUniqueFloatRow {
+        id: table.get_next_pk().into(),
+        value: 2.5,
+    };
+    table.insert(first.clone()).unwrap();
+    table.insert(second.clone()).unwrap();
+
+    let second_link = table
+        .0
+        .primary_index
+        .pk_map
+        .get(&TestUniqueFloatPrimaryKey(second.id))
+        .map(|entry| entry.get().value.0)
+        .unwrap();
+    TableIndex::insert(&table.0.indexes.value_idx, OrderedFloat(first.value), second_link);
+
+    assert!(table.select_by_value(first.value).is_none());
+    assert_eq!(table.select_by_value(second.value), Some(second));
+}
+
 #[test]
 fn select_all_range_float_test() {
     let table = TestFloatWorkTable::default();

tests/worktable/index/insert.rs

@@ -38,6 +38,44 @@ async fn insert() {
     assert!(table.select(2).is_none())
 }
 
+#[test]
+fn unique_point_read_revalidates_the_returned_row() {
+    let table = TestWorkTable::default();
+    let first = TestRow {
+        id: table.get_next_pk().into(),
+        val: 13,
+        attr1: "first".to_string(),
+        attr2: -128,
+        attr3: 1,
+        attr4: "first-unique".to_string(),
+    };
+    let second = TestRow {
+        id: table.get_next_pk().into(),
+        val: 14,
+        attr1: "second".to_string(),
+        attr2: 128,
+        attr3: 2,
+        attr4: "second-unique".to_string(),
+    };
+    table.insert(first.clone()).unwrap();
+    table.insert(second.clone()).unwrap();
+
+    let second_link = table
+        .0
+        .primary_index
+        .pk_map
+        .get(&TestPrimaryKey(second.id))
+        .map(|entry| entry.get().value.0)
+        .unwrap();
+
+    // Model the transient state where a unique-index entry still names a row
+    // whose indexed field has already changed.
+    TableIndex::insert(&table.0.indexes.attr2_idx, first.attr2, second_link);
+
+    assert!(table.select_by_attr2(first.attr2).is_none());
+    assert_eq!(table.select_by_attr2(second.attr2), Some(second));
+}
+
 #[tokio::test]
 async fn insert_when_pk_exists() {
     let table = TestWorkTable::default();