feat(psl): add warning when SetDefault is used on mysql with `rel…

…ationMode = "foreignKeys"` (#3435)

* feat(psl): support connector-specific warnings in DatamodelWarning

* feat(psl): add warning when SetDefault is used in MySQL with foreignKeys mode active

* test(psl): add tests for SetDefault warning on MySQL

* test: add introspection and migration tests for SetDefault warning on MySQL

* chore: removed deprecated previewFeature referentialIntegrity

* chore: fix snapshots in unit tests

* test: exclude Vitess from "introspect_set_default_should_warn" test

* chore: simplify conditional for SetDefault

introspection-engine/introspection-engine-tests/tests/referential_actions/mod.rs

@@ -1,4 +1,5 @@
 mod cockroachdb;
+mod mysql;
 mod sqlite;
 
 use barrel::types;

introspection-engine/introspection-engine-tests/tests/referential_actions/mysql.rs

@@ -0,0 +1,77 @@
+use introspection_engine_tests::test_api::*;
+
+// Older versions of MySQL (5.6+) raise a syntax error on `CREATE TABLE` declarations with `SET DEFAULT` referential actions,
+// so we can skip introspecting those. MariaDb 10.0 suffers from the same issue.
+// We should see validation warnings on MySQL 8+.
+#[test_connector(tags(Mysql8), exclude(Vitess))]
+async fn introspect_set_default_should_warn(api: &TestApi) -> TestResult {
+    let setup = r#"
+      CREATE TABLE `SomeUser` (
+          `id` INTEGER NOT NULL AUTO_INCREMENT,
+      
+          PRIMARY KEY (`id`)
+      ) DEFAULT CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
+      
+      CREATE TABLE `Post` (
+          `id` INTEGER NOT NULL AUTO_INCREMENT,
+          `userId` INTEGER NULL DEFAULT 3,
+      
+          PRIMARY KEY (`id`)
+      ) DEFAULT CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
+      
+      ALTER TABLE `Post` ADD CONSTRAINT `Post_userId_fkey`
+        FOREIGN KEY (`userId`) REFERENCES `SomeUser`(`id`)
+        ON DELETE SET DEFAULT ON UPDATE SET DEFAULT;
+    "#;
+
+    api.raw_cmd(setup).await;
+
+    let expected_schema = expect![[r#"
+        generator client {
+          provider = "prisma-client-js"
+        }
+
+        datasource db {
+          provider = "mysql"
+          url      = "env(TEST_DATABASE_URL)"
+        }
+
+        model Post {
+          id       Int       @id @default(autoincrement())
+          userId   Int?      @default(3)
+          SomeUser SomeUser? @relation(fields: [userId], references: [id], onDelete: SetDefault, onUpdate: SetDefault)
+
+          @@index([userId], map: "Post_userId_fkey")
+        }
+
+        model SomeUser {
+          id   Int    @id @default(autoincrement())
+          Post Post[]
+        }
+    "#]];
+
+    expected_schema.assert_eq(&api.introspect().await?);
+    let schema = psl::parse_schema(expected_schema.data())?;
+
+    let warning_messages = schema
+        .diagnostics
+        .warnings_to_pretty_string("schema.prisma", &schema.db.source());
+
+    let expected_validation = expect![[r#"
+        warning: Using SetDefault on MySQL may yield to unexpected results, as the database will silently change the referential action to `NoAction`.
+          -->  schema.prisma:14
+           | 
+        13 |           userId   Int?      @default(3)
+        14 |           SomeUser SomeUser? @relation(fields: [userId], references: [id], onDelete: SetDefault, onUpdate: SetDefault)
+           | 
+        warning: Using SetDefault on MySQL may yield to unexpected results, as the database will silently change the referential action to `NoAction`.
+          -->  schema.prisma:14
+           | 
+        13 |           userId   Int?      @default(3)
+        14 |           SomeUser SomeUser? @relation(fields: [userId], references: [id], onDelete: SetDefault, onUpdate: SetDefault)
+           | 
+    "#]];
+    expected_validation.assert_eq(&warning_messages);
+
+    Ok(())
+}

migration-engine/migration-engine-tests/tests/migrations/relations.rs

@@ -573,7 +573,8 @@ fn on_delete_referential_actions_should_work(api: TestApi) {
 }
 
 // 5.6 and 5.7 doesn't let you `SET DEFAULT` without setting the default value
-// (even if nullable). Maria will silently just use `RESTRICT` instead.
+// (even if nullable). MySQL 8.0+ & MariaDB 10.0 allow you to create a table with
+// `SET DEFAULT`, but will silently use `NO ACTION` / `RESTRICT` instead.
 #[test_connector(exclude(Mysql56, Mysql57, Mariadb, Mssql, Vitess, CockroachDb))]
 fn on_delete_set_default_should_work(api: TestApi) {
     let dm = r#"
@@ -661,7 +662,8 @@ fn on_update_referential_actions_should_work(api: TestApi) {
 }
 
 // 5.6 and 5.7 doesn't let you `SET DEFAULT` without setting the default value
-// (even if nullable). Maria will silently just use `RESTRICT` instead.
+// (even if nullable). MySQL 8.0+ & MariaDB 10.0 allow you to create a table with
+// `SET DEFAULT`, but will silently use `NO ACTION` / `RESTRICT` instead.
 #[test_connector(exclude(Mysql56, Mysql57, Mariadb, Mssql, Vitess, CockroachDb))]
 fn on_update_set_default_should_work(api: TestApi) {
     let dm = r#"

psl/builtin-connectors/src/cockroach_datamodel_connector.rs

@@ -7,7 +7,8 @@ use enumflags2::BitFlags;
 use lsp_types::{CompletionItem, CompletionItemKind, CompletionList};
 use psl_core::{
     datamodel_connector::{
-        Connector, ConnectorCapability, ConstraintScope, NativeTypeConstructor, NativeTypeInstance, StringFilter,
+        Connector, ConnectorCapability, ConstraintScope, NativeTypeConstructor, NativeTypeInstance, RelationMode,
+        StringFilter,
     },
     diagnostics::{DatamodelError, Diagnostics},
     parser_database::{
@@ -192,7 +193,7 @@ impl Connector for CockroachDatamodelConnector {
         }
     }
 
-    fn validate_model(&self, model: ModelWalker<'_>, diagnostics: &mut Diagnostics) {
+    fn validate_model(&self, model: ModelWalker<'_>, _: RelationMode, diagnostics: &mut Diagnostics) {
         validations::autoincrement_validations(model, diagnostics);
 
         for index in model.indexes() {

psl/builtin-connectors/src/mongodb.rs

@@ -59,7 +59,7 @@ impl Connector for MongoDbDatamodelConnector {
         BitFlags::empty()
     }
 
-    fn validate_model(&self, model: ModelWalker<'_>, errors: &mut Diagnostics) {
+    fn validate_model(&self, model: ModelWalker<'_>, _: RelationMode, errors: &mut Diagnostics) {
         validations::id_must_be_defined(model, errors);
 
         if let Some(pk) = model.primary_key() {

psl/builtin-connectors/src/mssql_datamodel_connector.rs

@@ -7,7 +7,9 @@ use connection_string::JdbcString;
 use enumflags2::BitFlags;
 use lsp_types::{CompletionItem, CompletionItemKind, CompletionList};
 use psl_core::{
-    datamodel_connector::{Connector, ConnectorCapability, ConstraintScope, NativeTypeConstructor, NativeTypeInstance},
+    datamodel_connector::{
+        Connector, ConnectorCapability, ConstraintScope, NativeTypeConstructor, NativeTypeInstance, RelationMode,
+    },
     diagnostics::{Diagnostics, Span},
     parser_database::{self, ast, ParserDatabase, ReferentialAction, ScalarType},
 };
@@ -228,7 +230,12 @@ impl Connector for MsSqlDatamodelConnector {
         }
     }
 
-    fn validate_model(&self, model: parser_database::walkers::ModelWalker<'_>, errors: &mut Diagnostics) {
+    fn validate_model(
+        &self,
+        model: parser_database::walkers::ModelWalker<'_>,
+        _: RelationMode,
+        errors: &mut Diagnostics,
+    ) {
         for index in model.indexes() {
             validations::index_uses_correct_field_types(self, index, errors);
         }

psl/builtin-connectors/src/mysql_datamodel_connector.rs

@@ -5,7 +5,9 @@ pub use native_types::MySqlType;
 
 use enumflags2::BitFlags;
 use psl_core::{
-    datamodel_connector::{Connector, ConnectorCapability, ConstraintScope, NativeTypeConstructor, NativeTypeInstance},
+    datamodel_connector::{
+        Connector, ConnectorCapability, ConstraintScope, NativeTypeConstructor, NativeTypeInstance, RelationMode,
+    },
     diagnostics::{DatamodelError, Diagnostics, Span},
     parser_database::{walkers, ReferentialAction, ScalarType},
 };
@@ -211,14 +213,20 @@ impl Connector for MySqlDatamodelConnector {
         }
     }
 
-    fn validate_model(&self, model: walkers::ModelWalker<'_>, errors: &mut Diagnostics) {
+    fn validate_model(&self, model: walkers::ModelWalker<'_>, relation_mode: RelationMode, errors: &mut Diagnostics) {
         for index in model.indexes() {
             validations::field_types_can_be_used_in_an_index(self, index, errors);
         }
 
         if let Some(pk) = model.primary_key() {
             validations::field_types_can_be_used_in_a_primary_key(self, pk, errors);
         }
+
+        if relation_mode.uses_foreign_keys() {
+            for field in model.relation_fields() {
+                validations::uses_native_referential_action_set_default(self, field, errors);
+            }
+        }
     }
 
     fn constraint_violation_scopes(&self) -> &'static [ConstraintScope] {

psl/builtin-connectors/src/mysql_datamodel_connector/validations.rs

@@ -1,7 +1,10 @@
+use psl_core::diagnostics::{DatamodelWarning, Span};
+use psl_core::parser_database::ast::WithSpan;
+use psl_core::parser_database::ReferentialAction;
 use psl_core::{
     datamodel_connector::{walker_ext_traits::ScalarFieldWalkerExt, Connector},
     diagnostics::Diagnostics,
-    parser_database::walkers::{IndexWalker, PrimaryKeyWalker},
+    parser_database::walkers::{IndexWalker, PrimaryKeyWalker, RelationFieldWalker},
 };
 
 const LENGTH_GUIDE: &str = " Please use the `length` argument to the field in the index definition to allow this.";
@@ -89,3 +92,35 @@ pub(crate) fn field_types_can_be_used_in_a_primary_key(
         break;
     }
 }
+
+pub(crate) fn uses_native_referential_action_set_default(
+    connector: &dyn Connector,
+    field: RelationFieldWalker<'_>,
+    diagnostics: &mut Diagnostics,
+) {
+    let get_span = |referential_action_type: &str| -> Span {
+        field
+            .ast_field()
+            .span_for_argument("relation", referential_action_type)
+            .unwrap_or_else(|| field.ast_field().span())
+    };
+
+    let warning_msg = || {
+        format!(
+            "Using {set_default} on {connector} may yield to unexpected results, as the database will silently change the referential action to `{no_action}`.",
+            set_default = ReferentialAction::SetDefault.as_str(),
+            connector = connector.name(),
+            no_action = ReferentialAction::NoAction.as_str(),
+        )
+    };
+
+    if let Some(ReferentialAction::SetDefault) = field.explicit_on_delete() {
+        let span = get_span("onDelete");
+        diagnostics.push_warning(DatamodelWarning::new(warning_msg(), span));
+    }
+
+    if let Some(ReferentialAction::SetDefault) = field.explicit_on_update() {
+        let span = get_span("onUpdate");
+        diagnostics.push_warning(DatamodelWarning::new(warning_msg(), span));
+    }
+}

psl/builtin-connectors/src/postgres_datamodel_connector.rs

@@ -8,7 +8,8 @@ use enumflags2::BitFlags;
 use lsp_types::{CompletionItem, CompletionItemKind, CompletionList, InsertTextFormat};
 use psl_core::{
     datamodel_connector::{
-        Connector, ConnectorCapability, ConstraintScope, NativeTypeConstructor, NativeTypeInstance, StringFilter,
+        Connector, ConnectorCapability, ConstraintScope, NativeTypeConstructor, NativeTypeInstance, RelationMode,
+        StringFilter,
     },
     diagnostics::Diagnostics,
     parser_database::{ast, walkers, IndexAlgorithm, OperatorClass, ParserDatabase, ReferentialAction, ScalarType},
@@ -361,7 +362,7 @@ impl Connector for PostgresDatamodelConnector {
         }
     }
 
-    fn validate_model(&self, model: walkers::ModelWalker<'_>, errors: &mut Diagnostics) {
+    fn validate_model(&self, model: walkers::ModelWalker<'_>, _: RelationMode, errors: &mut Diagnostics) {
         for index in model.indexes() {
             validations::compatible_native_types(index, self, errors);
             validations::generalized_index_validations(index, self, errors);

psl/diagnostics/src/collection.rs

@@ -62,6 +62,17 @@ impl Diagnostics {
 
         String::from_utf8_lossy(&message).into_owned()
     }
+
+    pub fn warnings_to_pretty_string(&self, file_name: &str, datamodel_string: &str) -> String {
+        let mut message: Vec<u8> = Vec::new();
+
+        for warn in self.warnings() {
+            warn.pretty_print(&mut message, file_name, datamodel_string)
+                .expect("printing datamodel warning");
+        }
+
+        String::from_utf8_lossy(&message).into_owned()
+    }
 }
 
 impl From<DatamodelError> for Diagnostics {

psl/diagnostics/src/warning.rs

@@ -14,7 +14,9 @@ pub struct DatamodelWarning {
 }
 
 impl DatamodelWarning {
-    fn new(message: String, span: Span) -> DatamodelWarning {
+    /// You should avoid using this constructor directly when possible, and define warnings as public methods of this class.
+    /// The constructor is only left public for supporting connector-specific warnings (which should not live in the core).
+    pub fn new(message: String, span: Span) -> DatamodelWarning {
         DatamodelWarning { message, span }
     }
 

psl/psl-core/src/datamodel_connector.rs

@@ -148,7 +148,7 @@ pub trait Connector: Send + Sync {
     }
 
     fn validate_enum(&self, _enum: walkers::EnumWalker<'_>, _: &mut Diagnostics) {}
-    fn validate_model(&self, _model: walkers::ModelWalker<'_>, _: &mut Diagnostics) {}
+    fn validate_model(&self, _model: walkers::ModelWalker<'_>, _: RelationMode, _: &mut Diagnostics) {}
     fn validate_datasource(&self, _: BitFlags<PreviewFeature>, _: &Datasource, _: &mut Diagnostics) {}
 
     fn validate_scalar_field_unknown_default_functions(

psl/psl-core/src/validate/validation_pipeline/validations/models.rs

@@ -240,7 +240,7 @@ pub(crate) fn primary_key_connector_specific(model: ModelWalker<'_>, ctx: &mut C
 }
 
 pub(super) fn connector_specific(model: ModelWalker<'_>, ctx: &mut Context<'_>) {
-    ctx.connector.validate_model(model, ctx.diagnostics)
+    ctx.connector.validate_model(model, ctx.relation_mode, ctx.diagnostics)
 }
 
 pub(super) fn id_has_fields(model: ModelWalker<'_>, ctx: &mut Context<'_>) {

psl/psl/tests/validation/mysql/set_default_no_warning_when_relation_mode_prisma.prisma

@@ -0,0 +1,32 @@
+generator client {
+    provider = "prisma-client-js"
+}
+
+datasource db {
+    provider = "mysql"
+    url = "mysql://"
+    relationMode = "prisma"
+}
+
+model A {
+    id Int @id
+    bs B[]
+}
+
+model B {
+    id Int   @id
+    aId Int? @default(3)
+    a   A?   @relation(fields: [aId], references: [id], onUpdate: SetDefault, onDelete: SetDefault)
+}
+// error: Error validating: Invalid referential action: `SetDefault`. Allowed values: (`Cascade`, `Restrict`, `NoAction`, `SetNull`)
+//   -->  schema.prisma:19
+//    | 
+// 18 |     aId Int? @default(3)
+// 19 |     a   A?   @relation(fields: [aId], references: [id], onUpdate: SetDefault, onDelete: SetDefault)
+//    | 
+// error: Error validating: Invalid referential action: `SetDefault`. Allowed values: (`Cascade`, `Restrict`, `NoAction`, `SetNull`)
+//   -->  schema.prisma:19
+//    | 
+// 18 |     aId Int? @default(3)
+// 19 |     a   A?   @relation(fields: [aId], references: [id], onUpdate: SetDefault, onDelete: SetDefault)
+//    | 

psl/psl/tests/validation/mysql/set_default_warning.prisma

@@ -0,0 +1,27 @@
+datasource db {
+    provider = "mysql"
+    url = "mysql://"
+}
+
+model A {
+    id Int @id
+    bs B[]
+}
+
+model B {
+    id Int   @id
+    aId Int? @default(3)
+    a   A?   @relation(fields: [aId], references: [id], onUpdate: SetDefault, onDelete: SetDefault)
+}
+// warning: Using SetDefault on MySQL may yield to unexpected results, as the database will silently change the referential action to `NoAction`.
+//   -->  schema.prisma:14
+//    | 
+// 13 |     aId Int? @default(3)
+// 14 |     a   A?   @relation(fields: [aId], references: [id], onUpdate: SetDefault, onDelete: SetDefault)
+//    | 
+// warning: Using SetDefault on MySQL may yield to unexpected results, as the database will silently change the referential action to `NoAction`.
+//   -->  schema.prisma:14
+//    | 
+// 13 |     aId Int? @default(3)
+// 14 |     a   A?   @relation(fields: [aId], references: [id], onUpdate: SetDefault, onDelete: SetDefault)
+//    | 

psl/psl/tests/validation/mysql/set_default_warning_when_relation_mode_foreignkeys.prisma

@@ -0,0 +1,32 @@
+generator client {
+    provider = "prisma-client-js"
+}
+
+datasource db {
+    provider = "mysql"
+    url = "mysql://"
+    relationMode = "foreignKeys"
+}
+
+model A {
+    id Int @id
+    bs B[]
+}
+
+model B {
+    id Int   @id
+    aId Int? @default(3)
+    a   A?   @relation(fields: [aId], references: [id], onUpdate: SetDefault, onDelete: SetDefault)
+}
+// warning: Using SetDefault on MySQL may yield to unexpected results, as the database will silently change the referential action to `NoAction`.
+//   -->  schema.prisma:19
+//    | 
+// 18 |     aId Int? @default(3)
+// 19 |     a   A?   @relation(fields: [aId], references: [id], onUpdate: SetDefault, onDelete: SetDefault)
+//    | 
+// warning: Using SetDefault on MySQL may yield to unexpected results, as the database will silently change the referential action to `NoAction`.
+//   -->  schema.prisma:19
+//    | 
+// 18 |     aId Int? @default(3)
+// 19 |     a   A?   @relation(fields: [aId], references: [id], onUpdate: SetDefault, onDelete: SetDefault)
+//    |