Implement mapBinding mssql dialect option (#5292)

lib/dialects/mssql/index.js

@@ -333,14 +333,24 @@ class Client_MSSQL extends Client {
   _typeForBinding(binding) {
     const Driver = this._driver();
 
+    if (
+      this.connectionSettings.options &&
+      this.connectionSettings.options.mapBinding
+    ) {
+      const result = this.connectionSettings.options.mapBinding(binding);
+      if (result) {
+        return [result.value, result.type];
+      }
+    }
+
     switch (typeof binding) {
       case 'string':
-        return Driver.TYPES.NVarChar;
+        return [binding, Driver.TYPES.NVarChar];
       case 'boolean':
-        return Driver.TYPES.Bit;
+        return [binding, Driver.TYPES.Bit];
       case 'number': {
         if (binding % 1 !== 0) {
-          return Driver.TYPES.Float;
+          return [binding, Driver.TYPES.Float];
         }
 
         if (binding < SQL_INT4.MIN || binding > SQL_INT4.MAX) {
@@ -350,25 +360,21 @@ class Client_MSSQL extends Client {
             );
           }
 
-          return Driver.TYPES.BigInt;
+          return [binding, Driver.TYPES.BigInt];
         }
 
-        return Driver.TYPES.Int;
+        return [binding, Driver.TYPES.Int];
       }
       default: {
-        // if (binding === null || typeof binding === 'undefined') {
-        //   return tedious.TYPES.Null;
-        // }
-
         if (binding instanceof Date) {
-          return Driver.TYPES.DateTime;
+          return [binding, Driver.TYPES.DateTime];
         }
 
         if (binding instanceof Buffer) {
-          return Driver.TYPES.VarBinary;
+          return [binding, Driver.TYPES.VarBinary];
         }
 
-        return Driver.TYPES.NVarChar;
+        return [binding, Driver.TYPES.NVarChar];
       }
     }
   }
@@ -401,8 +407,8 @@ class Client_MSSQL extends Client {
   }
 
   // sets a request input parameter. Detects bigints and decimals and sets type appropriately.
-  _setReqInput(req, i, binding) {
-    const tediousType = this._typeForBinding(binding);
+  _setReqInput(req, i, inputBinding) {
+    const [binding, tediousType] = this._typeForBinding(inputBinding);
     const bindingName = 'p'.concat(i);
     let options;
 

test/integration2/dialects/mssql.spec.js

@@ -1,4 +1,5 @@
 const { expect } = require('chai');
+const { TYPES } = require('tedious');
 const { getAllDbs, getKnexForDb } = require('../util/knex-instance-provider');
 
 async function fetchDefaultConstraint(knex, table, column) {
@@ -31,6 +32,8 @@ describe('MSSQL dialect', () => {
         beforeEach(async () => {
           await knex.schema.createTable('test', function () {
             this.increments('id').primary();
+            this.specificType('varchar', 'varchar(100)');
+            this.string('nvarchar');
           });
         });
 
@@ -362,6 +365,31 @@ describe('MSSQL dialect', () => {
             return result ? result.comment : undefined;
           }
         });
+
+        describe('supports mapBinding config', async () => {
+          it('can remap types', async () => {
+            const query = knex('test')
+              .where('varchar', { value: 'testing', type: TYPES.VarChar })
+              .select('id');
+            const { bindings } = query.toSQL().toNative();
+            expect(bindings[0].type, TYPES.VarChar);
+            expect(bindings[0].value, 'testing');
+
+            // verify the query runs successfully
+            await query;
+          });
+          it('undefined mapBinding result falls back to default implementation', async () => {
+            const query = knex('test')
+              .where('nvarchar', 'testing')
+              .select('id');
+
+            const { bindings } = query.toSQL().toNative();
+            expect(bindings[0], 'testing');
+
+            // verify the query runs successfully
+            await query;
+          });
+        });
       });
     });
 });

test/integration2/util/knex-instance-provider.js

@@ -173,6 +173,13 @@ const testConfigs = {
       server: 'localhost',
       port: 21433,
       database: 'knex_test',
+      options: {
+        mapBinding(value) {
+          if (value && value.type) {
+            return { value: value.value, type: value.type };
+          }
+        },
+      },
     },
     pool: pool,
     migrations,

types/index.d.ts

@@ -2887,6 +2887,7 @@ export declare namespace Knex {
       multiSubnetFailover?: boolean;
       packetSize?: number;
       trustServerCertificate?: boolean;
+      mapBinding?: (value: any) => ({ value: any, type: any } | undefined);
     }>;
     pool?: Readonly<{
       min?: number;