Sequelize patch to enable unique indices (including partial indices) for ON CONFLICT DO UPDATE with postgres or sqlite

sequelize+5.21.12.patch

diff --git a/node_modules/sequelize/lib/dialects/abstract/query-generator.js b/node_modules/sequelize/lib/dialects/abstract/query-generator.js
index d2c865d..b668f38 100755
--- a/node_modules/sequelize/lib/dialects/abstract/query-generator.js
+++ b/node_modules/sequelize/lib/dialects/abstract/query-generator.js
@@ -302,9 +302,16 @@ class QueryGenerator {
     if (this._dialect.supports.inserts.updateOnDuplicate && options.updateOnDuplicate) {
       if (this._dialect.supports.inserts.updateOnDuplicate == ' ON CONFLICT DO UPDATE SET') { // postgres / sqlite
         // If no conflict target columns were specified, use the primary key names from options.upsertKeys
-        const conflictKeys = options.upsertKeys.map(attr => this.quoteIdentifier(attr));
         const updateKeys = options.updateOnDuplicate.map(attr => `${this.quoteIdentifier(attr)}=EXCLUDED.${this.quoteIdentifier(attr)}`);
-        onDuplicateKeyUpdate = ` ON CONFLICT (${conflictKeys.join(',')}) DO UPDATE SET ${updateKeys.join(',')}`;
+        if (Array.isArray(options.upsertKeys)) {
+          const conflictKeys = options.upsertKeys.map(attr => this.quoteIdentifier(attr));
+          onDuplicateKeyUpdate = ` ON CONFLICT (${conflictKeys.join(',')}) DO UPDATE SET ${updateKeys.join(',')}`;
+        } else {
+          // If upsertKeys is an object, generate an ON CONFLICT WHERE
+          const conflictKeys = options.upsertKeys.fields.map(attr => this.quoteIdentifier(attr));
+          const where = this.whereQuery(options.upsertKeys.where);
+          onDuplicateKeyUpdate = ` ON CONFLICT (${conflictKeys.join(',')}) ${where} DO UPDATE SET ${updateKeys.join(',')}`;
+        }
       } else { // mysql / maria
         const valueKeys = options.updateOnDuplicate.map(attr => `${this.quoteIdentifier(attr)}=VALUES(${this.quoteIdentifier(attr)})`);
         onDuplicateKeyUpdate = `${this._dialect.supports.inserts.updateOnDuplicate} ${valueKeys.join(',')}`;
diff --git a/node_modules/sequelize/lib/model.js b/node_modules/sequelize/lib/model.js
index a4d957b..c9aa9ee 100644
--- a/node_modules/sequelize/lib/model.js
+++ b/node_modules/sequelize/lib/model.js
@@ -2704,10 +2704,22 @@ class Model {
           // Map updateOnDuplicate attributes to fields
           if (options.updateOnDuplicate) {
             options.updateOnDuplicate = options.updateOnDuplicate.map(attr => model.rawAttributes[attr].field || attr);
-            // Get primary keys for postgres to enable updateOnDuplicate
-            options.upsertKeys = _.chain(model.primaryKeys).values().map('field').value();
-            if (Object.keys(model.uniqueKeys).length > 0) {
-              options.upsertKeys = _.chain(model.uniqueKeys).values().filter(c => c.fields.length === 1).map(c => c.fields[0]).value();
+            if (options.upsertIndex !== undefined) {
+              const upsertIndex = model._indexes.find(index => index.name === options.upsertIndex);
+              if (upsertIndex === undefined) {
+                throw new Error(`upsertIndex '${options.upsertIndex}' not defined.`);
+              }
+              if (!upsertIndex.unique) {
+                throw new Error(`upsertIndex '${options.upsertIndex}' not a unique index.`);
+              }
+              options.upsertKeys = { fields: upsertIndex.fields, where: upsertIndex.where };
+            }
+            if (options.upsertKeys == null) {
+              // Get primary keys for postgres to enable updateOnDuplicate
+              options.upsertKeys = _.chain(model.primaryKeys).values().map('field').value();
+              if (Object.keys(model.uniqueKeys).length > 0) {
+                options.upsertKeys = _.chain(model.uniqueKeys).values().filter(c => c.fields.length === 1).map(c => c.fields[0]).value();
+              }
             }
           }
 
diff --git a/node_modules/sequelize/types/lib/model.d.ts b/node_modules/sequelize/types/lib/model.d.ts
index 0f5ad3a..7d4b040 100644
--- a/node_modules/sequelize/types/lib/model.d.ts
+++ b/node_modules/sequelize/types/lib/model.d.ts
@@ -754,6 +754,20 @@ export interface BulkCreateOptions extends Logging, Transactionable {
    */
   updateOnDuplicate?: string[];
 
+  /**
+   * The name of a unique index to be used for generation of an `ON CONFLICT`
+   * clause. (Only supported by SQLite >= 3.24.0 & Postgres >= 9.5)
+   */
+  upsertIndex?: string;
+
+  /**
+   * Either an array of database columns that are either primary keys or
+   * composite members of a unique key, or an object containing fields and a
+   * where clause that represents a partial index. Used for generating an `ON
+   * CONFLICT` clause. (Only supported by SQLite >= 3.24.0 & Postgres >= 9.5)
+   */
+  upsertKeys?: string[] | { fields: string[], where: WhereOptions };
+
   /**
    * Include options. See `find` for details
    */