Cleanup

node_modules/mongoose/lib/helpers/model/discriminator.js

@@ -1,5 +1,6 @@
 'use strict';
 
+const Mixed = require('../../schema/mixed');
 const defineKey = require('../document/compile').defineKey;
 const get = require('../get');
 const utils = require('../../utils');
@@ -62,7 +63,7 @@ module.exports = function discriminator(model, name, schema, tiedValue, applyPlu
   }
 
   let value = name;
-  if (typeof tiedValue == 'string' && tiedValue.length) {
+  if ((typeof tiedValue === 'string' && tiedValue.length) || tiedValue != null) {
     value = tiedValue;
   }
 
@@ -84,22 +85,25 @@ module.exports = function discriminator(model, name, schema, tiedValue, applyPlu
     for (const path of baseSchemaPaths) {
       if (schema.nested[path]) {
         conflictingPaths.push(path);
+        continue;
       }
 
       if (path.indexOf('.') === -1) {
         continue;
       }
-      const sp = path.split('.');
+      const sp = path.split('.').slice(0, -1);
       let cur = '';
       for (const piece of sp) {
         cur += (cur.length ? '.' : '') + piece;
-        if (schema.paths[cur] || schema.singleNestedPaths[cur]) {
+        if (schema.paths[cur] instanceof Mixed ||
+            schema.singleNestedPaths[cur] instanceof Mixed) {
           conflictingPaths.push(path);
         }
       }
     }
 
     utils.merge(schema, baseSchema, {
+      isDiscriminatorSchemaMerge: true,
       omit: { discriminators: true, base: true },
       omitNested: conflictingPaths.reduce((cur, path) => {
         cur['tree.' + path] = true;
@@ -122,17 +126,17 @@ module.exports = function discriminator(model, name, schema, tiedValue, applyPlu
       default: value,
       select: true,
       set: function(newName) {
-        if (newName === value) {
+        if (newName === value || (Array.isArray(value) && utils.deepEqual(newName, value))) {
           return value;
         }
         throw new Error('Can\'t set discriminator key "' + key + '"');
       },
       $skipDiscriminatorCheck: true
     };
-    obj[key][schema.options.typeKey] = existingPath ?
-      existingPath.instance :
-      String;
+    obj[key][schema.options.typeKey] = existingPath ? existingPath.options[schema.options.typeKey] : String;
     schema.add(obj);
+
+
     schema.discriminatorMapping = { key: key, value: value, isRoot: false };
 
     if (baseSchema.options.collection) {
@@ -149,11 +153,17 @@ module.exports = function discriminator(model, name, schema, tiedValue, applyPlu
 
     for (const _key of keys) {
       if (!CUSTOMIZABLE_DISCRIMINATOR_OPTIONS[_key]) {
+        // Special case: compiling a model sets `pluralization = true` by default. Avoid throwing an error
+        // for that case. See gh-9238
+        if (_key === 'pluralization' && schema.options[_key] == true && baseSchema.options[_key] == null) {
+          continue;
+        }
+
         if (!utils.deepEqual(schema.options[_key], baseSchema.options[_key])) {
           throw new Error('Can\'t customize discriminator option ' + _key +
-          ' (can only modify ' +
-          Object.keys(CUSTOMIZABLE_DISCRIMINATOR_OPTIONS).join(', ') +
-          ')');
+            ' (can only modify ' +
+            Object.keys(CUSTOMIZABLE_DISCRIMINATOR_OPTIONS).join(', ') +
+            ')');
         }
       }
     }