Include _debug property in QueryBuilder#clone.

Adds a test for `QueryBuilder#clone`. Changes `clone()` behaviour to transfer the debug flag (`QueryBuilder#_debug`) to the cloned instance.

Fixes #1080

lib/query/builder.js

@@ -11,6 +11,8 @@ var EventEmitter = require('events').EventEmitter;
 var Raw = require('../raw');
 var helpers = require('../helpers');
 var JoinClause = require('./joinclause');
+var _clone = require('lodash/lang/clone');
+var isUndefined = require('lodash/lang/isUndefined');
 var assign = require('lodash/object/assign');
 
 // Typically called from `knex.builder`,
@@ -20,13 +22,13 @@ function Builder(client) {
   this.and = this;
   this._single = {};
   this._statements = [];
+  this._method = 'select';
+  this._debug = client.config && client.config.debug;
 
   // Internal flags used in the builder.
-  this._method = 'select';
   this._joinFlag = 'inner';
   this._boolFlag = 'and';
   this._notFlag = false;
-  this._debug = client.config && client.config.debug;
 }
 inherits(Builder, EventEmitter);
 
@@ -42,13 +44,17 @@ assign(Builder.prototype, {
   },
 
   // Create a shallow clone of the current query builder.
-  // TODO: Test this!!
   clone: function clone() {
     var cloned = new this.constructor(this.client);
     cloned._method = this._method;
-    cloned._single = _.clone(this._single);
-    cloned._options = _.clone(this._options);
-    cloned._statements = this._statements.slice();
+    cloned._single = _clone(this._single);
+    cloned._statements = _clone(this._statements);
+    cloned._debug = this._debug;
+
+    // `_option` is assigned by the `Interface` mixin.
+    if (!isUndefined(this._options)) {
+      cloned._options = _clone(this._options);
+    }
     return cloned;
   },
 

src/query/builder.js

@@ -9,6 +9,8 @@ var EventEmitter = require('events').EventEmitter
 var Raw          = require('../raw')
 var helpers      = require('../helpers')
 var JoinClause   = require('./joinclause')
+var clone        = require('lodash/lang/clone');
+var isUndefined  = require('lodash/lang/isUndefined');
 var assign       = require('lodash/object/assign');
 
 // Typically called from `knex.builder`,
@@ -18,13 +20,13 @@ function Builder(client) {
   this.and         = this;
   this._single     = {};
   this._statements = [];
+  this._method    = 'select'
+  this._debug     = client.config && client.config.debug;
 
   // Internal flags used in the builder.
-  this._method    = 'select'
   this._joinFlag  = 'inner';
   this._boolFlag  = 'and';
   this._notFlag   = false;
-  this._debug     = client.config && client.config.debug;
 }
 inherits(Builder, EventEmitter);
 
@@ -40,13 +42,18 @@ assign(Builder.prototype, {
   },
 
   // Create a shallow clone of the current query builder.
-  // TODO: Test this!!
-  clone: function() {
-    var cloned            = new this.constructor(this.client);
-      cloned._method      = this._method;
-      cloned._single      = _.clone(this._single);
-      cloned._options     = _.clone(this._options);
-      cloned._statements  = this._statements.slice();
+  clone() {
+    const cloned        = new this.constructor(this.client);
+    cloned._method      = this._method;
+    cloned._single      = clone(this._single);
+    cloned._statements  = clone(this._statements);
+    cloned._debug       = this._debug;
+
+    // `_option` is assigned by the `Interface` mixin.
+    if (!isUndefined(this._options)) {
+      cloned._options = clone(this._options);
+    }
+
     return cloned;
   },
 

test/tape/query-builder.js

@@ -1,6 +1,7 @@
 'use strict';
 
 var tape         = require('tape')
+var omit         = require('lodash/object/omit')
 var QueryBuilder = require('../../lib/query/builder')
 var Client       = require('../../lib/client')
 
@@ -18,6 +19,35 @@ tape('allows for object syntax in join', function(t) {
     'accounts.id': 'users.account_id',
     'accounts.owner_id': 'users.id'
   }).toSQL('join')
-  t.equal(sql.sql, 
+  t.equal(sql.sql,
     'inner join "accounts" on "accounts"."id" = "users"."account_id" and "accounts"."owner_id" = "users"."id"')
 })
+
+tape('clones correctly', function(t) {
+  var qb = new QueryBuilder(new Client())
+  var original = qb.table('users').debug().innerJoin('accounts', {
+    'accounts.id': 'users.account_id',
+    'accounts.owner_id': 'users.id'
+  });
+
+  var cloned = original.clone();
+
+  t.notEqual(original, cloned);
+
+  // `deepEqual` freezes when it encounters circular references,
+  // so they must be omitted.
+  t.deepEqual(
+    omit(cloned, 'client', 'and'),
+    omit(original, 'client', 'and')
+  );
+
+  t.equal(
+    cloned.client,
+    original.client,
+    'clone references same client'
+  );
+
+  t.equal(cloned.and, cloned, 'cloned `and` references self');
+
+  t.end();
+});