Issue 7016 - Convert serialization functions into generators

lib/subscriptionClasses.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-present eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 107 matching lines @@
     if (value != this._disabled)
     {
       let oldValue = this._disabled;
       this._disabled = value;
       filterNotifier.emit("subscription.disabled", this, value, oldValue);
     }
     return this._disabled;
   },
 
   /**
-   * Serializes the subscription to an array of strings for writing
-   * out on the disk.
+   * Serializes the subscription for writing out on disk.
    * @yields {string}
    */
   *serialize()
   {
+    let {url, type, _title, _fixedTitle, _disabled} = this;
+
     yield "[Subscription]";
-    yield "url=" + this.url;
-
-    if (this.type)
-      yield "type=" + this.type;
-    if (this._title)
-      yield "title=" + this._title;
-    if (this._fixedTitle)
+    yield "url=" + url;
+
+    if (type)
+      yield "type=" + type;
+    if (_title)
+      yield "title=" + _title;
+    if (_fixedTitle)
       yield "fixedTitle=true";
-    if (this._disabled)
+    if (_disabled)
       yield "disabled=true";
   },
 
   *serializeFilters()
   {
-    for (let filter of this.filters)
+    let {filters} = this;
+
+    yield "[Subscription filters]";
+
+    for (let filter of filters)
       yield filter.text.replace(/\[/g, "\\[");
   },
 
   toString()
   {
     return [...this.serialize()].join("\n");
   }
 };
 
 /**
@@ skipping 115 matching lines @@
 
     return false;
   },
 
   /**
    * See Subscription.serialize()
    * @inheritdoc
    */
   *serialize()
   {
+    let {defaults, _lastDownload} = this;
+
     yield* Subscription.prototype.serialize.call(this);
-    if (this.defaults && this.defaults.length)
+
+    if (defaults)
     {
       yield "defaults=" +
-        this.defaults.filter(
-          type => SpecialSubscription.defaultsMap.has(type)
-        ).join(" ")
-      ;
-    }
-    if (this._lastDownload)
-      yield "lastDownload=" + this._lastDownload;
+            defaults.filter(
+              type => SpecialSubscription.defaultsMap.has(type)
+            ).join(" ");
+    }
+    if (_lastDownload)
+      yield "lastDownload=" + _lastDownload;
   }
 });
 
 SpecialSubscription.defaultsMap = new Map([
   ["whitelist", WhitelistFilter],
   ["blocking", BlockingFilter],
   ["elemhide", ElemHideBase]
 ]);
 
 /**
@@ skipping 87 matching lines @@
     }
     return this._lastDownload;
   },
 
   /**
    * See Subscription.serialize()
    * @inheritdoc
    */
   *serialize()
   {
+    let {_homepage, _lastDownload} = this;
+
     yield* Subscription.prototype.serialize.call(this);
-    if (this._homepage)
-      yield "homepage=" + this._homepage;
-    if (this._lastDownload)
-      yield "lastDownload=" + this._lastDownload;
+
+    if (_homepage)
+      yield "homepage=" + _homepage;
+    if (_lastDownload)
+      yield "lastDownload=" + _lastDownload;
   }
 });
 
 /**
  * Class for filter subscriptions updated externally (by other extension)
  * @param {string} url    see {@link Subscription Subscription()}
  * @param {string} [title]  see {@link Subscription Subscription()}
  * @constructor
  * @augments RegularSubscription
  */
 function ExternalSubscription(url, title)
 {
   RegularSubscription.call(this, url, title);
 }
 exports.ExternalSubscription = ExternalSubscription;
 
 ExternalSubscription.prototype = extend(RegularSubscription, {
   /**
    * See Subscription.serialize()
    * @inheritdoc
    */
-  *serialize()
-  {
-    yield new Error(
+  *serialize() // eslint-disable-line require-yield
+  {
+    throw new Error(
       "Unexpected call, external subscriptions should not be serialized"
     );
   }
 });
 
 /**
  * Class for filter subscriptions updated externally (by other extension)
  * @param {string} url  see {@link Subscription Subscription()}
  * @param {string} [title]  see {@link Subscription Subscription()}
  * @constructor
@@ skipping 104 matching lines @@
    * @type {number}
    */
   downloadCount: 0,
 
   /**
    * See Subscription.serialize()
    * @inheritdoc
    */
   *serialize()
   {
+    let {downloadStatus, lastSuccess, lastCheck, expires,
+         softExpiration, errors, version, requiredVersion,
+         downloadCount} = this;
+
     yield* RegularSubscription.prototype.serialize.call(this);
-    if (this.downloadStatus)
-      yield "downloadStatus=" + this.downloadStatus;
-    if (this.lastSuccess)
-      yield "lastSuccess=" + this.lastSuccess;
-    if (this.lastCheck)
-      yield "lastCheck=" + this.lastCheck;
-    if (this.expires)
-      yield "expires=" + this.expires;
-    if (this.softExpiration)
-      yield "softExpiration=" + this.softExpiration;
-    if (this.errors)
-      yield "errors=" + this.errors;
-    if (this.version)
-      yield "version=" + this.version;
-    if (this.requiredVersion)
-      yield "requiredVersion=" + this.requiredVersion;
-    if (this.downloadCount)
-      yield "downloadCount=" + this.downloadCount;
+
+    if (downloadStatus)
+      yield "downloadStatus=" + downloadStatus;
+    if (lastSuccess)
+      yield "lastSuccess=" + lastSuccess;
+    if (lastCheck)
+      yield "lastCheck=" + lastCheck;
+    if (expires)
+      yield "expires=" + expires;
+    if (softExpiration)
+      yield "softExpiration=" + softExpiration;
+    if (errors)
+      yield "errors=" + errors;
+    if (version)
+      yield "version=" + version;
+    if (requiredVersion)
+      yield "requiredVersion=" + requiredVersion;
+    if (downloadCount)
+      yield "downloadCount=" + downloadCount;
   }
 });