Issue 4795 - Avoid shorthand method syntax where prototype matters

lib/compat.js

Index: lib/compat.js
diff --git a/lib/compat.js b/lib/compat.js
index 21439f3d353d904341f2b54ac7fe7f14190ac3bd..dcb231da0f5c9c881212dbad1efeba5290273e6c 100644
--- a/lib/compat.js
+++ b/lib/compat.js
@@ -55,8 +55,13 @@ let Components =
   interfaces:
   {
     nsIFile: {DIRECTORY_TYPE: 0},
-    nsIFileURL() {},
-    nsIHttpChannel() {},
+
+    // We don't use the method definition shorthand syntax for these functions

[Sebastian Noack, 2017/01/23 13:54:22]

I had a hard time to understand what is going on here. The problem is that this
is not really a class, but more like a namespace, while nsIFileURL and
nsIHttpChannel are meant to be classes themselves, and in order to define a
class's constructor you have to use the function statement (not the method
shorthand syntax). I wonder whether this comment could better clarify the issue.

[kzar, 2017/01/23 13:59:13]

It surely could, I'm open to suggestions.

[Sebastian Noack, 2017/02/16 12:05:10]

With our just established ESLint configuration this will also cause an error.
How about this:

  function nsIFileURL() {}
  function nsIHttpChannel() {}

  ...

  var Components =
  {
    interfaces:
    {
      ...

      nsIFileURL,
      nsIHttpChannel,

That would also make this comment redundant, IMO.

[kzar, 2017/02/17 09:40:28]

Done.

+    // since that gives them the prototype of undefined which breaks instanceof
+    // checks.
+    nsIFileURL: function() {},
+    nsIHttpChannel: function() {},
+
     nsITimer: {TYPE_REPEATING_SLACK: 0},
     nsIInterfaceRequestor: null,
     nsIChannelEventSink: null