845055 - "mimeType is null" in Page Info's makePreview()

Status: VERIFIED FIXED

(Firefox :: Page Info Window, defect)

Description

[Jesse Ruderman]

Attachment: testcase

1. Load the testcase.
2. Open the Page Info window (press Cmd+I)

JavaScript error: chrome://browser/content/pageinfo/pageInfo.js, line 987: mimeType is null

I'm guessing this is a regression from bug 792968 (similar to bug 797430).

https://hg.mozilla.org/mozilla-central/rev/9e32aa6fe544#l5.50 changed:

> -        (item instanceof HTMLObjectElement && /^image\//.test(mimeType)) || isBG) && isProtocolAllowed) {
> +         (item instanceof HTMLObjectElement && mimeType.startsWith("image/")) || isBG) && isProtocolAllowed) {

Comment 1

[Tanner M. Young [:tmyoung]]

Confirmed on Windows, too.

Comment 2

[:Gavin Sharp [email: [e-mail]]]

Yosy, can you fix this regression from your patch?

Comment 3

[Yosy]

(In reply to :Gavin Sharp (use [e-mail] for email) from comment #2)
> Yosy, can you fix this regression from your patch?

Hi, I don't have the firefox source code, I will download and compile it and will post a patch

Comment 4

[Yosy]

Attachment: Patch

Comment 5

[Philip Chee]

> -         (item instanceof HTMLObjectElement && mimeType.startsWith("image/")) || isBG) && isProtocolAllowed) {
. +         (item instanceof HTMLObjectElement && mimeType !== null && mimeType.startsWith("image/")) || isBG) && isProtocolAllowed) {

Does it work if you just use "&& mimeType" instead of "&& mimeType !== null" ?

Comment 6

[Yosy]

(In reply to Philip Chee from comment #5)
> > -         (item instanceof HTMLObjectElement && mimeType.startsWith("image/")) || isBG) && isProtocolAllowed) {
> . +         (item instanceof HTMLObjectElement && mimeType !== null &&
> mimeType.startsWith("image/")) || isBG) && isProtocolAllowed) {
> 
> Does it work if you just use "&& mimeType" instead of "&& mimeType !== null"
> ?
What is the difference?

Comment 7

[Philip Chee]

>> Does it work if you just use "&& mimeType" instead of "&& mimeType !== null" ?
> What is the difference?
It's shorter and easier to read and makes use of Javascript truthy/falsy behaviour:
<http://james.padolsey.com/javascript/truthy-falsey/>

Comment 8

[Dão Gottwald [:dao]]

Comment on attachment 720096 [details] [diff] [review]
Patch

Yes, please remove "!== null". r=me with that change. Thanks!

Comment 9

[Jesse Ruderman]

https://hg.mozilla.org/integration/mozilla-inbound/rev/b16eb3dac7bc

Comment 10

[Ed Morley [:emorley]]

https://hg.mozilla.org/mozilla-central/rev/b16eb3dac7bc

Comment 11

[Maria Grazia Alastra [:mga]]

Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:23.0) Gecko/20130428 Firefox/23.0
Mozilla/5.0 (X11; Linux x86_64; rv:23.0) Gecko/20130428 Firefox/23.0

Verified as fixed on Windows 7 x64 and Ubuntu 12.04 x86_64 with latest Nightly 23.0a1 (Build ID: 20130429030926)