1682242 - UnknownException: TypeError: can't access property "tabs", tabBrowser is null

Status: RESOLVED FIXED

(Remote Protocol :: Marionette, defect, P1)

Description

[Henrik Skupin [:whimboo][⌚️UTC+1]]

With the patch on bug 1676671 landed, the initial browser collection is broken if there is a non-browser window open. The failure looks like:

1607940033466	Marionette	DEBUG	3 <- [1,1,{"error":"unknown error","message":"TypeError: can't access property \"tabs\", tabBrowser is null","stacktrace":"GeckoDr ... t@chrome://marionette/content/server.js:241:9\n_onJSONObjectReady/<@chrome://marionette/content/transport.js:504:20\n"},null]
Marionette threw an error: TypeError: can't access property "tabs", tabBrowser is null
GeckoDriver.prototype.newSession@chrome://marionette/content/driver.js:876:25
despatch@chrome://marionette/content/server.js:297:40
execute@chrome://marionette/content/server.js:267:16
onPacket/<@chrome://marionette/content/server.js:240:20
onPacket@chrome://marionette/content/server.js:241:9
_onJSONObjectReady/<@chrome://marionette/content/transport.js:504:20

Comment 1

[Henrik Skupin [:whimboo][⌚️UTC+1]]

I set this bug as high priority because this failure blocks Marionette unit tests for Thunderbird.

Comment 2

[Henrik Skupin [:whimboo][⌚️UTC+1]]

Attachment: Bug 1682242 - [marionette] Correctly register chrome windows without a tab browser in "WebDriver:NewSession".

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/bf468d20cd8e
[marionette] Correctly register chrome windows without a tab browser in "WebDriver:NewSession". r=marionette-reviewers,jgraham

Comment 4

[Cosmin Sabou [:CosminS]]

https://hg.mozilla.org/mozilla-central/rev/bf468d20cd8e

Comment 5

[Henrik Skupin [:whimboo][⌚️UTC+1]]

Comment on attachment 9193030 [details]
Bug 1682242 - [marionette] Correctly register chrome windows without a tab browser in "WebDriver:NewSession".

Beta/Release Uplift Approval Request

• User impact if declined: Using WebDriver (Marionette) the new session command will fail if windows are open that are no browser windows. This actually affects Thunderbird as well.
• Is this code covered by automated tests?: Yes
• Has the fix been verified in Nightly?: Yes
• Needs manual test from QE?: No
• If yes, steps to reproduce:
• List of other uplifts needed: None
• Risk to taking this patch: Low
• Why is the change risky/not risky? (and alternatives if risky): A null check has been added to prevent the Javascript error.
• String changes made/needed: none

Comment 6

[Julien Cristau [:jcristau] (back April 22)]

Comment on attachment 9193030 [details]
Bug 1682242 - [marionette] Correctly register chrome windows without a tab browser in "WebDriver:NewSession".

approved for 85.0b2

Comment 7

[Julien Cristau [:jcristau] (back April 22)]

https://hg.mozilla.org/releases/mozilla-beta/rev/a1d51a0f3b9d

Comment 8

[Intermittent Failures Robot]

2 failures in 3421 pushes (0.001 failures/push) were associated with this bug in the last 7 days.

Repository breakdown:

• comm-central: 2

Platform breakdown:

• linux64-shippable: 2

For more details, see:
https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=1682242&startday=2020-12-14&endday=2020-12-20&tree=all