Job strangeness when progress: and title: are both updated

[fuhrmanator]

I'm using Job to show progress bars on my code and I sometimes find that the message is "off by one" from the progress. I created a MWE below that reproduces the bug in Pharo 7 on Windows and Unix (WSL):

| myColl |
myColl := 1 to: 3.
[ :job | 
myColl do: [ :e | 
    job
        progress: e/(myColl size); 
    title: 'waiting ' , e asString.
    (Delay forSeconds: 3) wait ] ] asJob run

What I see is

• Progress bar appears with 1/3 of a bar and no message.
• 3 seconds pass
• Progress bar appears with 1/3 of a bar and message 'Waiting 1/3'
• 3 seconds pass
• Progress bar appears with 2/3 of a bar and message 'Waiting 2/3'
• 3 seconds pass
• Progress bar disappears

So, from this I see a bug that the first message never appears and the last message and progress (3/3) never appears.

However:

• If I take out the title: call (only leaving the progress: update), it works as expected.
• If I take out the progress: call (only leaving the title: update), it works as expected.

The reason I'm interested in using both title: and progress: is that I have jobs with several long steps (cloning a git, creating metamodels, etc.) and I want to show progress along with a feedback for which step is running. This seems like a bug, but maybe I'm not using Job appropriately?

[stale[bot]]

To limit bug bankruptcy (see https://www.joelonsoftware.com/2012/07/09/software-inventory/) this issue has been automatically marked as stale because it has not had any activity in 6 months. It will be closed in 1 month if no further activity occurs. If this issue remains important to you, please comment to reactivate the issue. Thank you for your contributions.

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[jecisc]

Keep

[kamk]

It has likely something to do with refresh rate defined in SystemProgressMorph>>update: When a small delay is added between sending progress: and title:, it looks like it works:

myColl do: [ :e | 
    job progress: e / (myColl size).
    (Delay forMilliseconds: 60) wait.
    job title: 'Waiting ', e asString.
    (Delay forSeconds: 2) wait ] ] asJob run

[astares]

Still valid in Pharo 12/Pharo 13