add general message for integer64 columns (issue #3611)

[AmanKashyap0807]

closes #3611

Overview

PR addresses issue #3611 by adding a notification when fread() automatically creates interger64 columns.

Changes

• fread.R : added a check to identify if any columns were read as integer64, if detected a message is emitted.
• tests.Rraw : added new tests (1017.5 and 1017.6) to verify the message emitted.
  updated existing tests that use integer64 data to suppress this new message where it is not the focus of the test
• NEWS.md : added an entry under big fixes.

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Reproduction

issue #3611

env : windows 11, R 4.5.2, data.table 1.18.2.1 (installed from CRAN)

fread() automatically creats interger64 columns when reading large instegers but does not emit any warning or message.

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I also reproduced the same behavior using the current github codebase (by compiliing data.table from source) , the behavious is identical

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[AmanKashyap0807]

Hi mentors,

This is my test contribution for the data.table gsoc project.
I would appreciate your feedback

If there is any issue you would prefer me to work on next, I would be happy to take it up.
In the meantime, I’m exploring another issue to continue learning the codebase.

@tdhock @Anirban166 @DorisAmoakohene @joshhwuu

[joshhwuu]

it seems that we might be holding off on a fix for this on data.table's side, at least for now: #3611 (comment)

[AmanKashyap0807]

Thanks for the clarification @joshhwuu

Thanks for taking a look, and please let me know if there’s another issue or area where a contribution would be more helpful at the moment.

I’ll keep this branch as it is in case it’s useful to revisit later.