taskrun: include actual result size in error when exceeding maxResultSize

[a-ateek]

Fixes #8868

Changes

Previously, when a TaskRun failed due to a result exceeding the maxResultSize, the error message did not include the actual size of the offending result. This makes it harder for users to figure out how much they exceeded the configured limit.

Example:

  Conditions:
    Last Transition Time:  2025-07-03T17:59:57Z
    Message:               [User error]  TaskRun ""max-size-run"" failed: results exceeded size limit 20 bytes
    Reason:                TaskRunResultLargerThanAllowedLimit

This change improves the error message to include the actual size to debug pipelines with large results.
Example:

  Conditions:
    Last Transition Time:  2025-07-05T12:08:56Z
    Message:               [User error]  TaskRun ""max-size-run"" failed: 47 bytes results size exceeds configured limit of 20 bytes
    Reason:                TaskRunResultLargerThanAllowedLimit

Submitter Checklist

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• Has Tests included if any functionality added or changed
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Release Notes

Improved error message when a TaskRun result exceeds `maxResultSize` to include the actual result size, making it easier to debug oversized results

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: a-ateek / name: Ateek (f80e6f0)

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[tekton-robot]

The following is the coverage report on the affected files.
Say /test pull-tekton-pipeline-go-coverage-df to re-run this coverage report

File	Old Coverage	New Coverage	Delta
internal/sidecarlogresults/sidecarlogresults.go	87.7%	86.0%	-1.7
pkg/reconciler/taskrun/taskrun.go	85.9%	85.9%	-0.0

[a-ateek]

/kind feature

[tekton-robot]

The following is the coverage report on the affected files.
Say /test pull-tekton-pipeline-go-coverage-df to re-run this coverage report

File	Old Coverage	New Coverage	Delta
internal/sidecarlogresults/sidecarlogresults.go	87.7%	86.0%	-1.7
pkg/reconciler/taskrun/taskrun.go	85.9%	85.9%	-0.0

[pritidesai]

Thank you @a-ateek for this PR. Please consider adding unit tests to cover the proposed changes.

[tekton-robot]

The following is the coverage report on the affected files.
Say /test pull-tekton-pipeline-go-coverage-df to re-run this coverage report

File	Old Coverage	New Coverage	Delta
internal/sidecarlogresults/sidecarlogresults.go	87.7%	86.0%	-1.7
pkg/reconciler/taskrun/taskrun.go	85.9%	85.9%	-0.0

[tekton-robot]

The following is the coverage report on the affected files.
Say /test pull-tekton-pipeline-go-coverage-df to re-run this coverage report

File	Old Coverage	New Coverage	Delta
internal/sidecarlogresults/sidecarlogresults.go	87.7%	86.0%	-1.7
pkg/reconciler/taskrun/taskrun.go	85.9%	85.9%	-0.0

[tekton-robot]

The following is the coverage report on the affected files.
Say /test pull-tekton-pipeline-go-coverage-df to re-run this coverage report

File	Old Coverage	New Coverage	Delta
internal/sidecarlogresults/sidecarlogresults.go	87.7%	86.0%	-1.7
pkg/reconciler/taskrun/taskrun.go	85.9%	85.9%	-0.0

[tekton-robot]

The following is the coverage report on the affected files.
Say /test pull-tekton-pipeline-go-coverage-df to re-run this coverage report

File	Old Coverage	New Coverage	Delta
internal/sidecarlogresults/sidecarlogresults.go	87.7%	86.0%	-1.7
pkg/reconciler/taskrun/taskrun.go	85.9%	85.9%	-0.0

[a-ateek]

@pritidesai Unit tests already existed for this function and now I have adjusted them according to new error message. Thank you for pointing that out. Also rebased the branch.

[waveywaves]

/retest

[waveywaves]

/retest

[waveywaves]

@a-ateek would you mind squashing your commits, rebasing and pushing your branch again ? we have recently removed some gittea tests which might be causing these test failures. Just to eliminate the possiblility a rebase would be great.

[tekton-robot]

The following is the coverage report on the affected files.
Say /test pull-tekton-pipeline-go-coverage-df to re-run this coverage report

File	Old Coverage	New Coverage	Delta
internal/sidecarlogresults/sidecarlogresults.go	87.6%	86.1%	-1.5
pkg/pod/status.go	92.2%	92.4%	0.2
pkg/reconciler/taskrun/taskrun.go	86.5%	86.5%	-0.0

[a-ateek]

/retest

[tekton-robot]

@a-ateek: Cannot trigger testing until a trusted user reviews the PR and leaves an /ok-to-test message.

In response to this:

/retest

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[waveywaves]

/ok-to-test