executor,expression: avoid to append nil to warnings

[zyguan]

Signed-off-by: zyguan zhongyangguan@gmail.com

What problem does this PR solve?

Issue Number: close #31569

Problem Summary: two issues are described in #31569:

1. nil pointer exception was thrown when show warnings.
2. the warning messages were incompleted (missing template args).

What is changed and how it works?

Previously we always append the warning error even when it's a nil here, which leads to the first issue. This PR uses sc.HandleTruncate to handle trancate warnings uniformly and amends warnings generated on inserting.

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

None

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• tangenta
• xhebox

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[hawkingrei]

/run-all-tests

[tangenta]

@zyguan Please fix the following failed integration tests:

TestInsertWrongValueForField – executor
TestInsert – executor
TestInsertIgnore – executor
TestIssue10402 – executor
TestStringtoDecimal – executor
TestIssue17745 – executor
TestShowWarnings – showtest_test
TestIssue19892 – expression
TestConvertToBit – expression

[zyguan]

/run-unit-test

[sre-bot]

Code Coverage Details: https://codecov.io/github/pingcap/tidb/commit/5fba098f3daf89a9ef928ca1086061969298c421

[zyguan]

Please fix the following failed integration tests

Fixed, @tangenta @xhebox PTAL.

[zyguan]

/merge

[ti-chi-bot]

@zyguan: /merge is only allowed for the committers, you can assign this pull request to the committer in list by filling /assign @committer in the comment to help merge this pull request.

In response to this:

/merge

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[xhebox]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 3b6487e

[ti-srebot]

cherry pick to release-5.4 in PR #36929

[ti-srebot]

cherry pick to release-6.0 in PR #36930

[ti-srebot]

cherry pick to release-6.1 in PR #36931

[ti-srebot]

cherry pick to release-6.2 in PR #36932

[sre-bot]

TiDB MergeCI notify

🔴 Bad News! [1] CI still failing after this pr merged.
These failed integration tests don't seem to be introduced by the current PR.

CI Name	Result	Duration	Compare with Parent commit
idc-jenkins-ci-tidb/common-test	🔴 failed 2, success 9, total 11	15 min	Existing failure
idc-jenkins-ci/integration-cdc-test	🟢 all 36 tests passed	28 min	Existing passed
idc-jenkins-ci-tidb/integration-common-test	🟢 all 17 tests passed	17 min	Existing passed
idc-jenkins-ci-tidb/sqllogic-test-2	🟢 all 28 tests passed	8 min 0 sec	Existing passed
idc-jenkins-ci-tidb/sqllogic-test-1	🟢 all 26 tests passed	6 min 29 sec	Existing passed
idc-jenkins-ci-tidb/tics-test	🟢 all 1 tests passed	6 min 20 sec	Existing passed
idc-jenkins-ci-tidb/integration-ddl-test	🟢 all 6 tests passed	5 min 30 sec	Existing passed
idc-jenkins-ci-tidb/mybatis-test	🟢 all 1 tests passed	4 min 12 sec	Existing passed
idc-jenkins-ci-tidb/integration-compatibility-test	🟢 all 1 tests passed	4 min 10 sec	Existing passed
idc-jenkins-ci-tidb/plugin-test	🟢 build success, plugin test success	4min	Existing passed