fix(core): synth output is not valid YAML when using policy validation#37597
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fix(core): synth output is not valid YAML when using policy validation#37597
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Tests were asserting on consoleLogMock for messages that now go to console.error. Updated all test assertions to read from consoleErrorMock with adjusted call indices since 'Performing Policy Validations' is now also on stderr (index 0), shifting the report to index 1.
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Closes #25331
Reason for this change
According to synth docs, CDK is supposed to support
cdk synth > template.ymlWhen using policy validation, some outputs are being written to stdout. This makes the stdout not valid YAML (in situations where we specify a single stack and thus write the YAML template to stdout).
Description of changes
Instead of writing to stdout, we write to stderr. This is a pattern established elsewhere in CDK where we reserve stdout for the YAML template. No new tests; only the output channel is being changed and is reflected in updated tests.
Checklist
By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license