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JavaScript@langchain/coretestingStreamMatcherstoHaveStreamUsage

Method●Since v1.2

toHaveStreamUsage

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toHaveStreamUsage(expected: StreamUsageExpectation): R

View source on GitHub

Parameters

Name	Type	Description
`expected`*	`StreamUsageExpectation`	A partial usage metadata object expected from `ChatModelStream.usage`.

Asserts that the stream resolves to usage metadata matching the expected fields.