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JavaScript@langchain/coreutilstestingStreamMatchers

Interface●Since v1.2

StreamMatchers

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interface StreamMatchers

Methods

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toHaveStreamOutput→ R

Asserts that the final streamed output message matches the expected fields.

toHaveStreamReasoning→ R

Asserts that the stream resolves to the expected concatenated reasoning text.

toHaveStreamText→ R

Asserts that the stream resolves to the expected concatenated text.

toHaveStreamToolCalls→ R

Asserts that the stream resolves to the expected ordered tool calls.

toHaveStreamUsage→ R

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

Custom assertion helpers for values returned by BaseChatModel.streamEvents().

These matchers consume the stream lazily through the corresponding ChatModelStream promise-backed properties.