Mocking

as-test supports a few different kinds of controlled test substitution:

• local function mocking with mockFn(...)
• import-path mocking with mockImport(...)
• stable captured values with snapshotFn(...)

Use mocks selectively. The value of as-test is that you can often run against the real runtime and only replace the edge you actually need to control.

Start Here

• Function Mocks
• Import Mocks
• Stable Values With snapshotFn

When To Mock

Good reasons to mock:

• host imports
• clocks and random sources
• hard-to-reproduce runtime failures
• expensive or noisy dependencies
• values that should stay fixed for one test run