The test itself is kind of tricky, because the purpose is to verify import functionality on all supported shells, but not all shells have enough introspection features.
Hence, it cannot cannot succeed on Debian: it reloies on declare -f, which is not available in default sh mode interpeter there (dash).
Few ideas how to work around this: Explicitly call bash in sh mode, use different way of verification or skip particular test parts for Debian. Solution should be a combination of multiple approaches.
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