Keeping it separate allows ensuring the test works easily: just revert the fix keeping only the patch for the test and make sure the test fails. My workflow te

Keeping it separate allows ensuring the test works easily: just revert the fix keeping only the patch for the test and make sure the test fails. My workflow tend to be to keep them separate, and write a big description in the merge commit rather than the individual commits (those have a small description of the local change). There's tradeoffs to both approach though, and as you mention, it's easier to keep track of the provenance of a fix in the git blame when it's unified in a single commit message.