test-copies: improve description of the D+G case This will make its role clearer. Differential Revision: https://phab.mercurial-scm.org/D10041

test-copies: improve description of the A+E case This will make its role clearer. Differential Revision: https://phab.mercurial-scm.org/D10040

test-copies: improve description of the B+D case This will make its role clearer. Differential Revision: https://phab.mercurial-scm.org/D10039

test-copies: improve description of the B+C case This will make its role clearer. Differential Revision: https://phab.mercurial-scm.org/D10038

test-copies: improve description of the A+B case This will make its role clearer. Differential Revision: https://phab.mercurial-scm.org/D10037

test-copies: use intermediate variable some commit descriptions Right now, everything mostly says "simple merge", we want to use something a bit more descriptive. Before doing any changes, we do most of the churn. This helps the next sets of changesets to be clearer. Differential Revision: https://phab.mercurial-scm.org/D10036

test-copies: don't use empty file for "same content" cases For main case (using filelog or sidedata), this lead to the following hash change. Changesets: - 01c2f5eabdc4ce2bdee42b5f86311955e6c8f573 → 319179230cc87769ab3a861ebffe7a534ebb3d85 - 01c2f5eabdc4 → 319179230cc8 - c72365ee036fca4fb27fd745459bfb6ea1ac6993 → 6cbc9c2b7b391dd738603173717c601648d3735f - c72365ee036f → 6cbc9c2b7b39 File revision for `f`: - 0dd616bc7ab1a111921d95d76f69cda5c2ac539c → cedeacc5bf5d9b9be4d7f8394d33a5349bb29c6e - 0dd616bc7ab1 → cedeacc5bf5d - eb806e34ef6be4c264effd5933d31004ad15a793 → ffb76cd765422a18759a335d8a81fa2bd455be6b - eb806e34ef6b → ffb76cd76542 - 6da5a2eecb9c833f830b67a4972366d49a9a142c → 08d1ff5926fbd0285cdeb044cbe8ab651687e86a - 6da5a2eecb9c → 08d1ff5926fb File revision for `d`: - 7bded9d9da1f7bf9bf7cbfb24fe1e6ccf68ec440 → ba177bbb45ea930ee48469a55d40224537bd57a9 For the "extra in changeset" case we get the following change for file `d`: - 68d5bca9df0577b6bc2ea30ca724e13ead60da81 → b894de5c94aadcb4894ea7c358389819c27fbcce - 68d5bca9df05 → b894de5c94aa - b80de5d138758541c5f05265ad144ab9fa86d1db → 56647659eff080e06e45c18ea9e848836dadea71 - b80de5d13875 → 56647659eff0

test-copies: reinstall initial identical (empty) files for chained copied This effectively back out changeset deeb215be337. Changeset deeb215be33 does not really include a justification for its change and make mes uncomfortable. I have been thinking about it and they are two options: - either having empty/full files does not make a difference, and deeb215be337 is a gratuitous changes. - either having empty/full files do make a difference and deeb215be33 silently change the test coverage. In such situation if we want the "not empty" case to be tested, we should add new cases to cover them In practice, we know that the "file content did not change, but merge still need to create a new filenode" case exists (for example if merging result in similar content but both parent of the file need to be recorded), and that such case are easy to miss/mess-up in the tests. Having all the file using the same (empty) content was done on purpose to increase the coverage of such corner case. As a result I am reinstalling the previous test situation. To increase the coverage of some case involving content-merge in test-copies-chain-merge.t, we will add a new, dedicated, cases later in this series, once various cleanup and test improvement have been set in place. This changeset starts with reinstalling the previous situation as (1) it is more fragile, so I am more confided getting it back in the initial situation, (2) I have specific test further down the line that are base on these one. The next changeset will slightly alter the test to use non-empty files for these tests (with identical content). It should help to make the initial intent "merge file with identical content" clearer. I am still using a two steps (backout, then change content) approach to facilitate careful validation of the output change. Doing so has a large impact on the output of the "copy info in changeset extra" variant added in 5e72827dae1e (2 changesets after deeb215be33). It seems to highlight various breakage when merge without content change are involved, this is a good example of why we want to explicitly test theses cases. Because the different -do- matters a lot. Fixing the "copy info in changeset extra" is not a priority here. Because (1) this changeset does not break anything, it only highlight that they were always broken. (2) the only people using "copy info in changeset extra" do not have merge. Differential Revision: https://phab.mercurial-scm.org/D9587