Le 03/11/2014 20:57, Luc Maisonobe a écrit : > Le 03/11/2014 12:09, Gilles a écrit : >> Hi. > > Hi Gilles, > >> >> Three posts such as the following were sent to this ML: >> >>> Merge branch 'master' of >>> https://git-wip-us.apache.org/repos/asf/commons-math >>> >>> >>> Project: http://git-wip-us.apache.org/repos/asf/commons-math/repo >>> Commit: >>> http://git-wip-us.apache.org/repos/asf/commons-math/commit/7df65a5d >>> Tree: http://git-wip-us.apache.org/repos/asf/commons-math/tree/7df65a5d >>> Diff: http://git-wip-us.apache.org/repos/asf/commons-math/diff/7df65a5d >>> >>> Branch: refs/heads/master >>> Commit: 7df65a5ddf59b564af1d753b89d30f8dc33a2c5d >>> Parents: 4a6bf54 45ae5c7 >>> Author: Gilles <er...@apache.org> >>> Authored: Sun Nov 2 23:22:11 2014 +0100 >>> Committer: Gilles <er...@apache.org> >>> Committed: Sun Nov 2 23:22:11 2014 +0100 >>> >>> >>> ---------------------------------------------------------------------- >>> src/changes/changes.xml | 3 + >>> .../math3/ode/ContinuousOutputModel.java | 71 >>> ++++++++++++++++++-- >>> .../math3/ode/sampling/StepInterpolator.java | 28 ++++++-- >>> .../math3/ode/ContinuousOutputModelTest.java | 21 ++++-- >>> 4 files changed, 105 insertions(+), 18 deletions(-) >>> >>> ---------------------------------------------------------------------- >> >> They seem like a report on what happened on my local repository so >> that I could commit local changes after the main repository had been >> updated. >> This kind of message looks utterly useless and distracts from those >> that report actual changes to the main repository. >> >> Don't you think that they should be filtered out? > > I'm not sure. > >> If not, can you explain their purpose? > > I think this is due to the very strict handling of history by Git. Each > commit is completely linked with its parent and the commit hash takes > this link into account. In other words, the commit does not depend only > on what it contains but also on what point in the history it is applied to. > > A side effect is that if the main repository history is: > > A -> B -> C -> D > > and at this point you clone it and start working on a local change, your > local history will be as follows: > > A -> B -> C -> D > | > -> G1 -> G2 -> G3 > > Then, someone else pushes other modifications on the main repository, > which still only has D as its head, so the main repository history becomes: > > A -> B -> C -> D -> E -> F > > On your local clone, you merge these changes and get: > > A -> B -> C -> D -> E -> F--------- > | | > -> G1 -> G2 -> G3 --> G4 > > where G4 is a merge. > > This can occur several time. > > When you finally push your work back to the repository, it pushes the > full history of your current head to become the new head. So you will > see G1, G2, G3 (and this is really what you want, as it means you can do > small incremental changes without losing anything), but it will also see > some merge about thing you did not do yourself.
For the record, there is a way to completely avoid this merge, by replacing the branch with a new one "replaying" the commits G1, G2 ... on top of F instead of their original start commit which was D. This is done using "git rebase". After a rebase, G1 parent becomes F and the merge is done in a simpler linear way, this is what Git calls a "fast-forward" merge. However, I would not recommend using rebase, especially to someone not already accustomed to Git. best regards, Luc > > Here, commit 7df65 is a merge commit. It does not really include any > change, but only records the fact the current point in history has two > parents as it is the result of merging (here without any conflict) > commits 4a6bf54 (which was also a previous merge in your local history) > and 45ae5c7 (which was the head of main repository). If you follow the > link "Diff" from the message, you will see this commit is labeled as > "trivial merge" without any modified files associated. > > Perhaps you could ask INFRA why the message from merge commit 7df65 does > contain the list of files modified by one of its parent commit (here > 45ae5c7) instead of an empty list as there was no conflict between the > merge. If I run "git show --format=fuller 7df65" to have an extensive > description of the commit, I only get: > > commit 7df65a5ddf59b564af1d753b89d30f8dc33a2c5d > Merge: 4a6bf54 45ae5c7 > Author: Gilles <er...@apache.org> > AuthorDate: Sun Nov 2 23:22:11 2014 +0100 > Commit: Gilles <er...@apache.org> > CommitDate: Sun Nov 2 23:22:11 2014 +0100 > > Merge branch 'master' of > https://git-wip-us.apache.org/repos/asf/commons-math > > Also looking at the list of files changed, it seems it includes files > from several commits in the branches, not only the last changed files: > commit 45ae5c7 only changed ContinuousOutputModel.java and not > StepInterpolator.java which was changed by an earlier commit in the > history. So I really don't know how the files list is created and put > into the message. Perhaps INFRA knows. > > best regards, > Luc > >> >> Regards, >> Gilles >> >> >> --------------------------------------------------------------------- >> To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org >> For additional commands, e-mail: dev-h...@commons.apache.org >> >> >> > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org > For additional commands, e-mail: dev-h...@commons.apache.org > > > --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org For additional commands, e-mail: dev-h...@commons.apache.org
