Re: Requirements for integrating a new git subcommand
Eric S. Raymond: and (b) include the removal of import-directories.perl in my integration patch. Yes, please. -- \\// Peter - http://www.softwolves.pp.se/ -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Requirements for integrating a new git subcommand
Junio C Hamano : > "Eric S. Raymond" writes: > > > While the weave operation can build a commit graph with any structure > > desired, an important restriction of the inverse (unraveling) > > operation is that it operates on *master branches only*. The unravel > > operation discards non-master-branch content, emitting a warning > > to standard error when it has to do so. > > Imagine that I have a simple four-commit diamond: > > I---A > \ \ > B---M > > where Amy and Bob forked the initial commit made by Ian and created > one commit each, and their branches were merged into one 'master' > branch by a merge commit made by Mac. How many state snapshots will > I see when I ask you to unravel this? Three, or four? You will see four tree states. I have managed to remove the master-branch-only restriction. > As to the procedural stuff, I think others have sufficiently > answered already. If I may add something, a new stuff typically > start its life in contrib/ before it proves to be useful. Thank you, I have submitted a documentation patch which folds in the on-list discussion. As a separate point...are you requesting that I submit my integration patch to drop git-weave in contrib? If so, I will of course comply. But I will point out that git-weave is not a half-thought out experiment; it is fully documented and has a functional test. The case for its usefulness is bolstered by one previous contrib script, which the author has agreed to retire in favor of git-weave. -- http://www.catb.org/~esr/";>Eric S. Raymond -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Requirements for integrating a new git subcommand
"Eric S. Raymond" writes: > While the weave operation can build a commit graph with any structure > desired, an important restriction of the inverse (unraveling) > operation is that it operates on *master branches only*. The unravel > operation discards non-master-branch content, emitting a warning > to standard error when it has to do so. Imagine that I have a simple four-commit diamond: I---A \ \ B---M where Amy and Bob forked the initial commit made by Ian and created one commit each, and their branches were merged into one 'master' branch by a merge commit made by Mac. How many state snapshots will I see when I ask you to unravel this? Three, or four? If you are going to give me all four states, then I do not understand why this needs to be limited to the master branch only. Even if you start from a single commit at the tip of 'master', once you hit a merge, you will need to follow all of two (or more) paths to dig down to the root(s), so supporting to start digging from more than one commit is not all that different. If you are going to give me only three states, following the first parent ancestry chain, then the description needs to state it more clearly. I am not saying first-parent-only history is useless, but the user needs to know that merges are flattened in the unraveled result and the resulting history becomes linear, following the first parent ancestry chain of the original history (if that is what the tool does) before deciding if this tool matches what she needs. As to the procedural stuff, I think others have sufficiently answered already. If I may add something, a new stuff typically start its life in contrib/ before it proves to be useful. -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Requirements for integrating a new git subcommand
On Thu, Nov 22, 2012 at 11:11 PM, Eric S. Raymond wrote: > Shawn Pearce : >> [Lots of helpful stuff ended by] >> > 4. How does "git help" work? That is, how is a subcommand expected >> > to know when it is being called to export its help text? >> >> IIRC "git help foo" runs "man git-foo". > > OK, that makes sense. "git help" can also launch a browser to display the HTML version of the man page. It is looking for man pages and HTML docs in the paths given by "git --man-path" and "git --html-path". Cheers, Christian. -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Requirements for integrating a new git subcommand
Shawn Pearce : > Nope, it just has to be executable. We don't have any current Python > code. IIRC the last Python code was the implementation of > git-merge-recursive, which was ported to C many years ago. This turns out not to be quite true. The tree currently includes two Python scripts, a Perforce importer and a test helper. I'm in he process of writing up a document on command integration based on your answers. I will submit it for incusion in the tree shortly. -- http://www.catb.org/~esr/";>Eric S. Raymond -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Requirements for integrating a new git subcommand
Michael J Gruber : > Regarding git-weave, I'm wondering (without having looked at the code) > how this relates to git-archiv and git-fast-import/export, i.e. how much > this leverages existing infrastructure rather than reinventing the > wheel. Do your "trees" correspond to a "git tree"? The unravel operation of git-weave is something like running git-archive on every revision and saving the results in sequentially-named directories, except that it also produces a metadata file that allows the operation to be inverted. So it is strictly more powerful. The weave operation could be implemented using git fast-import, which I am quite intimately familiar with from having written reposurgeon. Functionally, the difference is that it would be a PITA to patch a fast-import stream to insert or modify or remove revisions in the middle, because the content of any given revision is in blobs that can stretch arbitrarily far back from its commit and are shared with other revisions. With git-weave tree-sequences these operations are easy and safe. > Again, without having looked at the code, it seems to me that exploding > blob and tree objects might give you a structure not much unlike > weave's, and your instruction sheet resembles that of fast-import quite > a bit (plus date fill-in etc.). The weave log resembles an import stream, yes - that's because they have to capture the same data ontology. One major difference is that weave logs are designed to be generated and edited by humans. > One could even dream about implementing this as a remote helper instead... What is a "remote helper" in this context? -- http://www.catb.org/~esr/";>Eric S. Raymond -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Requirements for integrating a new git subcommand
Peter Krefting : > I was just about to say that the import direction of this seems to > fill the same need as contrib/fast-import/import-directories.perl > that I submitted a few years back. Yours was the closest in functionality, yes. > Your version seems only to be able to import a linear history, > however, my tool does support creating merge commits (basically, the > history I had to import was very messy and contained a lot of > snapshot directories having been worked on in parallel). git-weave can *weave* (import) a sequence with merge commits, as your tool can. What it can't do is unravel a nonlinear repo into a tree sequence that will round-trip through the weave operation. (Though I thought of a way I might be able to fix that last night.) > Anyway, my sentiment is that if you can add support for merges in > you weave tool, then I am very much for removing my old script from > the repository. The support is there. I will take this as direction to (a) add a test load demonstrating this, and (b) include the removal of import-directories.perl in my integration patch. -- http://www.catb.org/~esr/";>Eric S. Raymond -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Requirements for integrating a new git subcommand
Eric S. Raymond: git-weave(1) Yes, there are scripts in contrib that do similar things. I was just about to say that the import direction of this seems to fill the same need as contrib/fast-import/import-directories.perl that I submitted a few years back. Your version seems only to be able to import a linear history, however, my tool does support creating merge commits (basically, the history I had to import was very messy and contained a lot of snapshot directories having been worked on in parallel). (b) I am shipping it with a functional test, Hmm, indeed. I have been thinking of trying to wrap up the test suite I have locally into something that could work within the Git testing framework, but haven't found the time to or energy for so far. Anyway, my sentiment is that if you can add support for merges in you weave tool, then I am very much for removing my old script from the repository. -- \\// Peter - http://www.softwolves.pp.se/ -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Requirements for integrating a new git subcommand
Eric S. Raymond venit, vidit, dixit 22.11.2012 23:11: > Shawn Pearce : >> [Lots of helpful stuff ended by] >>> 4. How does "git help" work? That is, how is a subcommand expected >>> to know when it is being called to export its help text? >> >> IIRC "git help foo" runs "man git-foo". > > OK, that makes sense. > >>> 5. I don't see any extensions written in Python. Are there any special >>> requirements or exclusions for Python scripts? >> >> Nope, it just has to be executable. We don't have any current Python >> code. IIRC the last Python code was the implementation of >> git-merge-recursive, which was ported to C many years ago. We avoid >> Python because it is not on every platform where Git is installed. Yes >> Python is very portable and can be installed in many places, but we >> prefer not to make it a requirement. > > I find that odd. You avoid Python but use shellscripts? *blink* > > One would think shellscripts were a much more serious portability problem. Different versions of python can be a mess to deal with, also, at least with respect to standard modules being "standard" or not for a specific version. In any case, the point is that we try to avoid *additional* dependencies. Shell and perl are given with the status quo. That being said, we also have remote helpers in python. The testsuite can run tests depending on the availability of python. Regarding git-weave, I'm wondering (without having looked at the code) how this relates to git-archiv and git-fast-import/export, i.e. how much this leverages existing infrastructure rather than reinventing the wheel. Do your "trees" correspond to a "git tree"? Again, without having looked at the code, it seems to me that exploding blob and tree objects might give you a structure not much unlike weave's, and your instruction sheet resembles that of fast-import quite a bit (plus date fill-in etc.). One could even dream about implementing this as a remote helper instead... Michael -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Requirements for integrating a new git subcommand
Shawn Pearce : > [Lots of helpful stuff ended by] > > 4. How does "git help" work? That is, how is a subcommand expected > > to know when it is being called to export its help text? > > IIRC "git help foo" runs "man git-foo". OK, that makes sense. > > 5. I don't see any extensions written in Python. Are there any special > > requirements or exclusions for Python scripts? > > Nope, it just has to be executable. We don't have any current Python > code. IIRC the last Python code was the implementation of > git-merge-recursive, which was ported to C many years ago. We avoid > Python because it is not on every platform where Git is installed. Yes > Python is very portable and can be installed in many places, but we > prefer not to make it a requirement. I find that odd. You avoid Python but use shellscripts? *blink* One would think shellscripts were a much more serious portability problem. -- http://www.catb.org/~esr/";>Eric S. Raymond -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Requirements for integrating a new git subcommand
On Wed, Nov 21, 2012 at 9:30 PM, Eric S. Raymond wrote: > I have completed work on git-weave (the tool I had called 'gitpacker' in some > previous postings). I want to submit a patch that integrates it into git; > in hopes of smoothing the process I have some technical and procedural > questions. ... > Now *my* questions: > > 1. I have a round-trip test for the tool that I can very easily adapt > to speak TAP. To function, the test will require a small linear > history to operate on in the form of an import-stream file (so the > result of round-tripping through a weave-unravel can be diffed against > the original). Does the distribution include any test repos? If > so, where can I find them? No. We create the repositories from scratch using a series of commands. If you look at the test library the environment is set in a predictable way so the author, committer and timestamps are all set to a single well known value, allowing Git to create a commit that is reproducible on all platforms. A test_tick function is used in the scripts to move the clock, allowing different times to be used. For an example see t7502-commit.sh, or really any script in that directory. > 2. I understand that a "git foo" command is typically implemented > as "git-foo" binary or script in /usr/lib/git-core. What I don't > know is what the other interfacing requirements are. Are they > documented anywhere? In particular... Nope. "git foo" will invoke "git-foo" with GIT_DIR set in the environment, so you know what repository to act against, and so does any git command you recursively invoke. Other than that there really aren't any interface requirements. Your program is executed with whatever arguments the caller gave you. Its pretty simple UNIX stuff. :-) > 3. Is there any registration protocol other than simply installing > the extension in the subcommand library? Nope. Running "git whatever-this-is-i-have-no-idea" will try to execute "git-whatever-this-is-i-have-no-idea" via $PATH, after adding /usr/lib/git-core to the front of $PATH. Its pretty simple actually. If your standard C library can find the program in $PATH its run, if it can't find it, it dies. > 4. How does "git help" work? That is, how is a subcommand expected > to know when it is being called to export its help text? IIRC "git help foo" runs "man git-foo". > 5. I don't see any extensions written in Python. Are there any special > requirements or exclusions for Python scripts? Nope, it just has to be executable. We don't have any current Python code. IIRC the last Python code was the implementation of git-merge-recursive, which was ported to C many years ago. We avoid Python because it is not on every platform where Git is installed. Yes Python is very portable and can be installed in many places, but we prefer not to make it a requirement. -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html