git/diff.c, branch v2.27.0

Merge branch 'jt/avoid-prefetch-when-able-in-diff'

2020-04-28T22:50:04Z

"git diff" in a partial clone learned to avoid lazy loading blob objects in more casese when they are not needed. * jt/avoid-prefetch-when-able-in-diff: diff: restrict when prefetching occurs diff: refactor object read diff: make diff_populate_filespec_options struct promisor-remote: accept 0 as oid_nr in function

diff: restrict when prefetching occurs

2020-04-07T23:09:29Z

Commit 7fbbcb21b1 ("diff: batch fetching of missing blobs", 2019-04-08) optimized "diff" by prefetching blobs in a partial clone, but there are some cases wherein blobs do not need to be prefetched. In these cases, any command that uses the diff machinery will unnecessarily fetch blobs. diffcore_std() may read blobs when it calls the following functions: (1) diffcore_skip_stat_unmatch() (controlled by the config variable diff.autorefreshindex) (2) diffcore_break() and diffcore_merge_broken() (for break-rewrite detection) (3) diffcore_rename() (for rename detection) (4) diffcore_pickaxe() (for detecting addition/deletion of specified string) Instead of always prefetching blobs, teach diffcore_skip_stat_unmatch(), diffcore_break(), and diffcore_rename() to prefetch blobs upon the first read of a missing object. This covers (1), (2), and (3): to cover the rest, teach diffcore_std() to prefetch if the output type is one that includes blob data (and hence blob data will be required later anyway), or if it knows that (4) will be run. Helped-by: Jeff King Signed-off-by: Jonathan Tan Signed-off-by: Junio C Hamano

diff: refactor object read

2020-04-07T23:09:29Z

Refactor the object reads in diff_populate_filespec() to have the first object read not be in an if/else branch, because in a future patch, a retry will be added to that first object read. Signed-off-by: Jonathan Tan Signed-off-by: Junio C Hamano

diff: make diff_populate_filespec_options struct

2020-04-07T23:09:29Z

The behavior of diff_populate_filespec() currently can be customized through a bitflag, but a subsequent patch requires it to support a non-boolean option. Replace the bitflag with an options struct. Signed-off-by: Jonathan Tan Signed-off-by: Junio C Hamano

promisor-remote: accept 0 as oid_nr in function

2020-04-02T19:42:32Z

There are 3 callers to promisor_remote_get_direct() that first check if the number of objects to be fetched is equal to 0. Fold that check into promisor_remote_get_direct(), and in doing so, be explicit as to what promisor_remote_get_direct() does if oid_nr is 0 (it returns 0, success, immediately). Signed-off-by: Jonathan Tan Signed-off-by: Junio C Hamano

convert: provide additional metadata to filters

2020-03-16T18:37:02Z

Now that we have the codebase wired up to pass any additional metadata to filters, let's collect the additional metadata that we'd like to pass. The two main places we pass this metadata are checkouts and archives. In these two situations, reading HEAD isn't a valid option, since HEAD isn't updated for checkouts until after the working tree is written and archives can accept an arbitrary tree. In other situations, HEAD will usually reflect the refname of the branch in current use. We pass a smaller amount of data in other cases, such as git cat-file, where we can really only logically know about the blob. This commit updates only the parts of the checkout code where we don't use unpack_trees. That function and callers of it will be handled in a future commit. In the archive code, we leak a small amount of memory, since nothing we pass in the archiver argument structure is freed. Signed-off-by: brian m. carlson Signed-off-by: Junio C Hamano

convert: permit passing additional metadata to filter processes

2020-03-16T18:37:02Z

There are a variety of situations where a filter process can make use of some additional metadata. For example, some people find the ident filter too limiting and would like to include the commit or the branch in their smudged files. This information isn't available during checkout as HEAD hasn't been updated at that point, and it wouldn't be available in archives either. Let's add a way to pass this metadata down to the filter. We pass the blob we're operating on, the treeish (preferring the commit over the tree if one exists), and the ref we're operating on. Note that we won't pass this information in all cases, such as when renormalizing or when we're performing diffs, since it doesn't make sense in those cases. The data we currently get from the filter process looks like the following: command=smudge pathname=git.c 0000 With this change, we'll get data more like this: command=smudge pathname=git.c refname=refs/tags/v2.25.1 treeish=c522f061d551c9bb8684a7c3859b2ece4499b56b blob=7be7ad34bd053884ec48923706e70c81719a8660 0000 There are a couple things to note about this approach. For operations like checkout, treeish will always be a commit, since we cannot check out individual trees, but for other operations, like archive, we can end up operating on only a particular tree, so we'll provide only a tree as the treeish. Similar comments apply for refname, since there are a variety of cases in which we won't have a ref. This commit wires up the code to print this information, but doesn't pass any of it at this point. In a future commit, we'll have various code paths pass the actual useful data down. Signed-off-by: brian m. carlson Signed-off-by: Junio C Hamano

Merge branch 'mt/use-passed-repo-more-in-funcs'

2020-02-14T20:54:22Z

Some codepaths were given a repository instance as a parameter to work in the repository, but passed the_repository instance to its callees, which has been cleaned up (somewhat). * mt/use-passed-repo-more-in-funcs: sha1-file: allow check_object_signature() to handle any repo sha1-file: pass git_hash_algo to hash_object_file() sha1-file: pass git_hash_algo to write_object_file_prepare() streaming: allow open_istream() to handle any repo pack-check: use given repo's hash_algo at verify_packfile() cache-tree: use given repo's hash_algo at verify_one() diff: make diff_populate_filespec() honor its repo argument

diff: move diff.wsErrorHighlight to "basic" config

2020-01-31T20:01:19Z

We parse diff.wsErrorHighlight in git_diff_ui_config(), meaning that it doesn't take effect for plumbing commands, only for porcelains like git-diff itself. This is mildly annoying as it means scripts like add--interactive, which produce a user-visible diff with color, don't respect the option. We could teach that script to parse the config and pass it along as --ws-error-highlight to the diff plumbing. But there's a simpler solution. It should be reasonably safe for plumbing to respect this option, as it only kicks in when color is otherwise enabled. And anybody parsing colorized output must already deal with the fact that color.diff.* may change the exact output they see; those options have been part of git_diff_basic_config() since its inception in 9a1805a872 (add a "basic" diff config callback, 2008-01-04). So we can just move it to the "basic" config, which fixes add--interactive, along with any other script in the same boat, with a very low risk of hurting any plumbing users. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

diff: make diff_populate_filespec() honor its repo argument

2020-01-31T18:45:39Z

diff_populate_filespec() takes a struct repository argument but it doesn't get passed down to read_object_file(). Signed-off-by: Matheus Tavares Signed-off-by: Junio C Hamano