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diff --git a/third_party/git/Documentation/RelNotes/2.9.0.txt b/third_party/git/Documentation/RelNotes/2.9.0.txt new file mode 100644 index 000000000000..b61d36712fa7 --- /dev/null +++ b/third_party/git/Documentation/RelNotes/2.9.0.txt @@ -0,0 +1,512 @@ +Git 2.9 Release Notes +===================== + +Backward compatibility notes +---------------------------- + +The end-user facing Porcelain level commands in the "git diff" and +"git log" family by default enable the rename detection; you can still +use "diff.renames" configuration variable to disable this. + +Merging two branches that have no common ancestor with "git merge" is +by default forbidden now to prevent creating such an unusual merge by +mistake. + +The output formats of "git log" that indents the commit log message by +4 spaces now expands HT in the log message by default. You can use +the "--no-expand-tabs" option to disable this. + +"git commit-tree" plumbing command required the user to always sign +its result when the user sets the commit.gpgsign configuration +variable, which was an ancient mistake, which this release corrects. +A script that drives commit-tree, if it relies on this mistake, now +needs to read commit.gpgsign and pass the -S option as necessary. + + +Updates since v2.8 +------------------ + +UI, Workflows & Features + + * Comes with git-multimail 1.3.1 (in contrib/). + + * The end-user facing commands like "git diff" and "git log" + now enable the rename detection by default. + + * The credential.helper configuration variable is cumulative and + there is no good way to override it from the command line. As + a special case, giving an empty string as its value now serves + as the signal to clear the values specified in various files. + + * A new "interactive.diffFilter" configuration can be used to + customize the diff shown in "git add -i" sessions. + + * "git p4" now allows P4 author names to be mapped to Git author + names. + + * "git rebase -x" can be used without passing "-i" option. + + * "git -c credential.<var>=<value> submodule" can now be used to + propagate configuration variables related to credential helper + down to the submodules. + + * "git tag" can create an annotated tag without explicitly given an + "-a" (or "-s") option (i.e. when a tag message is given). A new + configuration variable, tag.forceSignAnnotated, can be used to tell + the command to create signed tag in such a situation. + + * "git merge" used to allow merging two branches that have no common + base by default, which led to a brand new history of an existing + project created and then get pulled by an unsuspecting maintainer, + which allowed an unnecessary parallel history merged into the + existing project. The command has been taught not to allow this by + default, with an escape hatch "--allow-unrelated-histories" option + to be used in a rare event that merges histories of two projects + that started their lives independently. + + * "git pull" has been taught to pass the "--allow-unrelated-histories" + option to underlying "git merge". + + * "git apply -v" learned to report paths in the patch that were + skipped via --include/--exclude mechanism or being outside the + current working directory. + + * Shell completion (in contrib/) updates. + + * The commit object name reported when "rebase -i" stops has been + shortened. + + * "git worktree add" can be given "--no-checkout" option to only + create an empty worktree without checking out the files. + + * "git mergetools" learned to drive ExamDiff. + + * "git pull --rebase" learned "--[no-]autostash" option, so that + the rebase.autostash configuration variable set to true can be + overridden from the command line. + + * When "git log" shows the log message indented by 4-spaces, the + remainder of a line after a HT does not align in the way the author + originally intended. The command now expands tabs by default to help + such a case, and allows the users to override it with a new option, + "--no-expand-tabs". + + * "git send-email" now uses a more readable timestamps when + formulating a message ID. + + * "git rerere" can encounter two or more files with the same conflict + signature that have to be resolved in different ways, but there was + no way to record these separate resolutions. + + * "git p4" learned to record P4 jobs in Git commit that imports from + the history in Perforce. + + * "git describe --contains" often made a hard-to-justify choice of + tag to name a given commit, because it tried to come up + with a name with smallest number of hops from a tag, causing an old + commit whose close descendant that is recently tagged were not + described with respect to an old tag but with a newer tag. It did + not help that its computation of "hop" count was further tweaked to + penalize being on a side branch of a merge. The logic has been + updated to favor using the tag with the oldest tagger date, which + is a lot easier to explain to the end users: "We describe a commit + in terms of the (chronologically) oldest tag that contains the + commit." + + * "git clone" learned the "--shallow-submodules" option. + + * HTTP transport clients learned to throw extra HTTP headers at the + server, specified via http.extraHeader configuration variable. + + * The "--compaction-heuristic" option to "git diff" family of + commands enables a heuristic to make the patch output more readable + by using a blank line as a strong hint that the contents before and + after it belong to logically separate units. It is still + experimental. + + * A new configuration variable core.hooksPath allows customizing + where the hook directory is. + + * An earlier addition of "sanitize_submodule_env" with 14111fc4 (git: + submodule honor -c credential.* from command line, 2016-02-29) + turned out to be a convoluted no-op; implement what it wanted to do + correctly, and stop filtering settings given via "git -c var=val". + + * "git commit --dry-run" reported "No, no, you cannot commit." in one + case where "git commit" would have allowed you to commit, and this + improves it a little bit ("git commit --dry-run --short" still does + not give you the correct answer, for example). This is a stop-gap + measure in that "commit --short --dry-run" still gives an incorrect + result. + + * The experimental "multiple worktree" feature gains more safety to + forbid operations on a branch that is checked out or being actively + worked on elsewhere, by noticing that e.g. it is being rebased. + + * "git format-patch" learned a new "--base" option to record what + (public, well-known) commit the original series was built on in + its output. + + * "git commit" learned to pay attention to the "commit.verbose" + configuration variable and act as if the "--verbose" option + was given from the command line. + + * Updated documentation gives hints to GMail users with two-factor + auth enabled that they need app-specific-password when using + "git send-email". + + * The manpage output of our documentation did not render well in + terminal; typeset literals in bold by default to make them stand + out more. + + * The mark-up in the top-level README.md file has been updated to + typeset CLI command names differently from the body text. + + +Performance, Internal Implementation, Development Support etc. + + * The embedded args argv-array in the child process is used to build + the command line to run pack-objects instead of using a separate + array of strings. + + * A test for tags has been restructured so that more parts of it can + easily be run on a platform without a working GnuPG. + + * The startup_info data, which records if we are working inside a + repository (among other things), are now uniformly available to Git + subcommand implementations, and Git avoids attempting to touch + references when we are not in a repository. + + * The command line argument parser for "receive-pack" has been + rewritten to use parse-options. + + * A major part of "git submodule update" has been ported to C to take + advantage of the recently added framework to run download tasks in + parallel. Other updates to "git submodule" that move pieces of + logic to C continues. + + * Rename bunch of tests on "git clone" for better organization. + + * The tests that involve running httpd leaked the system-wide + configuration in /etc/gitconfig to the tested environment. + + * Build updates for MSVC. + + * The repository set-up sequence has been streamlined (the biggest + change is that there is no longer git_config_early()), so that we + do not attempt to look into refs/* when we know we do not have a + Git repository. + + * Code restructuring around the "refs" API to prepare for pluggable + refs backends. + + * Sources to many test helper binaries and the generated helpers + have been moved to t/helper/ subdirectory to reduce clutter at the + top level of the tree. + + * Unify internal logic between "git tag -v" and "git verify-tag" + commands by making one directly call into the other. + + * "merge-recursive" strategy incorrectly checked if a path that is + involved in its internal merge exists in the working tree. + + * The test scripts for "git p4" (but not "git p4" implementation + itself) has been updated so that they would work even on a system + where the installed version of Python is python 3. + + * As nobody maintains our in-tree git.spec.in and distros use their + own spec file, we stopped pretending that we support "make rpm". + + * Move from "unsigned char[20]" to "struct object_id" continues. + + * The code for warning_errno/die_errno has been refactored and a new + error_errno() reporting helper is introduced. + (merge 1da045f nd/error-errno later to maint). + + * Running tests with '-x' option to trace the individual command + executions is a useful way to debug test scripts, but some tests + that capture the standard error stream and check what the command + said can be broken with the trace output mixed in. When running + our tests under "bash", however, we can redirect the trace output + to another file descriptor to keep the standard error of programs + being tested intact. + + * t0040 had too many unnecessary repetitions in its test data. Teach + test-parse-options program so that a caller can tell what it + expects in its output, so that these repetitions can be cleaned up. + + * Add perf test for "rebase -i". + + * Common mistakes when writing gitlink: in our documentation are + found by "make check-docs". + + * t9xxx series has been updated primarily for readability, while + fixing small bugs in it. A few scripted Porcelain commands have + also been updated to fix possible bugs around their use of + "test -z" and "test -n". + + * CI test was taught to run git-svn tests. + + * "git cat-file --batch-all" has been sped up, by taking advantage + of the fact that it does not have to read a list of objects, in two + ways. + + * test updates to make it more readable and maintainable. + (merge e6273f4 es/t1500-modernize later to maint). + + * "make DEVELOPER=1" worked as expected; setting DEVELOPER=1 in + config.mak didn't. + (merge 51dd3e8 mm/makefile-developer-can-be-in-config-mak later to maint). + + * The way how "submodule--helper list" signals unmatch error to its + callers has been updated. + + * A bash-ism "local" has been removed from "git submodule" scripted + Porcelain. + + +Also contains various documentation updates and code clean-ups. + + +Fixes since v2.8 +---------------- + +Unless otherwise noted, all the fixes since v2.8 in the maintenance +track are contained in this release (see the maintenance releases' +notes for details). + + * "git config --get-urlmatch", unlike other variants of the "git + config --get" family, did not signal error with its exit status + when there was no matching configuration. + + * The "--local-env-vars" and "--resolve-git-dir" options of "git + rev-parse" failed to work outside a repository when the command's + option parsing was rewritten in 1.8.5 era. + + * "git index-pack --keep[=<msg>] pack-$name.pack" simply did not work. + + * Fetching of history by naming a commit object name directly didn't + work across remote-curl transport. + + * A small memory leak in an error codepath has been plugged in xdiff + code. + + * strbuf_getwholeline() did not NUL-terminate the buffer on certain + corner cases in its error codepath. + + * "git mergetool" did not work well with conflicts that both sides + deleted. + + * "git send-email" had trouble parsing alias file in mailrc format + when lines in it had trailing whitespaces on them. + + * When "git merge --squash" stopped due to conflict, the concluding + "git commit" failed to read in the SQUASH_MSG that shows the log + messages from all the squashed commits. + + * "git merge FETCH_HEAD" dereferenced NULL pointer when merging + nothing into an unborn history (which is arguably unusual usage, + which perhaps was the reason why nobody noticed it). + + * When "git worktree" feature is in use, "git branch -d" allowed + deletion of a branch that is checked out in another worktree, + which was wrong. + + * When "git worktree" feature is in use, "git branch -m" renamed a + branch that is checked out in another worktree without adjusting + the HEAD symbolic ref for the worktree. + + * "git diff -M" used to work better when two originally identical + files A and B got renamed to X/A and X/B by pairing A to X/A and B + to X/B, but this was broken in the 2.0 timeframe. + + * "git send-pack --all <there>" was broken when its command line + option parsing was written in the 2.6 timeframe. + + * "git format-patch --help" showed `-s` and `--no-patch` as if these + are valid options to the command. We already hide `--patch` option + from the documentation, because format-patch is about showing the + diff, and the documentation now hides these options as well. + + * When running "git blame $path" with unnormalized data in the index + for the path, the data in the working tree was blamed, even though + "git add" would not have changed what is already in the index, due + to "safe crlf" that disables the line-end conversion. It has been + corrected. + + * A change back in version 2.7 to "git branch" broke display of a + symbolic ref in a non-standard place in the refs/ hierarchy (we + expect symbolic refs to appear in refs/remotes/*/HEAD to point at + the primary branch the remote has, and as .git/HEAD to point at the + branch we locally checked out). + + * A partial rewrite of "git submodule" in the 2.7 timeframe changed + the way the gitdir: pointer in the submodules point at the real + repository location to use absolute paths by accident. This has + been corrected. + + * "git commit" misbehaved in a few minor ways when an empty message + is given via -m '', all of which has been corrected. + + * Support for CRAM-MD5 authentication method in "git imap-send" did + not work well. + + * Upcoming OpenSSL 1.1.0 will break compilation by updating a few API + elements we use in imap-send, which has been adjusted for the change. + + * The socks5:// proxy support added back in 2.6.4 days was not aware + that socks5h:// proxies behave differently from socks5:// proxies. + + * "git config" had a codepath that tried to pass a NULL to + printf("%s"), which nobody seems to have noticed. + + * On Cygwin, object creation uses the "create a temporary and then + rename it to the final name" pattern, not "create a temporary, + hardlink it to the final name and then unlink the temporary" + pattern. + + This is necessary to use Git on Windows shared directories, and is + already enabled for the MinGW and plain Windows builds. It also + has been used in Cygwin packaged versions of Git for quite a while. + See http://thread.gmane.org/gmane.comp.version-control.git/291853 + + * "merge-octopus" strategy did not ensure that the index is clean + when merge begins. + + * When "git merge" notices that the merge can be resolved purely at + the tree level (without having to merge blobs) and the resulting + tree happens to already exist in the object store, it forgot to + update the index, which left an inconsistent state that would + break later operations. + + * "git submodule" reports the paths of submodules the command + recurses into, but these paths were incorrectly reported when + the command was not run from the root level of the superproject. + + * The "user.useConfigOnly" configuration variable makes it an error + if users do not explicitly set user.name and user.email. However, + its check was not done early enough and allowed another error to + trigger, reporting that the default value we guessed from the + system setting was unusable. This was a suboptimal end-user + experience as we want the users to set user.name/user.email without + relying on the auto-detection at all. + + * "git mv old new" did not adjust the path for a submodule that lives + as a subdirectory inside old/ directory correctly. + + * "git replace -e" did not honour "core.editor" configuration. + + * "git push" from a corrupt repository that attempts to push a large + number of refs deadlocked; the thread to relay rejection notices + for these ref updates blocked on writing them to the main thread, + after the main thread at the receiving end notices that the push + failed and decides not to read these notices and return a failure. + + * mmap emulation on Windows has been optimized and work better without + consuming paging store when not needed. + + * A question by "git send-email" to ask the identity of the sender + has been updated. + + * UI consistency improvements for "git mergetool". + + * "git rebase -m" could be asked to rebase an entire branch starting + from the root, but failed by assuming that there always is a parent + commit to the first commit on the branch. + + * Fix a broken "p4 lfs" test. + + * Recent update to Git LFS broke "git p4" by changing the output from + its "lfs pointer" subcommand. + + * "git fetch" test t5510 was flaky while running a (forced) automagic + garbage collection. + + * Documentation updates to help contributors setting up Travis CI + test for their patches. + + * Some multi-byte encoding can have a backslash byte as a later part + of one letter, which would confuse "highlight" filter used in + gitweb. + + * "git commit-tree" plumbing command required the user to always sign + its result when the user sets the commit.gpgsign configuration + variable, which was an ancient mistake. Rework "git rebase" that + relied on this mistake so that it reads commit.gpgsign and pass (or + not pass) the -S option to "git commit-tree" to keep the end-user + expectation the same, while teaching "git commit-tree" to ignore + the configuration variable. This will stop requiring the users to + sign commit objects used internally as an implementation detail of + "git stash". + + * "http.cookieFile" configuration variable clearly wants a pathname, + but we forgot to treat it as such by e.g. applying tilde expansion. + + * Consolidate description of tilde-expansion that is done to + configuration variables that take pathname to a single place. + + * Correct faulty recommendation to use "git submodule deinit ." when + de-initialising all submodules, which would result in a strange + error message in a pathological corner case. + + * Many 'linkgit:<git documentation page>' references were broken, + which are all fixed with this. + + * "git rerere" can get confused by conflict markers deliberately left + by the inner merge step, because they are indistinguishable from + the real conflict markers left by the outermost merge which are + what the end user and "rerere" need to look at. This was fixed by + making the conflict markers left by the inner merges a bit longer. + (merge 0f9fd5c jc/ll-merge-internal later to maint). + + * CI test was taught to build documentation pages. + + * "git fsck" learned to catch NUL byte in a commit object as + potential error and warn. + + * Portability enhancement for "rebase -i" to help platforms whose + shell does not like "for i in <empty>" (which is not POSIX-kosher). + + * On Windows, .git and optionally any files whose name starts with a + dot are now marked as hidden, with a core.hideDotFiles knob to + customize this behaviour. + + * Documentation for "git merge --verify-signatures" has been updated + to clarify that the signature of only the commit at the tip is + verified. Also the phrasing used for signature and key validity is + adjusted to align with that used by OpenPGP. + + * A couple of bugs around core.autocrlf have been fixed. + + * Many commands normalize command line arguments from NFD to NFC + variant of UTF-8 on OSX, but commands in the "diff" family did + not, causing "git diff $path" to complain that no such path is + known to Git. They have been taught to do the normalization. + + * "git difftool" learned to handle unmerged paths correctly in + dir-diff mode. + + * The "are we talking with TTY, doing an interactive session?" + detection has been updated to work better for "Git for Windows". + + * We forgot to add "git log --decorate=auto" to documentation when we + added the feature back in v2.1.0 timeframe. + (merge 462cbb4 rj/log-decorate-auto later to maint). + + * "git fast-import --export-marks" would overwrite the existing marks + file even when it makes a dump from its custom die routine. + Prevent it from doing so when we have an import-marks file but + haven't finished reading it. + (merge f4beed6 fc/fast-import-broken-marks-file later to maint). + + * "git rebase -i", after it fails to auto-resolve the conflict, had + an unnecessary call to "git rerere" from its very early days, which + was spotted recently; the call has been removed. + (merge 7063693 js/rebase-i-dedup-call-to-rerere later to maint). + + * Other minor clean-ups and documentation updates + (merge cd82b7a pa/cherry-pick-doc-typo later to maint). + (merge 2bb73ae rs/patch-id-use-skip-prefix later to maint). + (merge aa20cbc rs/apply-name-terminate later to maint). + (merge fe17fc0 jc/t2300-setup later to maint). + (merge e256eec jk/shell-portability later to maint). |