Backward Compatibility Notes
----------------------------
+ * Historically, the "-m" (mainline) option can only be used for "git
+ cherry-pick" and "git revert" when working with a merge commit.
+ This version of Git no longer warns or errors out when working with
+ a single-parent commit, as long as the argument to the "-m" option
+ is 1 (i.e. it has only one parent, and the request is to pick or
+ revert relative to that first parent). Scripts that relied on the
+ behaviour may get broken with this change.
+
Updates since v2.20
-------------------
UI, Workflows & Features
* The "http.version" configuration variable can be used with recent
- enough cURL library to force the version of HTTP used to talk when
- fetching and pushing.
+ enough versions of cURL library to force the version of HTTP used
+ to talk when fetching and pushing.
* Small fixes and features for fast-export and fast-import, mostly on
- the fast-export side.
+ the fast-export side has been made.
* "git push $there $src:$dst" rejects when $dst is not a fully
- qualified refname and not clear what the end user meant. The
+ qualified refname and it is not clear what the end user meant. The
codepath has been taught to give a clearer error message, and also
guess where the push should go by taking the type of the pushed
object into account (e.g. a tag object would want to go under
* "git checkout [<tree-ish>] path..." learned to report the number of
paths that have been checked out of the index or the tree-ish,
which gives it the same degree of noisy-ness as the case in which
- the command checks out a branch.
+ the command checks out a branch. "git checkout -m <pathspec>" to
+ undo conflict resolution gives a similar message.
* "git quiltimport" learned "--keep-non-patch" option.
* Custom userformat "log --format" learned %S atom that stands for
the tip the traversal reached the commit from, i.e. --source.
+ * "git instaweb" learned to drive http.server that comes with
+ "batteries included" Python installation (both Python2 & 3).
+
+ * A new encoding UTF-16LE-BOM has been invented to force encoding to
+ UTF-16 with BOM in little endian byte order, which cannot be directly
+ generated by using iconv.
+
+ * A new date format "--date=human" that morphs its output depending
+ on how far the time is from the current time has been introduced.
+ "--date=auto:human" can be used to use this new format (or any
+ existing format) when the output is going to the pager or to the
+ terminal, and otherwise the default format.
+
Performance, Internal Implementation, Development Support etc.
* Code clean-up with optimization for the codepath that checks
(non-)existence of loose objects.
- * More codepaths become aware of working with in-core repository
- instance other than the default "the_repository".
+ * More codepaths have become aware of working with in-core repository
+ instances other than the default "the_repository".
* The "strncat()" function is now among the banned functions.
* Flaky tests can now be repeatedly run under load with the
"--stress" option.
- (merge fb7d1e3ac8 sg/stress-test later to maint).
* Documentation/Makefile is getting prepared for manpage
localization.
* The code to walk tree objects has been taught that we may be
working with object names that are not computed with SHA-1.
+ * The in-core repository instances are passed through more codepaths.
+
+ * Update the protocol message specification to allow only the limited
+ use of scaled quantities. This is to ensure potential compatibility
+ issues will not get out of hand.
+
+ * Micro-optimize the code that prepares commit objects to be walked
+ by "git rev-list" when the commit-graph is available.
+
+ * "git fetch" and "git upload-pack" learned to send all exchanges over
+ the sideband channel while talking the v2 protocol.
+
+ * The codepath to write out commit-graph has been optimized by
+ following the usual pattern of visiting objects in in-pack order.
+
+ * The codepath to show progress meter while writing out commit-graph
+ file has been improved.
+
+ * Cocci rules have been updated to encourage use of strbuf_addbuf().
+
+ * "git rebase --merge" has been reimplemented by reusing the internal
+ machinery used for "git rebase -i".
+
+ * More code in "git bisect" has been rewritten in C.
+
+ * Instead of going through "git-rebase--am" scriptlet to use the "am"
+ backend, the built-in version of "git rebase" learned to drive the
+ "am" backend directly.
+
+ * The assumption to work on the single "in-core index" instance has
+ been reduced from the library-ish part of the codebase.
+
+ * The test lint learned to catch non-portable "sed" options.
+
+ * "git pack-objects" learned another algorithm to compute the set of
+ objects to send, that trades the resulting packfile off to save
+ traversal cost to favor small pushes.
+
+ * The travis CI scripts have been corrected to build Git with the
+ compiler(s) of our choice.
+
+ * "git submodule update" learned to abort early when core.worktree
+ for the submodule is not set correctly to prevent spreading damage.
+
+ * Test suite has been adjusted to run on Azure Pipeline.
+
+ * Running "Documentation/doc-diff x" from anywhere other than the
+ top-level of the working tree did not show the usage string
+ correctly, which has been fixed.
+
+ * Use of the sparse tool got easier to customize from the command
+ line to help developers.
+
+ * A new target "coverage-prove" to run the coverage test under
+ "prove" has been added.
+
+ * A flakey "p4" test has been removed.
+
+ * The code and tests assume that the system supplied iconv() would
+ always use BOM in its output when asked to encode to UTF-16 (or
+ UTF-32), but apparently some implementations output big-endian
+ without BOM. A compile-time knob has been added to help such
+ systems (e.g. NonStop) to add BOM to the output to increase
+ portability.
+
Fixes since v2.20
-----------------
temporary file.
(merge fa6f225e01 js/add-e-clear-patch-before-stating later to maint).
+ * "git p4" failed to update a shelved change when there were moved
+ files, which has been corrected.
+ (merge 7a10946ab9 ld/git-p4-shelve-update-fix later to maint).
+
+ * The codepath to read from the commit-graph file attempted to read
+ past the end of it when the file's table-of-contents was corrupt.
+
+ * The compat/obstack code had casts that -Wcast-function-type
+ compilation option found questionable.
+ (merge 764473d257 sg/obstack-cast-function-type-fix later to maint).
+
+ * An obvious typo in an assertion error message has been fixed.
+ (merge 3c27e2e059 cc/test-ref-store-typofix later to maint).
+
+ * In Git for Windows, "git clone \\server\share\path" etc. that uses
+ UNC paths from command line had bad interaction with its shell
+ emulation.
+
+ * "git add --ignore-errors" did not work as advertised and instead
+ worked as an unintended synonym for "git add --renormalize", which
+ has been fixed.
+ (merge e2c2a37545 jk/add-ignore-errors-bit-assignment-fix later to maint).
+
+ * On a case-insensitive filesystem, we failed to compare the part of
+ the path that is above the worktree directory in an absolute
+ pathname, which has been corrected.
+
+ * Asking "git check-attr" about a macro (e.g. "binary") on a specific
+ path did not work correctly, even though "git check-attr -a" listed
+ such a macro correctly. This has been corrected.
+ (merge 7b95849be4 jk/attr-macro-fix later to maint).
+
+ * "git pack-objects" incorrectly used uninitialized mutex, which has
+ been corrected.
+ (merge edb673cf10 ph/pack-objects-mutex-fix later to maint).
+
+ * "git checkout -b <new> [HEAD]" to create a new branch from the
+ current commit and check it out ought to be a no-op in the index
+ and the working tree in normal cases, but there are corner cases
+ that do require updates to the index and the working tree. Running
+ it immediately after "git clone --no-checkout" is one of these
+ cases that an earlier optimization kicked in incorrectly, which has
+ been fixed.
+ (merge 8424bfd45b bp/checkout-new-branch-optim later to maint).
+
+ * "git diff --color-moved --cc --stat -p" did not work well due to
+ funny interaction between a bug in color-moved and the rest, which
+ has been fixed.
+ (merge dac03b5518 jk/diff-cc-stat-fixes later to maint).
+
+ * When GIT_SEQUENCE_EDITOR is set, the command was incorrectly
+ started when modes of "git rebase" that implicitly uses the
+ machinery for the interactive rebase are run, which has been
+ corrected.
+ (merge 891d4a0313 pw/no-editor-in-rebase-i-implicit later to maint).
+
+ * The commit-graph facility did not work when in-core objects that
+ are promoted from unknown type to commit (e.g. a commit that is
+ accessed via a tag that refers to it) were involved, which has been
+ corrected.
+ (merge 4468d4435c sg/object-as-type-commit-graph-fix later to maint).
+
+ * "git fetch" output cleanup.
+ (merge dc40b24df4 nd/fetch-compact-update later to maint).
+
+ * "git cat-file --batch" reported a dangling symbolic link by
+ mistake, when it wanted to report that a given name is ambiguous.
+
+ * Documentation around core.crlf has been updated.
+ (merge c9446f0504 jk/autocrlf-overrides-eol-doc later to maint).
+
+ * The documentation of "git commit-tree" said that the command
+ understands "--gpg-sign" in addition to "-S", but the command line
+ parser did not know about the longhand, which has been corrected.
+
+ * "git rebase -x $cmd" did not reject multi-line command, even though
+ the command is incapable of handling such a command. It now is
+ rejected upfront.
+ (merge c762aada1a pw/rebase-x-sanity-check later to maint).
+
+ * Output from "git help" was not correctly aligned, which has been
+ fixed.
+ (merge 6195a76da4 nd/help-align-command-desc later to maint).
+
+ * The "git submodule summary" subcommand showed shortened commit
+ object names by mechanically truncating them at 7-hexdigit, which
+ has been improved to let "rev-parse --short" scale the length of
+ the abbreviation with the size of the repository.
+ (merge 0586a438f6 sh/submodule-summary-abbrev-fix later to maint).
+
+ * The way the OSX build jobs updates its build environment used the
+ "--quiet" option to "brew update" command, but it wasn't all that
+ quiet to be useful. The use of the option has been replaced with
+ an explicit redirection to the /dev/null (which incidentally would
+ have worked around a breakage by recent updates to homebrew, which
+ has fixed itself already).
+ (merge a1ccaedd62 sg/travis-osx-brew-breakage-workaround later to maint).
+
+ * "git --work-tree=$there --git-dir=$here describe --dirty" did not
+ work correctly as it did not pay attention to the location of the
+ worktree specified by the user by mistake, which has been
+ corrected.
+ (merge c801170b0c ss/describe-dirty-in-the-right-directory later to maint).
+
+ * "git fetch" over protocol v2 that needs to make a second connection
+ to backfill tags did not clear a variable that holds shallow
+ repository information correctly, leading to an access of freed
+ piece of memory.
+
+ * Some errors from the other side coming over smart HTTP transport
+ were not noticed, which has been corrected.
+
* Code cleanup, docfix, build fix, etc.
(merge 89ba9a79ae hb/t0061-dot-in-path-fix later to maint).
(merge d173e799ea sb/diff-color-moved-config-option-fixup later to maint).
(merge 0650614982 cy/completion-typofix later to maint).
(merge 6881925ef5 rs/sha1-file-close-mapped-file-on-error later to maint).
(merge bd8d6f0def en/show-ref-doc-fix later to maint).
- (merge 1747125e2c cc/parial-clone-doc-typofix later to maint).
+ (merge 1747125e2c cc/partial-clone-doc-typofix later to maint).
(merge e01378753d cc/fetch-error-message-fix later to maint).
(merge 54e8c11215 jk/remote-insteadof-cleanup later to maint).
+ (merge d609615f48 js/test-git-installed later to maint).
+ (merge ba170517be ja/doc-style-fix later to maint).
+ (merge 86fb1c4e77 km/init-doc-typofix later to maint).
+ (merge 5cfd4a9d10 nd/commit-doc later to maint).
+ (merge 9fce19a431 ab/diff-tree-doc-fix later to maint).
+ (merge 2e285e7803 tz/gpg-test-fix later to maint).
+ (merge 5427de960b kl/pretty-doc-markup-fix later to maint).
+ (merge 3815f64b0d js/mingw-host-cpu later to maint).
+ (merge 5fe81438b5 rj/sequencer-sign-off-header-static later to maint).
+ (merge 18a4f6be6b nd/fileno-may-be-macro later to maint).
+ (merge 99e9ab54ab kd/t0028-octal-del-is-377-not-777 later to maint).