UI, Workflows & Features
+ * "git diff" compares the index and the working tree. For paths
+ added with intent-to-add bit, the command shows the full contents
+ of them as added, but the paths themselves were not marked as new
+ files. They are now shown as new by default.
+
+ "git apply" learned the "--intent-to-add" option so that an
+ otherwise working-tree-only application of a patch will add new
+ paths to the index marked with the "intent-to-add" bit.
+
+ * "git grep" learned the "--column" option that gives not just the
+ line number but the column number of the hit.
+
+ * The "-l" option in "git branch -l" is an unfortunate short-hand for
+ "--create-reflog", but many users, both old and new, somehow expect
+ it to be something else, perhaps "--list". This step warns when "-l"
+ is used as a short-hand for "--create-reflog" and warns about the
+ future repurposing of the it when it is used.
+
+ * The userdiff pattern for .php has been updated.
+
+ * The content-transfer-encoding of the message "git send-email" sends
+ out by default was 8bit, which can cause trouble when there is an
+ overlong line to bust RFC 5322/2822 limit. A new option 'auto' to
+ automatically switch to quoted-printable when there is such a line
+ in the payload has been introduced and is made the default.
+
Performance, Internal Implementation, Development Support etc.
+ * The bulk of "git submodule foreach" has been rewritten in C.
+
+ * The in-core "commit" object had an all-purpose "void *util" field,
+ which was tricky to use especially in library-ish part of the
+ code. All of the existing uses of the field has been migrated to a
+ more dedicated "commit-slab" mechanism and the field is eliminated.
+
+ * A less often used command "git show-index" has been modernized.
+ (merge fb3010c31f jk/show-index later to maint).
+
+ * The conversion to pass "the_repository" and then "a_repository"
+ throughout the object access API continues.
+
+ * Continuing with the idea to programatically enumerate various
+ pieces of data required for command line completion, teach the
+ codebase to report the list of configuration variables
+ subcommands care about to help complete them.
+
+ * Separate "rebase -p" codepath out of "rebase -i" implementation to
+ slim down the latter and make it easier to manage.
+
+ * Make refspec parsing codepath more robust.
+
+ * Some flaky tests have been fixed.
+
+ * Continuing with the idea to programmatically enumerate various
+ pieces of data required for command line completion, the codebase
+ has been taught to enumerate options prefixed with "--no-" to
+ negate them.
+
+ * Build and test procedure for netrc credential helper (in contrib/)
+ has been updated.
+
+ * The conversion to pass "the_repository" and then "a_repository"
+ throughout the object access API continues.
+
+ * Remove unused function definitions and declarations from ewah
+ bitmap subsystem.
+
+ * Code preparation to make "git p4" closer to be usable with Python 3.
+
+ * Tighten the API to make it harder to misuse in-tree .gitmodules
+ file, even though it shares the same syntax with configuration
+ files, to read random configuration items from it.
+
+ * "git fast-import" has been updated to avoid attempting to create
+ delta against a zero-byte-long string, which is pointless.
+
+ * The codebase has been updated to compile cleanly with -pedantic
+ option.
+ (merge 2b647a05d7 bb/pedantic later to maint).
+
+ * The character display width table has been updated to match the
+ latest Unicode standard.
+ (merge 570951eea2 bb/unicode-11-width later to maint).
+
+ * test-lint now looks for broken use of "VAR=VAL shell_func" in test
+ scripts.
+
Fixes since v2.18
-----------------
+
+ * "git remote update" can take both a single remote nickname and a
+ nickname for remote groups, and the completion script (in contrib/)
+ has been taught about it.
+ (merge 9cd4382ad5 ls/complete-remote-update-names later to maint).
+
+ * "git fetch --shallow-since=<cutoff>" that specifies the cut-off
+ point that is newer than the existing history used to end up
+ grabbing the entire history. Such a request now errors out.
+ (merge e34de73c56 nd/reject-empty-shallow-request later to maint).
+
+ * Fix for 2.17-era regression around `core.safecrlf`.
+ (merge 6cb09125be as/safecrlf-quiet-fix later to maint).
+
+ * The recent addition of "partial clone" experimental feature kicked
+ in when it shouldn't, namely, when there is no partial-clone filter
+ defined even if extensions.partialclone is set.
+ (merge cac1137dc4 jh/partial-clone later to maint).
+
+ * "git send-pack --signed" (hence "git push --signed" over the http
+ transport) did not read user ident from the config mechanism to
+ determine whom to sign the push certificate as, which has been
+ corrected.
+ (merge d067d98887 ms/send-pack-honor-config later to maint).
+
+ * "git fetch-pack --all" used to unnecessarily fail upon seeing an
+ annotated tag that points at an object other than a commit.
+ (merge c12c9df527 jk/fetch-all-peeled-fix later to maint).
+
+ * When user edits the patch in "git add -p" and the user's editor is
+ set to strip trailing whitespaces indiscriminately, an empty line
+ that is unchanged in the patch would become completely empty
+ (instead of a line with a sole SP on it). The code introduced in
+ Git 2.17 timeframe failed to parse such a patch, but now it learned
+ to notice the situation and cope with it.
+ (merge f4d35a6b49 pw/add-p-recount later to maint).
+
+ * The code to try seeing if a fetch is necessary in a submodule
+ during a fetch with --recurse-submodules got confused when the path
+ to the submodule was changed in the range of commits in the
+ superproject, sometimes showing "(null)". This has been corrected.
+
+ * "git submodule" did not correctly adjust core.worktree setting that
+ indicates whether/where a submodule repository has its associated
+ working tree across various state transitions, which has been
+ corrected.
+ (merge 984cd77ddb sb/submodule-core-worktree later to maint).
+
+ * Bugfix for "rebase -i" corner case regression.
+ (merge a9279c6785 pw/rebase-i-keep-reword-after-conflict later to maint).
+
+ * Recently added "--base" option to "git format-patch" command did
+ not correctly generate prereq patch ids.
+ (merge 15b76c1fb3 xy/format-patch-prereq-patch-id-fix later to maint).
+
+ * POSIX portability fix in Makefile to fix a glitch introduced a few
+ releases ago.
+ (merge 6600054e9b dj/runtime-prefix later to maint).
+
+ * "git filter-branch" when used with the "--state-branch" option
+ still attempted to rewrite the commits whose filtered result is
+ known from the previous attempt (which is recorded on the state
+ branch); the command has been corrected not to waste cycles doing
+ so.
+ (merge 709cfe848a mb/filter-branch-optim later to maint).
+
+ * Clarify that setting core.ignoreCase to deviate from reality would
+ not turn a case-incapable filesystem into a case-capable one.
+ (merge 48294b512a ms/core-icase-doc later to maint).
+
+ * "fsck.skipList" did not prevent a blob object listed there from
+ being inspected for is contents (e.g. we recently started to
+ inspect the contents of ".gitmodules" for certain malicious
+ patterns), which has been corrected.
+ (merge fb16287719 rj/submodule-fsck-skip later to maint).
+
+ * "git checkout --recurse-submodules another-branch" did not report
+ in which submodule it failed to update the working tree, which
+ resulted in an unhelpful error message.
+ (merge ba95d4e4bd sb/submodule-move-head-error-msg later to maint).
+
+ * "git rebase" behaved slightly differently depending on which one of
+ the three backends gets used; this has been documented and an
+ effort to make them more uniform has begun.
+ (merge b00bf1c9a8 en/rebase-consistency later to maint).
+
+ * The "--ignore-case" option of "git for-each-ref" (and its friends)
+ did not work correctly, which has been fixed.
+ (merge e674eb2528 jk/for-each-ref-icase later to maint).
+
+ * "git fetch" failed to correctly validate the set of objects it
+ received when making a shallow history deeper, which has been
+ corrected.
+ (merge cf1e7c0770 jt/connectivity-check-after-unshallow later to maint).
+
+ * Partial clone support of "git clone" has been updated to correctly
+ validate the objects it receives from the other side. The server
+ side has been corrected to send objects that are directly
+ requested, even if they may match the filtering criteria (e.g. when
+ doing a "lazy blob" partial clone).
+ (merge a7e67c11b8 jt/partial-clone-fsck-connectivity later to maint).
+
+ * Handling of an empty range by "git cherry-pick" was inconsistent
+ depending on how the range ended up to be empty, which has been
+ corrected.
+ (merge c5e358d073 jk/empty-pick-fix later to maint).
+
+ * "git reset --merge" (hence "git merge ---abort") and "git reset --hard"
+ had trouble working correctly in a sparsely checked out working
+ tree after a conflict, which has been corrected.
+ (merge b33fdfc34c mk/merge-in-sparse-checkout later to maint).
+
+ * Correct a broken use of "VAR=VAL shell_func" in a test.
+ (merge 650161a277 jc/t3404-one-shot-export-fix later to maint).
+
+ * "git rev-parse ':/substring'" did not consider the history leading
+ only to HEAD when looking for a commit with the given substring,
+ when the HEAD is detached. This has been fixed.
+ (merge 6b3351e799 wc/find-commit-with-pattern-on-detached-head later to maint).
+
+ * Build doc update for Windows.
+ (merge ede8d89bb1 nd/command-list later to maint).
+
+ * core.commentchar is now honored when preparing the list of commits
+ to replay in "rebase -i".
+
+ * Code cleanup, docfix, build fix, etc.
+ (merge aee9be2ebe sg/update-ref-stdin-cleanup later to maint).
+ (merge 037714252f jc/clean-after-sanity-tests later to maint).
+ (merge 5b26c3c941 en/merge-recursive-cleanup later to maint).
+ (merge 0dcbc0392e bw/config-refer-to-gitsubmodules-doc later to maint).
+ (merge bb4d000e87 bw/protocol-v2 later to maint).
+ (merge 928f0ab4ba vs/typofixes later to maint).
+ (merge d7f590be84 en/rebase-i-microfixes later to maint).
+ (merge 81d395cc85 js/rebase-recreate-merge later to maint).
+ (merge 51d1863168 tz/exclude-doc-smallfixes later to maint).
+ (merge a9aa3c0927 ds/commit-graph later to maint).
+ (merge 5cf8e06474 js/enhanced-version-info later to maint).
+ (merge 6aaded5509 tb/config-default later to maint).
+ (merge 022d2ac1f3 sb/blame-color later to maint).