Merge branch 'ps/history' into pw/replay-drop-empty

* ps/history: (185 commits)
  builtin/history: implement "reword" subcommand
  builtin: add new "history" command
  wt-status: provide function to expose status for trees
  replay: yield the object ID of the final rewritten commit
  replay: small set of cleanups
  builtin/replay: move core logic into "libgit.a"
  builtin/replay: extract core logic to replay revisions
  The 15th batch
  t3650: add more regression tests for failure conditions
  replay: die if we cannot parse object
  replay: improve code comment and die message
  replay: die descriptively when invalid commit-ish is given
  replay: find *onto only after testing for ref name
  replay: remove dead code and rearrange
  The 14th batch
  The 13th batch
  config: use git_parse_int() in git_config_get_expiry_in_days()
  receive-pack: convert receive hooks to hook API
  receive-pack: convert update hooks to new API
  hooks: allow callers to capture output
  ...

Author: gitster

.github/workflows/main.yml

@@ -443,7 +443,7 @@ jobs:
     - run: ci/install-dependencies.sh
     - run: useradd builder --create-home
     - run: chown -R builder .
-    - run: sudo --preserve-env --set-home --user=builder ci/run-build-and-tests.sh
+    - run: chmod a+w $GITHUB_ENV && sudo --preserve-env --set-home --user=builder ci/run-build-and-tests.sh
     - name: print test failures
       if: failure() && env.FAILED_TEST_ARTIFACTS != ''
       run: sudo --preserve-env --set-home --user=builder ci/print-test-failures.sh

.gitignore

@@ -79,6 +79,7 @@
 /git-grep
 /git-hash-object
 /git-help
+/git-history
 /git-hook
 /git-http-backend
 /git-http-fetch

Documentation/Makefile

@@ -143,6 +143,7 @@ TECH_DOCS += technical/shallow
 TECH_DOCS += technical/sparse-checkout
 TECH_DOCS += technical/sparse-index
 TECH_DOCS += technical/trivial-merge
+TECH_DOCS += technical/unambiguous-types
 TECH_DOCS += technical/unit-tests
 SP_ARTICLES += $(TECH_DOCS)
 SP_ARTICLES += technical/api-index

Documentation/RelNotes/2.53.0.adoc

@@ -20,6 +20,20 @@ UI, Workflows & Features
 
  * Add a new manual that describes the data model.
 
+ * "git fast-import" learns "--strip-if-invalid" option to drop
+   invalid cryptographic signature from objects.
+
+ * The use of "revision" (a connected set of commits) has been
+   clarified in the "git replay" documentation.
+
+ * A help message from "git branch" now mentions "git help" instead of
+   "man" when suggesting to read some documentation.
+
+ * "git repo struct" learned to take "-z" as a synonym to "--format=nul".
+
+ * More object database related information are shown in "git repo
+   structure" output.
+
 
 Performance, Internal Implementation, Development Support etc.
 --------------------------------------------------------------
@@ -38,6 +52,46 @@ Performance, Internal Implementation, Development Support etc.
  * A part of code paths that deals with loose objects has been cleaned
    up.
 
+ * "make strip" has been taught to strip "scalar" as well as "git".
+
+ * Dockerised jobs at the GitHub Actions CI have been taught to show
+   more details of failed tests.
+
+ * Code refactoring around object database sources.
+
+ * Halve the memory consumed by artificial filepairs created during
+   "git diff --find-copioes-harder", also making the operation run
+   faster.
+
+ * The "git_istream" abstraction has been revamped to make it easier
+   to interface with pluggable object database design.
+
+ * Rewrite the only use of "mktemp()" that is subject to TOCTOU race
+   and Stop using the insecure "mktemp()" function.
+   (merge 10bba537c4 rs/ban-mktemp later to maint).
+
+ * In-code comment update to clarify that single-letter options are
+   outside of the scope of command line completion script.
+   (merge dc8a00fafe jc/completion-no-single-letter-options later to maint).
+
+ * MEMZERO_ARRAY() helper is introduced to avoid clearing only the
+   first N bytes of an N-element array whose elements are larger than
+   a byte.
+
+ * "git diff-files -R --find-copies-harder" has been taught to use
+   the potential copy sources from the index correctly.
+
+ * Require C99 style flexible array member support from all platforms.
+
+ * The code path that enumerates promisor objects have been optimized
+   to skip pointlessly parsing blob objects.
+
+ * Prepare test suite for Git for Windows that supports symbolic
+   links.
+
+ * Use hook API to replace ad-hoc invocation of hook scripts with the
+   run_command() API.
+
 
 Fixes since v2.52
 -----------------
@@ -105,8 +159,96 @@ Fixes since v2.52
  * Various issues detected by Asan have been corrected.
    (merge a031b6181a jk/asan-bonanza later to maint).
 
+ * "git config get --path" segfaulted on an ":(optional)path" that
+   does not exist, which has been corrected.
+   (merge 0bd16856ff jc/optional-path later to maint).
+
+ * The "--committer-date-is-author-date" option of "git am/rebase" is
+   a misguided one.  The documentation is updated to discourage its
+   use.
+   (merge fbf3d0669f kh/doc-committer-date-is-author-date later to maint).
+
+ * The option help text given by "git config unset -h" described
+   the "--all" option to "replace", not "unset", multiple variables,
+   which has been corrected.
+   (merge 18bf67b753 rs/config-unset-opthelp-fix later to maint).
+
+ * The error message given by "git config set", when the variable
+   being updated has more than one values defined, used old style "git
+   config" syntax with an incorrect option in its hint, both of which
+   have been corrected.
+   (merge df963f0df4 rs/config-set-multi-error-message-fix later to maint).
+
+ * "git replay" forgot to omit the "gpgsig-sha256" extended header
+   from the resulting commit the same way it omits "gpgsig", which has
+   been corrected.
+   (merge 9f3a115087 pw/replay-exclude-gpgsig-fix later to maint).
+
+ * A few tests have been updated to work under the shell compatible
+   mode of zsh.
+   (merge a92f243a94 bc/zsh-testsuite later to maint).
+
+ * The way patience diff finds LCS has been optimized.
+   (merge c7e3b8085b yc/xdiff-patience-optim later to maint).
+
+ * Recent optimization to "last-modified" command introduced use of
+   uninitialized block of memory, which has been corrected.
+   (merge fe4e60759b tc/last-modified-active-paths-optimization later to maint).
+
+ * "git last-modified" used to mishandle "--" to mark the beginning of
+   pathspec, which has been corrected.
+   (merge 05491b90ce js/last-modified-with-sparse-checkouts later to maint).
+
+ * Emulation code clean-up.
+   (merge 42aa7603aa gf/win32-pthread-cond-init later to maint).
+
+ * "git submodule add" to add a submodule under <name> segfaulted,
+   when a submodule.<name>.something is already in .gitmodules file
+   without defining where its submodule.<name>.path is, which has been
+   corrected.
+   (merge dd8e8c786e jc/submodule-add later to maint).
+
+ * "git fetch" that involves fetching tags, when a tag being fetched
+   needs to overwrite existing one, failed to fetch other tags, which
+   has been corrected.
+   (merge b7b17ec8a6 kn/fix-fetch-backfill-tag-with-batched-ref-updates later to maint).
+
+ * Document "rev-list --filter-provided-objects" better.
+   (merge 6d8dc99478 jt/doc-rev-list-filter-provided-objects later to maint).
+
+ * Even when there is no changes in the packfile and no need to
+   recompute bitmaps, "git repack" recomputed and updated the MIDX
+   file, which has been corrected.
+   (merge 6ce9d558ce ps/repack-avoid-noop-midx-rewrite later to maint).
+
+ * Update HTTP tests to adjust for changes in curl 8.18.0
+   (merge 17f4b01da7 jk/test-curl-updates later to maint).
+
+ * Workaround the "iconv" shipped as part of macOS, which is broken
+   handling stateful ISO/IEC 2022 encoded strings.
+   (merge cee341e9dd rs/macos-iconv-workaround later to maint).
+
  * Other code cleanup, docfix, build fix, etc.
    (merge 46207a54cc qj/doc-http-bad-want-response later to maint).
    (merge df90eccd93 kh/doc-commit-extra-references later to maint).
    (merge f18aa68861 rs/xmkstemp-simplify later to maint).
    (merge fddba8f737 ja/doc-synopsis-style later to maint).
+   (merge 22ce0cb639 en/xdiff-cleanup-2 later to maint).
+   (merge 8ef7355a8f je/doc-pull later to maint).
+   (merge 48176f953f jc/capability-leak later to maint).
+   (merge 8cbbdc92f7 kh/doc-pre-commit-fix later to maint).
+   (merge d4bc39a4d9 mh/doc-config-gui-gcwarning later to maint).
+   (merge 41d425008a kh/doc-send-email-paragraph-fix later to maint).
+   (merge d4b732899e jc/macports-darwinports later to maint).
+   (merge bab391761d kj/pull-options-decl-cleanup later to maint).
+   (merge 007b8994d4 rs/t4014-git-version-string-fix later to maint).
+   (merge 4ce170c522 ds/doc-scalar-config later to maint).
+   (merge a0c813951a jc/doc-commit-signoff-config later to maint).
+   (merge 8ee262985a ja/doc-misc-fixes later to maint).
+   (merge 1722c2244b mh/doc-core-attributesfile later to maint).
+   (merge c469ca26c5 dk/ci-rust-fix later to maint).
+   (merge 12f0be0857 gf/clear-path-cache-cleanup later to maint).
+   (merge 949df6ed6b js/test-func-comment-fix later to maint).
+   (merge 93f894c001 bc/checkout-error-message-fix later to maint).
+   (merge abf05d856f rs/show-branch-prio-queue later to maint).
+   (merge 06188ea5f3 rs/parse-config-expiry-simplify later to maint).

Documentation/config/core.adoc

@@ -492,10 +492,9 @@ core.askPass::
 	command-line argument and write the password on its STDOUT.
 
 core.attributesFile::
-	In addition to `.gitattributes` (per-directory) and
-	`.git/info/attributes`, Git looks into this file for attributes
-	(see linkgit:gitattributes[5]). Path expansions are made the same
-	way as for `core.excludesFile`. Its default value is
+	Specifies the pathname to the file that contains attributes (see
+	linkgit:gitattributes[5]), in addition to `.gitattributes` (per-directory)
+	and `.git/info/attributes`. Its default value is
 	`$XDG_CONFIG_HOME/git/attributes`. If `$XDG_CONFIG_HOME` is either not
 	set or empty, `$HOME/.config/git/attributes` is used instead.
 

Documentation/config/gui.adoc

@@ -55,3 +55,8 @@ gui.blamehistoryctx::
 	linkgit:gitk[1] for the selected commit, when the `Show History
 	Context` menu item is invoked from 'git gui blame'. If this
 	variable is set to zero, the whole history is shown.
+
+gui.GCWarning::
+	Determines whether linkgit:git-gui[1] should prompt for garbage
+	collection when git detects a large number of loose objects in
+	the repository. The default value is "true".

Documentation/git-am.adoc

@@ -162,6 +162,13 @@ Valid <action> for the `--whitespace` option are:
 	commit creation as the committer date. This allows the
 	user to lie about the committer date by using the same
 	value as the author date.
++
+WARNING: The history walking machinery assumes that commits have
+non-decreasing commit timestamps. You should consider if you really need
+to use this option. Then you should only use this option to override the
+committer date when applying commits on top of a base which commit is
+older (in terms of the commit date) than the oldest patch you are
+applying.
 
 --ignore-date::
 	By default the command records the date from the e-mail

Documentation/git-checkout.adoc

@@ -509,7 +509,7 @@ ARGUMENT DISAMBIGUATION
 -----------------------
 
 When you run `git checkout <something>`, Git tries to guess whether
-`<something>` is intended to be a branch, a commit, or a set of file(s),
+_<something>_ is intended to be a branch, a commit, or a set of file(s),
 and then either switches to that branch or commit, or restores the
 specified files.
 

Documentation/git-fast-import.adoc

@@ -66,15 +66,26 @@ fast-import stream! This option is enabled automatically for
 remote-helpers that use the `import` capability, as they are
 already trusted to run their own code.
 
---signed-tags=(verbatim|warn-verbatim|warn-strip|strip|abort)::
-	Specify how to handle signed tags.  Behaves in the same way
-	as the same option in linkgit:git-fast-export[1], except that
-	default is 'verbatim' (instead of 'abort').
-
---signed-commits=(verbatim|warn-verbatim|warn-strip|strip|abort)::
-	Specify how to handle signed commits.  Behaves in the same way
-	as the same option in linkgit:git-fast-export[1], except that
-	default is 'verbatim' (instead of 'abort').
+`--signed-tags=(verbatim|warn-verbatim|warn-strip|strip|abort)`::
+	Specify how to handle signed tags. Behaves in the same way as
+	the `--signed-commits=<mode>` below, except that the
+	`strip-if-invalid` mode is not yet supported. Like for signed
+	commits, the default mode is `verbatim`.
+
+`--signed-commits=<mode>`::
+	Specify how to handle signed commits. The following <mode>s
+	are supported:
++
+* `verbatim`, which is the default, will silently import commit
+  signatures.
+* `warn-verbatim` will import them, but will display a warning.
+* `abort` will make this program die when encountering a signed
+  commit.
+* `strip` will silently make the commits unsigned.
+* `warn-strip` will make them unsigned, but will display a warning.
+* `strip-if-invalid` will check signatures and, if they are invalid,
+  will strip them and display a warning. The validation is performed
+  in the same way as linkgit:git-verify-commit[1] does it.
 
 Options for Frontends
 ~~~~~~~~~~~~~~~~~~~~~

Documentation/git-history.adoc

@@ -0,0 +1,73 @@
+git-history(1)
+==============
+
+NAME
+----
+git-history - EXPERIMENTAL: Rewrite history
+
+SYNOPSIS
+--------
+[synopsis]
+git history reword <commit> [--ref-action=(branches|head|print)]
+
+DESCRIPTION
+-----------
+
+Rewrite history by rearranging or modifying specific commits in the
+history.
+
+THIS COMMAND IS EXPERIMENTAL. THE BEHAVIOR MAY CHANGE.
+
+This command is related to linkgit:git-rebase[1] in that both commands can be
+used to rewrite history. There are a couple of major differences though:
+
+* linkgit:git-history[1] can work in a bare repository as it does not need to
+  touch either the index or the worktree.
+* linkgit:git-history[1] does not execute any linkgit:githooks[5] at the
+  current point in time. This may change in the future.
+* linkgit:git-history[1] by default updates all branches that are descendants
+  of the original commit to point to the rewritten commit.
+
+Overall, linkgit:git-history[1] aims to provide a more opinionated way to modify
+your commit history that is simpler to use compared to linkgit:git-rebase[1] in
+general.
+
+Use linkgit:git-rebase[1] if you want to reapply a range of commits onto a
+different base, or interactive rebases if you want to edit a range of commits
+at once.
+
+LIMITATIONS
+-----------
+
+This command does not (yet) work with histories that contain merges. You
+should use linkgit:git-rebase[1] with the `--rebase-merges` flag instead.
+
+Furthermore, the command does not support operations that can result in merge
+conflicts. This limitation is by design as history rewrites are not intended to
+be stateful operations. The limitation can be lifted once (if) Git learns about
+first-class conflicts.
+
+COMMANDS
+--------
+
+Several commands are available to rewrite history in different ways:
+
+`reword <commit>`::
+	Rewrite the commit message of the specified commit. All the other
+	details of this commit remain unchanged. This command will spawn an
+	editor with the current message of that commit.
+
+OPTIONS
+-------
+
+`--ref-action=(branches|head|print)`::
+	Control which references will be updated by the command, if any. With
+	`branches`, all local branches that point to commits which are
+	decendants of the original commit will be rewritten. With `head`, only
+	the current `HEAD` reference will be rewritten. With `print`, all
+	updates as they would be performed with `branches` are printed in a
+	format that can be consumed by linkgit:git-update-ref[1].
+
+GIT
+---
+Part of the linkgit:git[1] suite