merge(3p/git): Merge git subtree at v2.29.2 r/1890

This also bumps the stable nixpkgs to 20.09 as of 2020-11-21, because
there is some breakage in the git build related to the netrc
credentials helper which someone has taken care of in nixpkgs.

The stable channel is not used for anything other than git, so this
should be fine.

Change-Id: I3575a19dab09e1e9556cf8231d717de9890484fb

1 files changed, 147 insertions, 112 deletions

diff --git a/third_party/git/builtin/pull.c b/third_party/git/builtin/pull.c
index f1eaf6e6edb1..425950f46973 100644
--- a/third_party/git/builtin/pull.c
+++ b/third_party/git/builtin/pull.c
@@ -12,9 +12,10 @@
 #include "parse-options.h"
 #include "exec-cmd.h"
 #include "run-command.h"
-#include "sha1-array.h"
+#include "oid-array.h"
 #include "remote.h"
 #include "dir.h"
+#include "rebase.h"
 #include "refs.h"
 #include "refspec.h"
 #include "revision.h"
@@ -26,15 +27,6 @@
 #include "commit-reach.h"
 #include "sequencer.h"
 
-enum rebase_type {
-	REBASE_INVALID = -1,
-	REBASE_FALSE = 0,
-	REBASE_TRUE,
-	REBASE_PRESERVE,
-	REBASE_MERGES,
-	REBASE_INTERACTIVE
-};
-
 /**
  * Parses the value of --rebase. If value is a false value, returns
  * REBASE_FALSE. If value is a true value, returns REBASE_TRUE. If value is
@@ -45,22 +37,9 @@ enum rebase_type {
 static enum rebase_type parse_config_rebase(const char *key, const char *value,
 		int fatal)
 {
-	int v = git_parse_maybe_bool(value);
-
-	if (!v)
-		return REBASE_FALSE;
-	else if (v > 0)
-		return REBASE_TRUE;
-	else if (!strcmp(value, "preserve") || !strcmp(value, "p"))
-		return REBASE_PRESERVE;
-	else if (!strcmp(value, "merges") || !strcmp(value, "m"))
-		return REBASE_MERGES;
-	else if (!strcmp(value, "interactive") || !strcmp(value, "i"))
-		return REBASE_INTERACTIVE;
-	/*
-	 * Please update _git_config() in git-completion.bash when you
-	 * add new rebase modes.
-	 */
+	enum rebase_type v = rebase_parse_value(value);
+	if (v != REBASE_INVALID)
+		return v;
 
 	if (fatal)
 		die(_("Invalid value for %s: %s"), key, value);
@@ -107,8 +86,9 @@ static char *opt_ff;
 static char *opt_verify_signatures;
 static int opt_autostash = -1;
 static int config_autostash;
-static struct argv_array opt_strategies = ARGV_ARRAY_INIT;
-static struct argv_array opt_strategy_opts = ARGV_ARRAY_INIT;
+static int check_trust_level = 1;
+static struct strvec opt_strategies = STRVEC_INIT;
+static struct strvec opt_strategy_opts = STRVEC_INIT;
 static char *opt_gpg_sign;
 static int opt_allow_unrelated_histories;
 
@@ -129,6 +109,8 @@ static char *opt_refmap;
 static char *opt_ipv4;
 static char *opt_ipv6;
 static int opt_show_forced_updates = -1;
+static char *set_upstream;
+static struct strvec opt_fetch = STRVEC_INIT;
 
 static struct option pull_options[] = {
 	/* Shared options */
@@ -136,17 +118,17 @@ static struct option pull_options[] = {
 	OPT_PASSTHRU(0, "progress", &opt_progress, NULL,
 		N_("force progress reporting"),
 		PARSE_OPT_NOARG),
-	{ OPTION_CALLBACK, 0, "recurse-submodules",
+	OPT_CALLBACK_F(0, "recurse-submodules",
 		   &recurse_submodules, N_("on-demand"),
 		   N_("control for recursive fetching of submodules"),
-		   PARSE_OPT_OPTARG, option_fetch_parse_recurse_submodules },
+		   PARSE_OPT_OPTARG, option_fetch_parse_recurse_submodules),
 
 	/* Options passed to git-merge or git-rebase */
 	OPT_GROUP(N_("Options related to merging")),
-	{ OPTION_CALLBACK, 'r', "rebase", &opt_rebase,
+	OPT_CALLBACK_F('r', "rebase", &opt_rebase,
 	  "(false|true|merges|preserve|interactive)",
 	  N_("incorporate changes by rebasing rather than merging"),
-	  PARSE_OPT_OPTARG, parse_opt_rebase },
+	  PARSE_OPT_OPTARG, parse_opt_rebase),
 	OPT_PASSTHRU('n', NULL, &opt_diffstat, NULL,
 		N_("do not show a diffstat at the end of the merge"),
 		PARSE_OPT_NOARG | PARSE_OPT_NONEG),
@@ -182,7 +164,7 @@ static struct option pull_options[] = {
 		N_("verify that the named commit has a valid GPG signature"),
 		PARSE_OPT_NOARG),
 	OPT_BOOL(0, "autostash", &opt_autostash,
-		N_("automatically stash/stash pop before and after rebase")),
+		N_("automatically stash/stash pop before and after")),
 	OPT_PASSTHRU_ARGV('s', "strategy", &opt_strategies, N_("strategy"),
 		N_("merge strategy to use"),
 		0),
@@ -226,6 +208,15 @@ static struct option pull_options[] = {
 	OPT_PASSTHRU(0, "depth", &opt_depth, N_("depth"),
 		N_("deepen history of shallow clone"),
 		0),
+	OPT_PASSTHRU_ARGV(0, "shallow-since", &opt_fetch, N_("time"),
+		N_("deepen history of shallow repository based on time"),
+		0),
+	OPT_PASSTHRU_ARGV(0, "shallow-exclude", &opt_fetch, N_("revision"),
+		N_("deepen history of shallow clone, excluding rev"),
+		0),
+	OPT_PASSTHRU_ARGV(0, "deepen", &opt_fetch, N_("n"),
+		N_("deepen history of shallow clone"),
+		0),
 	OPT_PASSTHRU(0, "unshallow", &opt_unshallow, NULL,
 		N_("convert to a complete repository"),
 		PARSE_OPT_NONEG | PARSE_OPT_NOARG),
@@ -235,14 +226,24 @@ static struct option pull_options[] = {
 	OPT_PASSTHRU(0, "refmap", &opt_refmap, N_("refmap"),
 		N_("specify fetch refmap"),
 		PARSE_OPT_NONEG),
+	OPT_PASSTHRU_ARGV('o', "server-option", &opt_fetch,
+		N_("server-specific"),
+		N_("option to transmit"),
+		0),
 	OPT_PASSTHRU('4',  "ipv4", &opt_ipv4, NULL,
 		N_("use IPv4 addresses only"),
 		PARSE_OPT_NOARG),
 	OPT_PASSTHRU('6',  "ipv6", &opt_ipv6, NULL,
 		N_("use IPv6 addresses only"),
 		PARSE_OPT_NOARG),
+	OPT_PASSTHRU_ARGV(0, "negotiation-tip", &opt_fetch, N_("revision"),
+		N_("report that we have only objects reachable from this object"),
+		0),
 	OPT_BOOL(0, "show-forced-updates", &opt_show_forced_updates,
 		 N_("check for forced-updates on all updated branches")),
+	OPT_PASSTHRU(0, "set-upstream", &set_upstream, NULL,
+		N_("set upstream for git pull/fetch"),
+		PARSE_OPT_NOARG),
 
 	OPT_END()
 };
@@ -250,25 +251,25 @@ static struct option pull_options[] = {
 /**
  * Pushes "-q" or "-v" switches into arr to match the opt_verbosity level.
  */
-static void argv_push_verbosity(struct argv_array *arr)
+static void argv_push_verbosity(struct strvec *arr)
 {
 	int verbosity;
 
 	for (verbosity = opt_verbosity; verbosity > 0; verbosity--)
-		argv_array_push(arr, "-v");
+		strvec_push(arr, "-v");
 
 	for (verbosity = opt_verbosity; verbosity < 0; verbosity++)
-		argv_array_push(arr, "-q");
+		strvec_push(arr, "-q");
 }
 
 /**
  * Pushes "-f" switches into arr to match the opt_force level.
  */
-static void argv_push_force(struct argv_array *arr)
+static void argv_push_force(struct strvec *arr)
 {
 	int force = opt_force;
 	while (force-- > 0)
-		argv_array_push(arr, "-f");
+		strvec_push(arr, "-f");
 }
 
 /**
@@ -343,6 +344,21 @@ static enum rebase_type config_get_rebase(void)
 	if (!git_config_get_value("pull.rebase", &value))
 		return parse_config_rebase("pull.rebase", value, 1);
 
+	if (opt_verbosity >= 0 && !opt_ff) {
+		warning(_("Pulling without specifying how to reconcile divergent branches is\n"
+			"discouraged. You can squelch this message by running one of the following\n"
+			"commands sometime before your next pull:\n"
+			"\n"
+			"  git config pull.rebase false  # merge (the default strategy)\n"
+			"  git config pull.rebase true   # rebase\n"
+			"  git config pull.ff only       # fast-forward only\n"
+			"\n"
+			"You can replace \"git config\" with \"git config --global\" to set a default\n"
+			"preference for all repositories. You can also pass --rebase, --no-rebase,\n"
+			"or --ff-only on the command line to override the configured default per\n"
+			"invocation.\n"));
+	}
+
 	return REBASE_FALSE;
 }
 
@@ -351,6 +367,8 @@ static enum rebase_type config_get_rebase(void)
  */
 static int git_pull_config(const char *var, const char *value, void *cb)
 {
+	int status;
+
 	if (!strcmp(var, "rebase.autostash")) {
 		config_autostash = git_config_bool(var, value);
 		return 0;
@@ -358,7 +376,14 @@ static int git_pull_config(const char *var, const char *value, void *cb)
 		recurse_submodules = git_config_bool(var, value) ?
 			RECURSE_SUBMODULES_ON : RECURSE_SUBMODULES_OFF;
 		return 0;
+	} else if (!strcmp(var, "gpg.mintrustlevel")) {
+		check_trust_level = 0;
 	}
+
+	status = git_gpg_config(var, value, cb);
+	if (status)
+		return status;
+
 	return git_default_config(var, value, cb);
 }
 
@@ -498,72 +523,75 @@ static void parse_repo_refspecs(int argc, const char **argv, const char **repo,
  */
 static int run_fetch(const char *repo, const char **refspecs)
 {
-	struct argv_array args = ARGV_ARRAY_INIT;
+	struct strvec args = STRVEC_INIT;
 	int ret;
 
-	argv_array_pushl(&args, "fetch", "--update-head-ok", NULL);
+	strvec_pushl(&args, "fetch", "--update-head-ok", NULL);
 
 	/* Shared options */
 	argv_push_verbosity(&args);
 	if (opt_progress)
-		argv_array_push(&args, opt_progress);
+		strvec_push(&args, opt_progress);
 
 	/* Options passed to git-fetch */
 	if (opt_all)
-		argv_array_push(&args, opt_all);
+		strvec_push(&args, opt_all);
 	if (opt_append)
-		argv_array_push(&args, opt_append);
+		strvec_push(&args, opt_append);
 	if (opt_upload_pack)
-		argv_array_push(&args, opt_upload_pack);
+		strvec_push(&args, opt_upload_pack);
 	argv_push_force(&args);
 	if (opt_tags)
-		argv_array_push(&args, opt_tags);
+		strvec_push(&args, opt_tags);
 	if (opt_prune)
-		argv_array_push(&args, opt_prune);
+		strvec_push(&args, opt_prune);
 	if (recurse_submodules != RECURSE_SUBMODULES_DEFAULT)
 		switch (recurse_submodules) {
 		case RECURSE_SUBMODULES_ON:
-			argv_array_push(&args, "--recurse-submodules=on");
+			strvec_push(&args, "--recurse-submodules=on");
 			break;
 		case RECURSE_SUBMODULES_OFF:
-			argv_array_push(&args, "--recurse-submodules=no");
+			strvec_push(&args, "--recurse-submodules=no");
 			break;
 		case RECURSE_SUBMODULES_ON_DEMAND:
-			argv_array_push(&args, "--recurse-submodules=on-demand");
+			strvec_push(&args, "--recurse-submodules=on-demand");
 			break;
 		default:
 			BUG("submodule recursion option not understood");
 		}
 	if (max_children)
-		argv_array_push(&args, max_children);
+		strvec_push(&args, max_children);
 	if (opt_dry_run)
-		argv_array_push(&args, "--dry-run");
+		strvec_push(&args, "--dry-run");
 	if (opt_keep)
-		argv_array_push(&args, opt_keep);
+		strvec_push(&args, opt_keep);
 	if (opt_depth)
-		argv_array_push(&args, opt_depth);
+		strvec_push(&args, opt_depth);
 	if (opt_unshallow)
-		argv_array_push(&args, opt_unshallow);
+		strvec_push(&args, opt_unshallow);
 	if (opt_update_shallow)
-		argv_array_push(&args, opt_update_shallow);
+		strvec_push(&args, opt_update_shallow);
 	if (opt_refmap)
-		argv_array_push(&args, opt_refmap);
+		strvec_push(&args, opt_refmap);
 	if (opt_ipv4)
-		argv_array_push(&args, opt_ipv4);
+		strvec_push(&args, opt_ipv4);
 	if (opt_ipv6)
-		argv_array_push(&args, opt_ipv6);
+		strvec_push(&args, opt_ipv6);
 	if (opt_show_forced_updates > 0)
-		argv_array_push(&args, "--show-forced-updates");
+		strvec_push(&args, "--show-forced-updates");
 	else if (opt_show_forced_updates == 0)
-		argv_array_push(&args, "--no-show-forced-updates");
+		strvec_push(&args, "--no-show-forced-updates");
+	if (set_upstream)
+		strvec_push(&args, set_upstream);
+	strvec_pushv(&args, opt_fetch.v);
 
 	if (repo) {
-		argv_array_push(&args, repo);
-		argv_array_pushv(&args, refspecs);
+		strvec_push(&args, repo);
+		strvec_pushv(&args, refspecs);
 	} else if (*refspecs)
 		BUG("refspecs without repo?");
-	ret = run_command_v_opt(args.argv, RUN_GIT_CMD);
-	argv_array_clear(&args);
+	ret = run_command_v_opt(args.v, RUN_GIT_CMD);
+	strvec_clear(&args);
 	return ret;
 }
 
@@ -581,7 +609,8 @@ static int pull_into_void(const struct object_id *merge_head,
 			die(_("unable to access commit %s"),
 			    oid_to_hex(merge_head));
 
-		verify_merge_signature(commit, opt_verbosity);
+		verify_merge_signature(commit, opt_verbosity,
+				       check_trust_level);
 	}
 
 	/*
@@ -607,8 +636,8 @@ static int rebase_submodules(void)
 
 	cp.git_cmd = 1;
 	cp.no_stdin = 1;
-	argv_array_pushl(&cp.args, "submodule", "update",
-				   "--recursive", "--rebase", NULL);
+	strvec_pushl(&cp.args, "submodule", "update",
+		     "--recursive", "--rebase", NULL);
 	argv_push_verbosity(&cp.args);
 
 	return run_command(&cp);
@@ -620,8 +649,8 @@ static int update_submodules(void)
 
 	cp.git_cmd = 1;
 	cp.no_stdin = 1;
-	argv_array_pushl(&cp.args, "submodule", "update",
-				   "--recursive", "--checkout", NULL);
+	strvec_pushl(&cp.args, "submodule", "update",
+		     "--recursive", "--checkout", NULL);
 	argv_push_verbosity(&cp.args);
 
 	return run_command(&cp);
@@ -633,44 +662,48 @@ static int update_submodules(void)
 static int run_merge(void)
 {
 	int ret;
-	struct argv_array args = ARGV_ARRAY_INIT;
+	struct strvec args = STRVEC_INIT;
 
-	argv_array_pushl(&args, "merge", NULL);
+	strvec_pushl(&args, "merge", NULL);
 
 	/* Shared options */
 	argv_push_verbosity(&args);
 	if (opt_progress)
-		argv_array_push(&args, opt_progress);
+		strvec_push(&args, opt_progress);
 
 	/* Options passed to git-merge */
 	if (opt_diffstat)
-		argv_array_push(&args, opt_diffstat);
+		strvec_push(&args, opt_diffstat);
 	if (opt_log)
-		argv_array_push(&args, opt_log);
+		strvec_push(&args, opt_log);
 	if (opt_signoff)
-		argv_array_push(&args, opt_signoff);
+		strvec_push(&args, opt_signoff);
 	if (opt_squash)
-		argv_array_push(&args, opt_squash);
+		strvec_push(&args, opt_squash);
 	if (opt_commit)
-		argv_array_push(&args, opt_commit);
+		strvec_push(&args, opt_commit);
 	if (opt_edit)
-		argv_array_push(&args, opt_edit);
+		strvec_push(&args, opt_edit);
 	if (cleanup_arg)
-		argv_array_pushf(&args, "--cleanup=%s", cleanup_arg);
+		strvec_pushf(&args, "--cleanup=%s", cleanup_arg);
 	if (opt_ff)
-		argv_array_push(&args, opt_ff);
+		strvec_push(&args, opt_ff);
 	if (opt_verify_signatures)
-		argv_array_push(&args, opt_verify_signatures);
-	argv_array_pushv(&args, opt_strategies.argv);
-	argv_array_pushv(&args, opt_strategy_opts.argv);
+		strvec_push(&args, opt_verify_signatures);
+	strvec_pushv(&args, opt_strategies.v);
+	strvec_pushv(&args, opt_strategy_opts.v);
 	if (opt_gpg_sign)
-		argv_array_push(&args, opt_gpg_sign);
+		strvec_push(&args, opt_gpg_sign);
+	if (opt_autostash == 0)
+		strvec_push(&args, "--no-autostash");
+	else if (opt_autostash == 1)
+		strvec_push(&args, "--autostash");
 	if (opt_allow_unrelated_histories > 0)
-		argv_array_push(&args, "--allow-unrelated-histories");
+		strvec_push(&args, "--allow-unrelated-histories");
 
-	argv_array_push(&args, "FETCH_HEAD");
-	ret = run_command_v_opt(args.argv, RUN_GIT_CMD);
-	argv_array_clear(&args);
+	strvec_push(&args, "FETCH_HEAD");
+	ret = run_command_v_opt(args.v, RUN_GIT_CMD);
+	strvec_clear(&args);
 	return ret;
 }
 
@@ -767,8 +800,8 @@ static int get_rebase_fork_point(struct object_id *fork_point, const char *repo,
 	if (!remote_branch)
 		return -1;
 
-	argv_array_pushl(&cp.args, "merge-base", "--fork-point",
-			remote_branch, curr_branch->name, NULL);
+	strvec_pushl(&cp.args, "merge-base", "--fork-point",
+		     remote_branch, curr_branch->name, NULL);
 	cp.no_stdin = 1;
 	cp.no_stderr = 1;
 	cp.git_cmd = 1;
@@ -828,48 +861,48 @@ static int run_rebase(const struct object_id *curr_head,
 {
 	int ret;
 	struct object_id oct_merge_base;
-	struct argv_array args = ARGV_ARRAY_INIT;
+	struct strvec args = STRVEC_INIT;
 
 	if (!get_octopus_merge_base(&oct_merge_base, curr_head, merge_head, fork_point))
 		if (!is_null_oid(fork_point) && oideq(&oct_merge_base, fork_point))
 			fork_point = NULL;
 
-	argv_array_push(&args, "rebase");
+	strvec_push(&args, "rebase");
 
 	/* Shared options */
 	argv_push_verbosity(&args);
 
 	/* Options passed to git-rebase */
 	if (opt_rebase == REBASE_MERGES)
-		argv_array_push(&args, "--rebase-merges");
+		strvec_push(&args, "--rebase-merges");
 	else if (opt_rebase == REBASE_PRESERVE)
-		argv_array_push(&args, "--preserve-merges");
+		strvec_push(&args, "--preserve-merges");
 	else if (opt_rebase == REBASE_INTERACTIVE)
-		argv_array_push(&args, "--interactive");
+		strvec_push(&args, "--interactive");
 	if (opt_diffstat)
-		argv_array_push(&args, opt_diffstat);
-	argv_array_pushv(&args, opt_strategies.argv);
-	argv_array_pushv(&args, opt_strategy_opts.argv);
+		strvec_push(&args, opt_diffstat);
+	strvec_pushv(&args, opt_strategies.v);
+	strvec_pushv(&args, opt_strategy_opts.v);
 	if (opt_gpg_sign)
-		argv_array_push(&args, opt_gpg_sign);
+		strvec_push(&args, opt_gpg_sign);
 	if (opt_autostash == 0)
-		argv_array_push(&args, "--no-autostash");
+		strvec_push(&args, "--no-autostash");
 	else if (opt_autostash == 1)
-		argv_array_push(&args, "--autostash");
+		strvec_push(&args, "--autostash");
 	if (opt_verify_signatures &&
 	    !strcmp(opt_verify_signatures, "--verify-signatures"))
 		warning(_("ignoring --verify-signatures for rebase"));
 
-	argv_array_push(&args, "--onto");
-	argv_array_push(&args, oid_to_hex(merge_head));
+	strvec_push(&args, "--onto");
+	strvec_push(&args, oid_to_hex(merge_head));
 
 	if (fork_point && !is_null_oid(fork_point))
-		argv_array_push(&args, oid_to_hex(fork_point));
+		strvec_push(&args, oid_to_hex(fork_point));
 	else
-		argv_array_push(&args, oid_to_hex(merge_head));
+		strvec_push(&args, oid_to_hex(merge_head));
 
-	ret = run_command_v_opt(args.argv, RUN_GIT_CMD);
-	argv_array_clear(&args);
+	ret = run_command_v_opt(args.v, RUN_GIT_CMD);
+	strvec_clear(&args);
 	return ret;
 }
 
@@ -912,9 +945,6 @@ int cmd_pull(int argc, const char **argv, const char *prefix)
 	if (get_oid("HEAD", &orig_head))
 		oidclr(&orig_head);
 
-	if (!opt_rebase && opt_autostash != -1)
-		die(_("--[no-]autostash option is only valid with --rebase."));
-
 	autostash = config_autostash;
 	if (opt_rebase) {
 		if (opt_autostash != -1)
@@ -980,6 +1010,7 @@ int cmd_pull(int argc, const char **argv, const char *prefix)
 
 	if (opt_rebase) {
 		int ret = 0;
+		int ran_ff = 0;
 		if ((recurse_submodules == RECURSE_SUBMODULES_ON ||
 		     recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) &&
 		    submodule_touches_in_range(the_repository, &rebase_fork_point, &curr_head))
@@ -993,13 +1024,17 @@ int cmd_pull(int argc, const char **argv, const char *prefix)
 			commit_list_insert(head, &list);
 			merge_head = lookup_commit_reference(the_repository,
 							     &merge_heads.oid[0]);
-			if (is_descendant_of(merge_head, list)) {
+			if (repo_is_descendant_of(the_repository,
+						  merge_head, list)) {
 				/* we can fast-forward this without invoking rebase */
 				opt_ff = "--ff-only";
+				ran_ff = 1;
 				ret = run_merge();
 			}
+			free_commit_list(list);
 		}
-		ret = run_rebase(&curr_head, merge_heads.oid, &rebase_fork_point);
+		if (!ran_ff)
+			ret = run_rebase(&curr_head, merge_heads.oid, &rebase_fork_point);
 
 		if (!ret && (recurse_submodules == RECURSE_SUBMODULES_ON ||
 			     recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND))