[PATCH v2 2/2] submodule--helper: advise on fatal alternate error
When recursively cloning a superproject with some shallow modules defined in its .gitmodules, then recloning with "--reference=<path>", an error occurs. For example:
git clone --recurse-submodules --branch=master -j8 \
https://android.googlesource.com/platform/superproject \
master
git clone --recurse-submodules --branch=master -j8 \
https://android.googlesource.com/platform/superproject \
--reference master master2fails with:
fatal: submodule '<snip>' cannot add alternate: reference repository
'<snip>' is shallow
When a alternate computed from the superproject's alternate cannot be added, whether in this case or another, advise about configuring the "submodule.alternateErrorStrategy" configuration option and using "--reference-if-able" instead of "--reference" when cloning.
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
---
Documentation/config/advice.txt | 3 +++
advice.c | 2 ++
advice.h | 1 +
builtin/submodule--helper.c | 10 ++++++++++
4 files changed, 16 insertions(+)
Show changes to 4 files +16 −0
Documentation/config/advice.txt, advice.c, advice.h, builtin/submodule--helper.c
diff --git a/Documentation/config/advice.txt b/Documentation/config/advice.txt
index 6aaa360202..d4e698cd3f 100644
--- a/Documentation/config/advice.txt
+++ b/Documentation/config/advice.txt
@@ -107,4 +107,7 @@ advice.*::
editor input from the user.
nestedTag::
Advice shown if a user attempts to recursively tag a tag object.
+ submoduleAlternateErrorStrategyDie:
+ Advice shown when a submodule.alternateErrorStrategy option
+ configured to "die" causes a fatal error.
--
diff --git a/advice.c b/advice.c
index 3ee0ee2d8f..249c60dcf3 100644
--- a/advice.c
+++ b/advice.c
@@ -30,6 +30,7 @@ int advice_waiting_for_editor = 1;
int advice_graft_file_deprecated = 1;
int advice_checkout_ambiguous_remote_branch_name = 1;
int advice_nested_tag = 1;
+int advice_submodule_alternate_error_strategy_die = 1;
static int advice_use_color = -1;
static char advice_colors[][COLOR_MAXLEN] = {
@@ -89,6 +90,7 @@ static struct {
{ "graftFileDeprecated", &advice_graft_file_deprecated },
{ "checkoutAmbiguousRemoteBranchName", &advice_checkout_ambiguous_remote_branch_name },
{ "nestedTag", &advice_nested_tag },
+ { "submoduleAlternateErrorStrategyDie", &advice_submodule_alternate_error_strategy_die },
/* make this an alias for backward compatibility */
{ "pushNonFastForward", &advice_push_update_rejected }
diff --git a/advice.h b/advice.h
index d015404843..b706780614 100644
--- a/advice.h
+++ b/advice.h
@@ -30,6 +30,7 @@ extern int advice_waiting_for_editor;
extern int advice_graft_file_deprecated;
extern int advice_checkout_ambiguous_remote_branch_name;
extern int advice_nested_tag;
+extern int advice_submodule_alternate_error_strategy_die;
int git_default_advice_config(const char *var, const char *value);
__attribute__((format (printf, 1, 2)))
diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 2c2395a620..12d546dfbb 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -19,6 +19,7 @@
#include "diffcore.h"
#include "diff.h"
#include "object-store.h"
+#include "advice.h"
#define OPT_QUIET (1 << 0)
#define OPT_CACHED (1 << 1)
@@ -1268,6 +1269,13 @@ struct submodule_alternate_setup {
#define SUBMODULE_ALTERNATE_SETUP_INIT { NULL, \
SUBMODULE_ALTERNATE_ERROR_IGNORE, NULL }
+static const char alternate_error_advice[] = N_(
+"An alternate computed from a superproject's alternate is invalid.\n"
+"To allow Git to clone without an alternate in such a case, set\n"
+"submodule.alternateErrorStrategy to 'info' or, equivalently, clone with\n"
+"'--reference-if-able' instead of '--reference'."
+);
+
static int add_possible_reference_from_superproject(
struct object_directory *odb, void *sas_cb)
{
@@ -1299,6 +1307,8 @@ static int add_possible_reference_from_superproject(
} else {
switch (sas->error_mode) {
case SUBMODULE_ALTERNATE_ERROR_DIE:
+ if (advice_submodule_alternate_error_strategy_die)
+ advise(_(alternate_error_advice));
die(_("submodule '%s' cannot add alternate: %s"),
sas->submodule_name, err.buf);
case SUBMODULE_ALTERNATE_ERROR_INFO:
--
2.24.0.393.g34dc348eaf-goog
