advice: update message to suggest '--sparse'

The previous changes modified the behavior of 'git add', 'git rm', and
'git mv' to not adjust paths outside the sparse-checkout cone, even if
they exist in the working tree and their cache entries lack the
SKIP_WORKTREE bit. The intention is to warn users that they are doing
something potentially dangerous. The '--sparse' option was added to each
command to allow careful users the same ability they had before.

To improve the discoverability of this new functionality, add a message
to advice.updateSparsePath that mentions the existence of the option.

The previous set of changes also modified the purpose of this message to
include possibly a list of paths instead of only a list of pathspecs.
Make the warning message more clear about this new behavior.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

advice.c

@@ -293,15 +293,16 @@ void advise_on_updating_sparse_paths(struct string_list *pathspec_list)
 	if (!pathspec_list->nr)
 		return;
 
-	fprintf(stderr, _("The following pathspecs didn't match any"
-			  " eligible path, but they do match index\n"
-			  "entries outside the current sparse checkout:\n"));
+	fprintf(stderr, _("The following paths and/or pathspecs matched paths that exist\n"
+			  "outside of your sparse-checkout definition, so will not be\n"
+			  "updated in the index:\n"));
 	for_each_string_list_item(item, pathspec_list)
 		fprintf(stderr, "%s\n", item->string);
 
 	advise_if_enabled(ADVICE_UPDATE_SPARSE_PATH,
-			  _("Disable or modify the sparsity rules if you intend"
-			    " to update such entries."));
+			  _("If you intend to update such entries, try one of the following:\n"
+			    "* Use the --sparse option.\n"
+			    "* Disable or modify the sparsity rules."));
 }
 
 void detach_advice(const char *new_name)

t/t3602-rm-sparse-checkout.sh

@@ -11,12 +11,15 @@ test_expect_success 'setup' "
 	git commit -m files &&
 
 	cat >sparse_error_header <<-EOF &&
-	The following pathspecs didn't match any eligible path, but they do match index
-	entries outside the current sparse checkout:
+	The following paths and/or pathspecs matched paths that exist
+	outside of your sparse-checkout definition, so will not be
+	updated in the index:
 	EOF
 
 	cat >sparse_hint <<-EOF &&
-	hint: Disable or modify the sparsity rules if you intend to update such entries.
+	hint: If you intend to update such entries, try one of the following:
+	hint: * Use the --sparse option.
+	hint: * Disable or modify the sparsity rules.
 	hint: Disable this message with \"git config advice.updateSparsePath false\"
 	EOF
 

t/t3705-add-sparse-checkout.sh

@@ -44,12 +44,15 @@ test_sparse_entry_unstaged () {
 
 test_expect_success 'setup' "
 	cat >sparse_error_header <<-EOF &&
-	The following pathspecs didn't match any eligible path, but they do match index
-	entries outside the current sparse checkout:
+	The following paths and/or pathspecs matched paths that exist
+	outside of your sparse-checkout definition, so will not be
+	updated in the index:
 	EOF
 
 	cat >sparse_hint <<-EOF &&
-	hint: Disable or modify the sparsity rules if you intend to update such entries.
+	hint: If you intend to update such entries, try one of the following:
+	hint: * Use the --sparse option.
+	hint: * Disable or modify the sparsity rules.
 	hint: Disable this message with \"git config advice.updateSparsePath false\"
 	EOF
 

t/t7002-mv-sparse-checkout.sh

@@ -11,12 +11,15 @@ test_expect_success 'setup' "
 	git commit -m files &&
 
 	cat >sparse_error_header <<-EOF &&
-	The following pathspecs didn't match any eligible path, but they do match index
-	entries outside the current sparse checkout:
+	The following paths and/or pathspecs matched paths that exist
+	outside of your sparse-checkout definition, so will not be
+	updated in the index:
 	EOF
 
 	cat >sparse_hint <<-EOF
-	hint: Disable or modify the sparsity rules if you intend to update such entries.
+	hint: If you intend to update such entries, try one of the following:
+	hint: * Use the --sparse option.
+	hint: * Disable or modify the sparsity rules.
 	hint: Disable this message with \"git config advice.updateSparsePath false\"
 	EOF
 "