Merge branch 'mt/grep-submodule-textconv'

"git grep --recurse-submodules" takes trees and blobs from the
submodule repository, but the textconv settings when processing a
blob from the submodule is not taken from the submodule repository.
A test is added to demonstrate the issue, without fixing it.

* mt/grep-submodule-textconv:
  grep: demonstrate bug with textconv attributes and submodules

grep.h

@@ -128,9 +128,9 @@ struct grep_opt {
 	 * instead.
 	 *
 	 * This is potentially the cause of at least one bug - "git grep"
-	 * ignoring the textconv attributes from submodules. See [1] for more
-	 * information.
-	 * [1] https://lore.kernel.org/git/CAHd-oW5iEQarYVxEXoTG-ua2zdoybTrSjCBKtO0YT292fm0NQQ@mail.gmail.com/
+	 * using the textconv attributes from the superproject on the
+	 * submodules. See the failing "git grep --textconv" tests in
+	 * t7814-grep-recurse-submodules.sh for more information.
 	 */
 	struct repository *repo;
 

t/t7814-grep-recurse-submodules.sh

@@ -441,4 +441,107 @@ test_expect_success 'grep --recurse-submodules with --cached ignores worktree mo
 	test_must_fail git grep --recurse-submodules --cached "A modified line in submodule" >actual 2>&1 &&
 	test_must_be_empty actual
 '
+
+test_expect_failure 'grep --textconv: superproject .gitattributes does not affect submodules' '
+	reset_and_clean &&
+	test_config_global diff.d2x.textconv "sed -e \"s/d/x/\"" &&
+	echo "a diff=d2x" >.gitattributes &&
+
+	cat >expect <<-\EOF &&
+	a:(1|2)x(3|4)
+	EOF
+	git grep --textconv --recurse-submodules x >actual &&
+	test_cmp expect actual
+'
+
+test_expect_failure 'grep --textconv: superproject .gitattributes (from index) does not affect submodules' '
+	reset_and_clean &&
+	test_config_global diff.d2x.textconv "sed -e \"s/d/x/\"" &&
+	echo "a diff=d2x" >.gitattributes &&
+	git add .gitattributes &&
+	rm .gitattributes &&
+
+	cat >expect <<-\EOF &&
+	a:(1|2)x(3|4)
+	EOF
+	git grep --textconv --recurse-submodules x >actual &&
+	test_cmp expect actual
+'
+
+test_expect_failure 'grep --textconv: superproject .git/info/attributes does not affect submodules' '
+	reset_and_clean &&
+	test_config_global diff.d2x.textconv "sed -e \"s/d/x/\"" &&
+	super_attr="$(git rev-parse --git-path info/attributes)" &&
+	test_when_finished "rm -f \"$super_attr\"" &&
+	echo "a diff=d2x" >"$super_attr" &&
+
+	cat >expect <<-\EOF &&
+	a:(1|2)x(3|4)
+	EOF
+	git grep --textconv --recurse-submodules x >actual &&
+	test_cmp expect actual
+'
+
+# Note: what currently prevents this test from passing is not that the
+# .gitattributes file from "./submodule" is being ignored, but that it is being
+# propagated to the nested "./submodule/sub" files.
+#
+test_expect_failure 'grep --textconv correctly reads submodule .gitattributes' '
+	reset_and_clean &&
+	test_config_global diff.d2x.textconv "sed -e \"s/d/x/\"" &&
+	echo "a diff=d2x" >submodule/.gitattributes &&
+
+	cat >expect <<-\EOF &&
+	submodule/a:(1|2)x(3|4)
+	EOF
+	git grep --textconv --recurse-submodules x >actual &&
+	test_cmp expect actual
+'
+
+test_expect_failure 'grep --textconv correctly reads submodule .gitattributes (from index)' '
+	reset_and_clean &&
+	test_config_global diff.d2x.textconv "sed -e \"s/d/x/\"" &&
+	echo "a diff=d2x" >submodule/.gitattributes &&
+	git -C submodule add .gitattributes &&
+	rm submodule/.gitattributes &&
+
+	cat >expect <<-\EOF &&
+	submodule/a:(1|2)x(3|4)
+	EOF
+	git grep --textconv --recurse-submodules x >actual &&
+	test_cmp expect actual
+'
+
+test_expect_failure 'grep --textconv correctly reads submodule .git/info/attributes' '
+	reset_and_clean &&
+	test_config_global diff.d2x.textconv "sed -e \"s/d/x/\"" &&
+
+	submodule_attr="$(git -C submodule rev-parse --path-format=absolute --git-path info/attributes)" &&
+	test_when_finished "rm -f \"$submodule_attr\"" &&
+	echo "a diff=d2x" >"$submodule_attr" &&
+
+	cat >expect <<-\EOF &&
+	submodule/a:(1|2)x(3|4)
+	EOF
+	git grep --textconv --recurse-submodules x >actual &&
+	test_cmp expect actual
+'
+
+test_expect_failure 'grep saves textconv cache in the appropriate repository' '
+	reset_and_clean &&
+	test_config_global diff.d2x_cached.textconv "sed -e \"s/d/x/\"" &&
+	test_config_global diff.d2x_cached.cachetextconv true &&
+	echo "a diff=d2x_cached" >submodule/.gitattributes &&
+
+	# We only read/write to the textconv cache when grepping from an OID,
+	# as the working tree file might have modifications.
+	git grep --textconv --cached --recurse-submodules x &&
+
+	super_textconv_cache="$(git rev-parse --git-path refs/notes/textconv/d2x_cached)" &&
+	sub_textconv_cache="$(git -C submodule rev-parse \
+			--path-format=absolute --git-path refs/notes/textconv/d2x_cached)" &&
+	test_path_is_missing "$super_textconv_cache" &&
+	test_path_is_file "$sub_textconv_cache"
+'
+
 test_done