fetch: add 'refs/bundle/' to log.excludeDecoration

When fetching from a bundle URI, the branches of that bundle are stored
in a different ref namespace: refs/bundles/. This namespace is intended
to assist with later 'git fetch' negotiations with a Git server,
allowing the client to advertise which data it already has from a bundle
URI.

These references can be confusing for a user when they appear as a
decoration in 'git log' output. Add "refs/bundles/" to the multi-valued
log.excludeDecoration config value. This is similar to the way
"refs/prefetch/" is hidden by background prefetch operations in 'git
maintenance' as added by 96eaffe (maintenance: set
log.excludeDecoration durin prefetch, 2021-01-19).

Signed-off-by: Derrick Stolee <derrickstolee@github.com>

Documentation/fetch-options.txt

@@ -321,4 +321,5 @@ endif::git-pull[]
 --bundle-uri=<uri>::
 	Instead of fetching from a remote, fetch a bundle from the given
 	`<uri>` and unbundle the data into the local repository. The refs
-	in the bundle will be stored under the `refs/bundle/*` namespace.
+	in the bundle will be stored under the hidden `refs/bundle/*`
+	namespace.

bundle-uri.c

@@ -1,6 +1,7 @@
 #include "cache.h"
 #include "bundle-uri.h"
 #include "bundle.h"
+#include "config.h"
 #include "object-store.h"
 #include "refs.h"
 #include "run-command.h"
@@ -153,6 +154,12 @@ int fetch_bundle_uri(struct repository *r, const char *uri)
 	if ((result = unbundle_from_file(r, filename.buf)))
 		goto cleanup;
 
+	git_config_set_multivar_gently("log.excludedecoration",
+					"refs/bundle/",
+					"refs/bundle/",
+					CONFIG_FLAGS_FIXED_VALUE |
+					CONFIG_FLAGS_MULTI_REPLACE);
+
 cleanup:
 	unlink(filename.buf);
 	strbuf_release(&filename);

t/t5558-fetch-bundle-uri.sh

@@ -28,15 +28,19 @@ test_expect_success 'fetch file bundle' '
 	git -C fetch-to fetch --bundle-uri="$(pwd)/fetch-from/B.bundle" &&
 	git -C fetch-to rev-parse refs/bundles/topic >actual &&
 	git -C fetch-from rev-parse topic >expect &&
-	test_cmp expect actual
+	test_cmp expect actual &&
+
+	test_config -C fetch-to log.excludedecoration refs/bundle/
 '
 
 test_expect_success 'fetch file:// bundle' '
 	git init fetch-file &&
 	git -C fetch-file fetch --bundle-uri="file://$(pwd)/fetch-from/B.bundle" &&
 	git -C fetch-file rev-parse refs/bundles/topic >actual &&
 	git -C fetch-from rev-parse topic >expect &&
-	test_cmp expect actual
+	test_cmp expect actual &&
+
+	test_config -C fetch-file log.excludedecoration refs/bundle/
 '
 
 #########################################################################
@@ -62,7 +66,9 @@ test_expect_success 'fetch HTTP bundle' '
 	git -C fetch-http fetch --bundle-uri="$HTTPD_URL/B.bundle" &&
 	git -C fetch-http rev-parse refs/bundles/topic >actual &&
 	git -C fetch-from rev-parse topic >expect &&
-	test_cmp expect actual
+	test_cmp expect actual &&
+
+	test_config log.excludedecoration refs/bundle/
 '
 
 # Do not add tests here unless they use the HTTP server, as they will