scalar: work around GVFS Protocol HTTP/2 failures

Work around failures when using the GVFS Protocol with Azure DevOps URLs
(dev.azure.com and *.visualstudio.com) due to incomplete HTTP/2 support
on the server side. Configure http.<url>.version=HTTP/1.1 for these
remotes when setting up or reconfiguring a Scalar enlistment.

This ensures that Scalar and GVFS continue to function correctly with
Azure-hosted repositories, without affecting other remotes.

This fixes #752

Co-authored-by: Johannes Schindelin <[email protected]>
Signed-off-by: Johannes Schindelin <[email protected]>

Author: Copilot

scalar.c

@@ -230,6 +230,31 @@ static int set_recommended_config(int reconfigure)
 				     fsmonitor.key, fsmonitor.value);
 	}
 
+	/*
+	 * Set HTTP/1.1 for Azure DevOps URLs
+	 * We check for dev.azure.com and .visualstudio.com/ patterns
+	 * which are sufficient to identify ADO URLs
+	 */
+	if (!git_config_get_string("remote.origin.url", &value)) {
+		if (starts_with(value, "https://dev.azure.com") ||
+		    strstr(value, ".visualstudio.com/")) {
+			struct strbuf key = STRBUF_INIT;
+			strbuf_addf(&key, "http.%s.version", value);
+			FREE_AND_NULL(value);
+
+			if (reconfigure || git_config_get_string(key.buf, &value)) {
+				trace2_data_string("scalar", the_repository, key.buf, "created");
+				if (git_config_set_gently(key.buf, "HTTP/1.1") < 0) {
+					strbuf_release(&key);
+					return error(_("could not configure %s=%s"),
+						     key.buf, "HTTP/1.1");
+				}
+			}
+			strbuf_release(&key);
+		} else {
+		}
+	}
+
 	/*
 	 * The `log.excludeDecoration` setting is special because it allows
 	 * for multiple values.
@@ -886,7 +911,7 @@ static int cmd_clone(int argc, const char **argv)
 			cache_server_url = default_cache_server_url;
 		if (set_config("core.useGVFSHelper=true") ||
 		    set_config("core.gvfs=150") ||
-		    set_config("http.version=HTTP/1.1")) {
+		    set_config("http.%s.version=HTTP/1.1", url)) {
 			res = error(_("could not turn on GVFS helper"));
 			goto cleanup;
 		}

t/t9210-scalar.sh

@@ -247,6 +247,29 @@ test_expect_success 'scalar reconfigure --all with detached HEADs' '
 	done
 '
 
+test_expect_success 'verify http.<url>.version=HTTP/1.1 for ADO URLs' '
+	test_when_finished rm -rf test-http-url-config &&
+
+	# Create a test repository
+	git init test-http-url-config &&
+
+	# Test both URL types in a loop
+	for url in "https://dev.azure.com/test/project/_git/repo" \
+		   "https://contoso.visualstudio.com/project/_git/repo"
+	do
+		# Set URL as remote
+		git -C test-http-url-config config set remote.origin.url "$url" &&
+
+		# Run scalar reconfigure
+		scalar reconfigure test-http-url-config &&
+
+		# Verify URL-specific HTTP version setting
+		git -C test-http-url-config config "http.$url.version" >actual &&
+		echo "HTTP/1.1" >expect &&
+		test_cmp expect actual || return 1
+	done
+'
+
 test_expect_success '`reconfigure -a` removes stale config entries' '
 	git init stale/src &&
 	scalar register stale &&
@@ -386,6 +409,11 @@ test_expect_success '`scalar clone` with GVFS-enabled server' '
 	git -C using-gvfs/src config gvfs.sharedCache >actual &&
 	test_cmp expect actual &&
 
+	: verify that URL-specific HTTP version setting is configured for GVFS URLs in clone &&
+	git -C using-gvfs/src config "http.http://$HOST_PORT/.version" >actual &&
+	echo "HTTP/1.1" >expect &&
+	test_cmp expect actual &&
+
 	second=$(git rev-parse --verify second:second.t) &&
 	(
 		cd using-gvfs/src &&