diff --git a/pkg/gui/custom_commands.go b/pkg/gui/custom_commands.go
index e9aeedb4f..7ae1da8c0 100644
--- a/pkg/gui/custom_commands.go
+++ b/pkg/gui/custom_commands.go
@@ -117,7 +117,8 @@ func (gui *Gui) menuPrompt(prompt config.CustomCommandPrompt, promptResponses []
 
 	return gui.createMenu(title, menuItems, createMenuOptions{showCancel: true})
 }
-func (gui *Gui) generateMenuCandidates(commandOutput string, filter string, format string) ([]string, error) {
+
+func (gui *Gui) GenerateMenuCandidates(commandOutput string, filter string, format string) ([]string, error) {
 	candidates := []string{}
 	reg, err := regexp.Compile(filter)
 	if err != nil {
@@ -138,7 +139,7 @@ func (gui *Gui) generateMenuCandidates(commandOutput string, filter string, form
 			for groupIdx, group := range reg.SubexpNames() {
 				// Record matched group with group ids
 				matchName := "group_" + strconv.Itoa(groupIdx)
-				tmplData[matchName] = group
+				tmplData[matchName] =  out[0][groupIdx]
 				// Record last named group non-empty matches as group matches
 				if group != "" {
 					tmplData[group] = out[0][groupIdx]
@@ -176,7 +177,10 @@ func (gui *Gui) menuPromptFromCommand(prompt config.CustomCommandPrompt, promptR
 	}
 
 	// Need to make a menu out of what the cmd has displayed
-	candidates, err := gui.generateMenuCandidates(message, filter, prompt.Format)
+	candidates, err := gui.GenerateMenuCandidates(message, filter, prompt.Format)
+	if err != nil {
+		return gui.surfaceError(err)
+	}
 
 	menuItems := make([]*menuItem, len(candidates))
 	for i := range candidates {
diff --git a/pkg/gui/dummies.go b/pkg/gui/dummies.go
new file mode 100644
index 000000000..97a03d784
--- /dev/null
+++ b/pkg/gui/dummies.go
@@ -0,0 +1,21 @@
+package gui
+
+import (
+	"github.com/jesseduffield/lazygit/pkg/config"
+	"github.com/jesseduffield/lazygit/pkg/utils"
+	"github.com/jesseduffield/lazygit/pkg/commands/oscommands"
+	"github.com/jesseduffield/lazygit/pkg/commands"
+	"github.com/jesseduffield/lazygit/pkg/i18n"
+	"github.com/jesseduffield/lazygit/pkg/updates"
+)
+
+// NewDummyGui creates a new dummy GUI for testing
+func NewDummyUpdater() *updates.Updater {
+    DummyUpdater, _ := updates.NewUpdater(utils.NewDummyLog(), config.NewDummyAppConfig(), oscommands.NewDummyOSCommand(), i18n.NewTranslationSet(utils.NewDummyLog()))
+    return DummyUpdater
+}
+
+func NewDummyGui() *Gui {
+        DummyGui, _ := NewGui(utils.NewDummyLog(), commands.NewDummyGitCommand(), oscommands.NewDummyOSCommand(), i18n.NewTranslationSet(utils.NewDummyLog()), config.NewDummyAppConfig(), NewDummyUpdater(), "", false)
+	return DummyGui
+}
diff --git a/pkg/gui/gui_test.go b/pkg/gui/gui_test.go
index 8e37cecfe..8fcf0d4de 100644
--- a/pkg/gui/gui_test.go
+++ b/pkg/gui/gui_test.go
@@ -80,3 +80,52 @@ func runCmdHeadless(cmd *exec.Cmd) error {
 
 	return f.Close()
 }
+
+func TestGuiGenerateMenuCandidates(t *testing.T) {
+	type scenario struct {
+		testName string
+		cmdOut   string
+		filter   string
+                format   string
+		test     func([]string, error)
+	}
+
+	scenarios := []scenario{
+		{
+			"Extract remote branch name",
+                        "upstream/pr-1",
+                        "upstream/(?P<branch>.*)",
+                        "{{ .branch }}",
+			func(actual []string, err error) {
+                            assert.NoError(t, err)
+                            assert.EqualValues(t, "pr-1", actual[0])
+			},
+		},
+		{
+			"Multiple named groups",
+                        "upstream/pr-1",
+                        "(?P<remote>[a-z]*)/(?P<branch>.*)",
+                        "{{ .branch }}|{{ .remote }}",
+			func(actual []string, err error) {
+                            assert.NoError(t, err)
+                            assert.EqualValues(t, "pr-1|upstream", actual[0])
+			},
+		},
+		{
+			"Multiple named groups with group ids",
+                        "upstream/pr-1",
+                        "(?P<remote>[a-z]*)/(?P<branch>.*)",
+                        "{{ .group_2 }}|{{ .group_1 }}",
+			func(actual []string, err error) {
+                            assert.NoError(t, err)
+                            assert.EqualValues(t, "pr-1|upstream", actual[0])
+			},
+		},
+	}
+
+	for _, s := range scenarios {
+		t.Run(s.testName, func(t *testing.T) {
+			s.test(NewDummyGui().GenerateMenuCandidates(s.cmdOut, s.filter, s.format))
+		})
+	}
+}