Fix new tty prompt (#897)

Fix #827

---------

Co-authored-by: silverwind <silverwind@noreply.gitea.com>
Reviewed-on: https://gitea.com/gitea/tea/pulls/897
Reviewed-by: silverwind <silverwind@noreply.gitea.com>

modules/context/context_prompt_test.go

@@ -0,0 +1,52 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package context
+
+import (
+	"testing"
+
+	"code.gitea.io/tea/modules/config"
+)
+
+func TestShouldPromptFallbackLogin(t *testing.T) {
+	tests := []struct {
+		name      string
+		login     *config.Login
+		canPrompt bool
+		expected  bool
+	}{
+		{
+			name:      "no login",
+			login:     nil,
+			canPrompt: true,
+			expected:  false,
+		},
+		{
+			name:      "default login",
+			login:     &config.Login{Default: true},
+			canPrompt: true,
+			expected:  false,
+		},
+		{
+			name:      "non-default no prompt",
+			login:     &config.Login{Default: false},
+			canPrompt: false,
+			expected:  false,
+		},
+		{
+			name:      "non-default prompt",
+			login:     &config.Login{Default: false},
+			canPrompt: true,
+			expected:  true,
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			if got := shouldPromptFallbackLogin(test.login, test.canPrompt); got != test.expected {
+				t.Fatalf("expected %v, got %v", test.expected, got)
+			}
+		})
+	}
+}