Fix for BaseUrl in C# base class not being used

src/NSwag.CodeGeneration.CSharp.Tests/CSharpClientSettingsTests.cs

@@ -89,6 +89,31 @@ public async Task WhenUsingBaseUrl_ButNoProperty_ThenPropertyIsNotUsedAndFieldIs
             Assert.Contains("string _baseUrl", code);
         }
 
+        [Fact]
+        public async Task WhenUsingBaseUrl_ButNoPropertyWithBaseClass_ThenPropertyIsUsedAndFieldIsNotGenerated()
+        {
+            // Arrange
+            var swaggerGenerator = new WebApiOpenApiDocumentGenerator(new WebApiOpenApiDocumentGeneratorSettings
+            {
+                SchemaSettings = new NewtonsoftJsonSchemaGeneratorSettings()
+            });
+
+            var document = await swaggerGenerator.GenerateForControllerAsync<FooController>();
+            var generator = new CSharpClientGenerator(document, new CSharpClientGeneratorSettings
+            {
+                UseBaseUrl = true,
+                GenerateBaseUrlProperty = false,
+                ClientBaseClass = "MyBaseClass"
+            });
+
+            // Act
+            var code = generator.GenerateFile();
+
+            // Assert
+            Assert.Contains("BaseUrl", code);
+            Assert.DoesNotContain("string _baseUrl", code);
+        }
+
         [Fact]
         public async Task When_parameter_name_is_reserved_keyword_then_it_is_appended_with_at()
         {

src/NSwag.CodeGeneration.CSharp/Templates/Client.Class.liquid

@@ -3,10 +3,12 @@
 {{ ClientClassAccessModifier }} partial class {{ Class }} {% if HasBaseType %}: {% endif %}{% if HasBaseClass %}{{ BaseClass }}{% if GenerateClientInterfaces %}, {% endif %}{% endif %}{% if GenerateClientInterfaces %}I{{ Class }}{% endif %}
 {
 {% if UseBaseUrl -%}
+{%     if HasBaseClass == false or GenerateBaseUrlProperty == true -%}
     #pragma warning disable 8618
     private string _baseUrl;
     #pragma warning restore 8618
 
+{%     endif -%}
 {% endif -%}
 {% if InjectHttpClient -%}
     private {{ HttpClientType }} _httpClient;
@@ -34,7 +36,7 @@
     public {{ Class }}({{ constructorParameters }}){% if HasConfigurationClass and HasBaseClass -%}{{ " : base(configuration)"}}{% endif %}
 #pragma warning restore CS8618 // Non-nullable field must contain a non-null value when exiting constructor. Consider declaring as nullable.
     {
-{%     if UseBaseUrl -%}
+{%      if UseBaseUrl and HasBaseClass == false and GenerateBaseUrlProperty == true -%}
 {%         if HasBaseUrl -%}
 {%             if GenerateBaseUrlProperty -%}
         BaseUrl = "{{ BaseUrl }}";
@@ -290,7 +292,11 @@
 {%     endif -%}
 
                 var urlBuilder_ = new System.Text.StringBuilder();
-                {% if UseBaseUrl %}if (!string.IsNullOrEmpty(_baseUrl)) urlBuilder_.Append(_baseUrl);{% endif %}
+{%              if HasBaseClass == true and GenerateBaseUrlProperty == false -%}
+                if (!string.IsNullOrEmpty(BaseUrl)) urlBuilder_.Append(BaseUrl);
+{%              else -%}
+                if (!string.IsNullOrEmpty(_baseUrl)) urlBuilder_.Append(_baseUrl);
+{%              endif -%}
                 // Operation Path: "{{ operation.Path }}"
 {%     if operation.Path contains "{" -%}
 {%        assign pathParts = operation.Path | split: "{" -%}