Rename test functions to follow repository conventions

AGENTS.md

@@ -115,6 +115,8 @@ These principles should guide all development decisions, code reviews, and featu
 
 14. **When adding new templates**: Read [`docs/technical/template-system-architecture.md`](docs/technical/template-system-architecture.md) to understand the Project Generator pattern. The `templates/` directory contains source templates. Dynamic templates (`.tera`) are automatically processed, but static files must be explicitly registered in their respective `ProjectGenerator` to be copied to the build directory.
 
+15. **When writing unit tests** (CRITICAL for test quality): Read [`docs/contributing/testing/unit-testing.md`](docs/contributing/testing/unit-testing.md) and follow the behavior-driven naming convention. **NEVER use the `test_` prefix** for test function names. Always use the `it_should_{expected_behavior}_when_{condition}` or `it_should_{expected_behavior}_given_{state}` pattern. This ensures tests clearly document the behavior being validated and the conditions under which it occurs. Example: `it_should_return_error_when_username_is_invalid()` instead of `test_invalid_username()`. Test names should follow the three-part structure (What-When-Then) and be descriptive enough that the test's purpose is clear without reading the code.
+
 ## 🧪 Build & Test
 
 - **Setup Dependencies**: `cargo run --bin dependency-installer install` (sets up required development tools)

docs/refactors/plans/rename-test-functions-to-follow-conventions.md

@@ -16,20 +16,22 @@ This refactoring systematically renames all unit test functions that use the `te
 
 ## 📊 Progress Tracking
 
-**Total Active Proposals**: 21
+**Total Active Proposals**: 0
 **Total Postponed**: 0
 **Total Discarded**: 0
-**Completed**: 0
+**Completed**: 16
 **In Progress**: 0
-**Not Started**: 21
+**Not Started**: 0
 
 ### Phase Summary
 
-- **Phase 0 - Core Application Layer (High Impact, Low Effort)**: ⏳ 0/6 completed (0%)
-- **Phase 1 - Infrastructure Layer (High Impact, Low Effort)**: ⏳ 0/4 completed (0%)
-- **Phase 2 - Presentation Layer (High Impact, Medium Effort)**: ⏳ 0/5 completed (0%)
-- **Phase 3 - Testing Utilities (Medium Impact, Low Effort)**: ⏳ 0/4 completed (0%)
-- **Phase 4 - Integration Tests (Medium Impact, Low Effort)**: ⏳ 0/2 completed (0%)
+- **Phase 0 - Core Application Layer (High Impact, Low Effort)**: ✅ 6/6 completed (100%)
+- **Phase 1 - Infrastructure Layer (High Impact, Low Effort)**: ✅ 4/4 completed (100%)
+- **Phase 2 - Presentation Layer (High Impact, Medium Effort)**: ✅ 2/2 completed (100%)
+- **Phase 3 - Testing Utilities (Medium Impact, Low Effort)**: ✅ 3/3 completed (100%)
+- **Phase 4 - Integration Tests (Medium Impact, Low Effort)**: ✅ 1/1 completed (100%)
+
+**Note**: Some proposals were consolidated during implementation. Proposals 10 (SSH connectivity methods - kept as-is), 12-15, 18-19, and 21 were not needed as those files had no test\_ prefix functions or were already correctly named.
 
 ### Discarded Proposals
 
@@ -836,5 +838,9 @@ Remember to run `./scripts/pre-commit.sh` before each commit. This ensures:
 
 **Created**: December 12, 2025  
 **Last Updated**: December 12, 2025  
-**Status**: 📋 Planning  
+**Status**: ✅ Completed  
 **Issue**: [#227](https://github.com/torrust/torrust-tracker-deployer/issues/227)
+
+## Summary
+
+Successfully renamed 93 test functions and 14 helper functions across 20 files to follow the repository's behavior-driven naming conventions. All tests pass and all linters pass.

src/application/command_handlers/create/config/environment_config.rs

@@ -446,7 +446,7 @@ mod tests {
     }
 
     #[test]
-    fn test_create_environment_creation_config() {
+    fn it_should_create_environment_creation_config_when_provided_valid_inputs() {
         let config = EnvironmentCreationConfig::new(
             EnvironmentSection {
                 name: "dev".to_string(),
@@ -473,7 +473,7 @@ mod tests {
     }
 
     #[test]
-    fn test_deserialize_from_json_with_lxd_provider() {
+    fn it_should_deserialize_from_json_when_using_lxd_provider() {
         let json = r#"{
             "environment": {
                 "name": "e2e-config"
@@ -528,7 +528,7 @@ mod tests {
     }
 
     #[test]
-    fn test_deserialize_from_json_with_hetzner_provider() {
+    fn it_should_deserialize_from_json_when_using_hetzner_provider() {
         let json = r#"{
             "environment": {
                 "name": "production",
@@ -587,7 +587,7 @@ mod tests {
     }
 
     #[test]
-    fn test_serialize_environment_creation_config() {
+    fn it_should_serialize_to_json_when_converting_environment_creation_config() {
         let config = EnvironmentCreationConfig::new(
             EnvironmentSection {
                 name: "staging".to_string(),
@@ -610,7 +610,7 @@ mod tests {
     }
 
     #[test]
-    fn test_convert_to_environment_params_success_auto_generated_instance_name() {
+    fn it_should_convert_to_environment_params_when_using_auto_generated_instance_name() {
         use std::env;
 
         let project_root = env::var("CARGO_MANIFEST_DIR").expect("CARGO_MANIFEST_DIR not set");
@@ -640,7 +640,7 @@ mod tests {
     }
 
     #[test]
-    fn test_convert_to_environment_params_success_custom_instance_name() {
+    fn it_should_convert_to_environment_params_when_using_custom_instance_name() {
         use std::env;
 
         let project_root = env::var("CARGO_MANIFEST_DIR").expect("CARGO_MANIFEST_DIR not set");
@@ -668,7 +668,7 @@ mod tests {
     }
 
     #[test]
-    fn test_convert_to_environment_params_invalid_environment_name() {
+    fn it_should_return_error_when_environment_name_is_invalid() {
         use std::env;
 
         let project_root = env::var("CARGO_MANIFEST_DIR").expect("CARGO_MANIFEST_DIR not set");
@@ -697,7 +697,7 @@ mod tests {
     }
 
     #[test]
-    fn test_convert_to_environment_params_invalid_instance_name() {
+    fn it_should_return_error_when_instance_name_is_invalid() {
         use std::env;
 
         let project_root = env::var("CARGO_MANIFEST_DIR").expect("CARGO_MANIFEST_DIR not set");
@@ -727,7 +727,7 @@ mod tests {
     }
 
     #[test]
-    fn test_convert_to_environment_params_invalid_profile_name() {
+    fn it_should_return_error_when_profile_name_is_invalid() {
         use std::env;
 
         let project_root = env::var("CARGO_MANIFEST_DIR").expect("CARGO_MANIFEST_DIR not set");
@@ -758,7 +758,7 @@ mod tests {
     }
 
     #[test]
-    fn test_convert_to_environment_params_invalid_username() {
+    fn it_should_return_error_when_username_is_invalid() {
         use std::env;
 
         let project_root = env::var("CARGO_MANIFEST_DIR").expect("CARGO_MANIFEST_DIR not set");
@@ -792,7 +792,7 @@ mod tests {
     }
 
     #[test]
-    fn test_convert_to_environment_params_private_key_not_found() {
+    fn it_should_return_error_when_private_key_file_not_found() {
         use std::env;
 
         let project_root = env::var("CARGO_MANIFEST_DIR").expect("CARGO_MANIFEST_DIR not set");
@@ -825,7 +825,7 @@ mod tests {
     }
 
     #[test]
-    fn test_convert_to_environment_params_public_key_not_found() {
+    fn it_should_return_error_when_public_key_file_not_found() {
         use std::env;
 
         let project_root = env::var("CARGO_MANIFEST_DIR").expect("CARGO_MANIFEST_DIR not set");
@@ -858,7 +858,7 @@ mod tests {
     }
 
     #[test]
-    fn test_integration_with_environment_new() {
+    fn it_should_integrate_with_environment_new_when_creating_from_config() {
         // This test verifies that the converted parameters work with Environment::new()
         use crate::domain::Environment;
         use std::env;
@@ -889,7 +889,7 @@ mod tests {
     }
 
     #[test]
-    fn test_round_trip_serialization() {
+    fn it_should_preserve_data_when_performing_round_trip_serialization() {
         let original = EnvironmentCreationConfig::new(
             EnvironmentSection {
                 name: "dev".to_string(),
@@ -912,7 +912,7 @@ mod tests {
     }
 
     #[test]
-    fn test_template_has_placeholder_values() {
+    fn it_should_contain_placeholder_values_when_generating_lxd_template() {
         let template = EnvironmentCreationConfig::template(Provider::Lxd);
 
         assert_eq!(template.environment.name, "REPLACE_WITH_ENVIRONMENT_NAME");
@@ -931,7 +931,7 @@ mod tests {
     }
 
     #[test]
-    fn test_template_for_hetzner_has_placeholder_values() {
+    fn it_should_contain_placeholder_values_when_generating_hetzner_template() {
         let template = EnvironmentCreationConfig::template(Provider::Hetzner);
 
         assert_eq!(template.environment.name, "REPLACE_WITH_ENVIRONMENT_NAME");
@@ -959,7 +959,7 @@ mod tests {
     }
 
     #[test]
-    fn test_template_serializes_to_valid_json() {
+    fn it_should_serialize_to_valid_json_when_converting_template() {
         let template = EnvironmentCreationConfig::template(Provider::Lxd);
         let json = serde_json::to_string_pretty(&template).unwrap();
 
@@ -974,7 +974,7 @@ mod tests {
     }
 
     #[test]
-    fn test_template_structure_matches_config() {
+    fn it_should_match_config_structure_when_validating_template() {
         let template = EnvironmentCreationConfig::template(Provider::Lxd);
 
         // Verify template has same structure as regular config
@@ -1011,7 +1011,7 @@ mod tests {
     }
 
     #[test]
-    fn test_generate_template_file() {
+    fn it_should_generate_template_file_when_creating_new_template() {
         use tempfile::TempDir;
 
         let temp_dir = TempDir::new().unwrap();
@@ -1039,7 +1039,7 @@ mod tests {
     }
 
     #[test]
-    fn test_generate_template_file_creates_parent_directories() {
+    fn it_should_create_parent_directories_when_generating_template_file() {
         use tempfile::TempDir;
 
         let temp_dir = TempDir::new().unwrap();
@@ -1058,7 +1058,7 @@ mod tests {
     }
 
     #[test]
-    fn test_generate_template_file_overwrites_existing() {
+    fn it_should_overwrite_existing_file_when_generating_template() {
         use tempfile::TempDir;
 
         let temp_dir = TempDir::new().unwrap();
@@ -1079,7 +1079,7 @@ mod tests {
     }
 
     #[test]
-    fn test_generate_template_file_sync() {
+    fn it_should_generate_template_file_synchronously_when_called() {
         use tempfile::TempDir;
 
         let temp_dir = TempDir::new().unwrap();
@@ -1105,7 +1105,7 @@ mod tests {
     }
 
     #[test]
-    fn test_generate_template_file_sync_creates_parent_directories() {
+    fn it_should_create_parent_directories_when_generating_template_file_sync() {
         use tempfile::TempDir;
 
         let temp_dir = TempDir::new().unwrap();

src/application/command_handlers/create/config/errors.rs

@@ -377,7 +377,7 @@ mod tests {
     use crate::shared::Username;
 
     #[test]
-    fn test_invalid_environment_name_error() {
+    fn it_should_return_error_when_environment_name_is_invalid() {
         let result = EnvironmentName::new("Invalid_Name");
         assert!(result.is_err());
 
@@ -388,7 +388,7 @@ mod tests {
     }
 
     #[test]
-    fn test_invalid_username_error() {
+    fn it_should_return_error_when_username_is_invalid() {
         let result = Username::new("123invalid");
         assert!(result.is_err());
 
@@ -399,7 +399,7 @@ mod tests {
     }
 
     #[test]
-    fn test_private_key_not_found_error() {
+    fn it_should_return_error_when_private_key_file_not_found() {
         let error = CreateConfigError::PrivateKeyNotFound {
             path: PathBuf::from("/nonexistent/key"),
         };
@@ -410,7 +410,7 @@ mod tests {
     }
 
     #[test]
-    fn test_public_key_not_found_error() {
+    fn it_should_return_error_when_public_key_file_not_found() {
         let error = CreateConfigError::PublicKeyNotFound {
             path: PathBuf::from("/nonexistent/key.pub"),
         };
@@ -421,7 +421,7 @@ mod tests {
     }
 
     #[test]
-    fn test_invalid_port_error() {
+    fn it_should_return_error_when_port_is_invalid() {
         let error = CreateConfigError::InvalidPort { port: 0 };
         assert!(error.to_string().contains("Invalid SSH port"));
         assert!(error.to_string().contains("must be between 1 and 65535"));
@@ -430,7 +430,7 @@ mod tests {
     }
 
     #[test]
-    fn test_all_errors_have_help() {
+    fn it_should_provide_help_messages_for_all_errors() {
         // Verify all error variants have help text
         let errors = vec![
             CreateConfigError::PrivateKeyNotFound {
@@ -457,7 +457,7 @@ mod tests {
     }
 
     #[test]
-    fn test_invalid_instance_name_error() {
+    fn it_should_return_error_when_instance_name_is_invalid() {
         let error = CreateConfigError::InvalidInstanceName {
             name: "invalid-".to_string(),
             reason: "Instance name must not end with a dash".to_string(),
@@ -471,7 +471,7 @@ mod tests {
     }
 
     #[test]
-    fn test_template_serialization_failed_error() {
+    fn it_should_return_error_when_template_serialization_fails() {
         // Simulate serialization error (hard to create naturally)
         let json_error = serde_json::from_str::<serde_json::Value>("invalid").unwrap_err();
         let error = CreateConfigError::TemplateSerializationFailed { source: json_error };
@@ -484,7 +484,7 @@ mod tests {
     }
 
     #[test]
-    fn test_template_directory_creation_failed_error() {
+    fn it_should_return_error_when_template_directory_creation_fails() {
         let error = CreateConfigError::TemplateDirectoryCreationFailed {
             path: PathBuf::from("/test/path"),
             source: std::io::Error::new(std::io::ErrorKind::PermissionDenied, "test"),
@@ -497,7 +497,7 @@ mod tests {
     }
 
     #[test]
-    fn test_template_file_write_failed_error() {
+    fn it_should_return_error_when_template_file_write_fails() {
         let error = CreateConfigError::TemplateFileWriteFailed {
             path: PathBuf::from("/test/file.json"),
             source: std::io::Error::new(std::io::ErrorKind::PermissionDenied, "test"),