Allow the user to interactively enable additional languages when creating a project via CLI

Resolves #768

pyproject.toml

@@ -253,6 +253,7 @@ ignore = [
   "C400",     # wants to unnecessarily force use of list comprehension
   "UP037",    # can incorrectly (!) convert quoted type to unquoted type, causing an error
   "UP045",    # imposes T | None instead of Optional[T]
+  "UP031",    # forbids % operator to format strings
 ]
 unfixable = ["F841", "F601", "F602", "B018"]
 extend-fixable = ["F401", "B905", "W291"]

src/serena/cli.py

@@ -441,8 +441,11 @@ class ProjectCommands(AutoRegisteringGroup):
                     raise ValueError(f"Unknown language '{lang}'. Supported: {all_langs}")
 
         generated_conf = ProjectConfig.autogenerate(
-            project_root=project_path, project_name=name, languages=languages if languages else None
+            project_root=project_path, project_name=name, languages=languages if languages else None, interactive=True
         )
+        yml_path = ProjectConfig.path_to_project_yml(project_path)
+        languages_str = ", ".join([lang.value for lang in generated_conf.languages]) if generated_conf.languages else "N/A"
+        click.echo(f"Generated project with languages {{{languages_str}}} at {yml_path}.")
         return generated_conf
 
     @staticmethod
@@ -462,10 +465,7 @@ class ProjectCommands(AutoRegisteringGroup):
     @click.option("--timeout", type=float, default=10, help="Timeout for indexing a single file (only used if --index is set).")
     def create(project_path: str, name: str | None, language: tuple[str, ...], index: bool, log_level: str, timeout: float) -> None:
         try:
-            generated_conf = ProjectCommands._create_project(project_path, name, language)
-            yml_path = os.path.join(project_path, ProjectConfig.rel_path_to_project_yml())
-            click.echo(f"Generated project.yml with languages {generated_conf.languages} at {yml_path}.")
-
+            ProjectCommands._create_project(project_path, name, language)
             if index:
                 click.echo("Indexing project...")
                 ProjectCommands._index_project(project_path, log_level, timeout=timeout)
@@ -497,8 +497,7 @@ class ProjectCommands(AutoRegisteringGroup):
         if not os.path.exists(yml_path):
             click.echo(f"Project configuration not found at {yml_path}. Auto-creating...")
             try:
-                generated_conf = ProjectCommands._create_project(project, name, language)
-                click.echo(f"Generated project.yml with languages {generated_conf.languages} at {yml_path}.")
+                ProjectCommands._create_project(project, name, language)
             except FileExistsError:
                 # Race condition - file was created between check and creation
                 pass

src/serena/config/serena_config.py

@@ -34,6 +34,7 @@ from solidlsp.ls_config import Language
 
 from ..analytics import RegisteredTokenCountEstimator
 from ..util.class_decorators import singleton
+from ..util.cli_util import ask_yes_no
 
 if TYPE_CHECKING:
     from ..project import Project
@@ -113,7 +114,12 @@ class ProjectConfig(ToolInclusionDefinition, ToStringMixin):
 
     @classmethod
     def autogenerate(
-        cls, project_root: str | Path, project_name: str | None = None, languages: list[Language] | None = None, save_to_disk: bool = True
+        cls,
+        project_root: str | Path,
+        project_name: str | None = None,
+        languages: list[Language] | None = None,
+        save_to_disk: bool = True,
+        interactive: bool = False,
     ) -> Self:
         """
         Autogenerate a project configuration for a given project root.
@@ -123,6 +129,7 @@ class ProjectConfig(ToolInclusionDefinition, ToStringMixin):
             containing the project
         :param languages: the languages of the project; if None, they will be determined automatically
         :param save_to_disk: whether to save the project configuration to disk
+        :param interactive: whether to run in interactive CLI mode, asking the user for input where appropriate
         :return: the project configuration
         """
         project_root = Path(project_root).resolve()
@@ -131,6 +138,7 @@ class ProjectConfig(ToolInclusionDefinition, ToStringMixin):
         with LogTime("Project configuration auto-generation", logger=log):
             project_name = project_name or project_root.name
             if languages is None:
+                # determine languages automatically
                 language_composition = determine_programming_language_composition(str(project_root))
                 if len(language_composition) == 0:
                     raise ValueError(
@@ -143,18 +151,40 @@ class ProjectConfig(ToolInclusionDefinition, ToStringMixin):
                         f"  project_name: {project_name}\n"
                         f"  language: python  # or typescript, java, csharp, rust, go, ruby, cpp, php, swift, elixir, terraform, bash\n"
                     )
-                # find the language with the highest percentage
-                dominant_language = max(language_composition.keys(), key=lambda lang: language_composition[lang])
-                languages_to_use = [dominant_language]
+                # sort languages by number of files found
+                languages_and_percentages = sorted(language_composition.items(), key=lambda item: item[1], reverse=True)
+                # find the language with the highest percentage and enable it
+                top_language_pair = languages_and_percentages[0]
+                other_language_pairs = languages_and_percentages[1:]
+                languages_to_use = [top_language_pair[0]]
+                # if in interactive mode, ask the user which other languages to enable
+                if len(other_language_pairs) > 0 and interactive:
+                    print(
+                        "Detected and enabled main language '%s' (%.2f%% of source files)." % (top_language_pair[0], top_language_pair[1])
+                    )
+                    print(f"Additionally detected {len(other_language_pairs)} other language(s).\n")
+                    print("Note: Enable only languages you need symbolic retrieval/editing capabilities for.")
+                    print("      Additional language servers use resources and some languages may require additional")
+                    print("      system-level installations/configuration (see Serena documentation).")
+                    print("\nWhich additional languages do you want to enable?")
+                    for lang, perc in other_language_pairs:
+                        enable = ask_yes_no("Enable %s (%.2f%% of source files)?" % (lang, perc), default=False)
+                        if enable:
+                            languages_to_use.append(lang)
+                    print()
             else:
                 languages_to_use = [lang.value for lang in languages]
             config_with_comments = cls.load_commented_map(PROJECT_TEMPLATE_FILE)
             config_with_comments["project_name"] = project_name
             config_with_comments["languages"] = languages_to_use
             if save_to_disk:
-                save_yaml(str(project_root / cls.rel_path_to_project_yml()), config_with_comments, preserve_comments=True)
+                save_yaml(cls.path_to_project_yml(project_root), config_with_comments, preserve_comments=True)
             return cls._from_dict(config_with_comments)
 
+    @classmethod
+    def path_to_project_yml(cls, project_root: str | Path) -> str:
+        return os.path.join(project_root, cls.rel_path_to_project_yml())
+
     @classmethod
     def rel_path_to_project_yml(cls) -> str:
         return os.path.join(SERENA_MANAGED_DIR_NAME, cls.SERENA_DEFAULT_PROJECT_FILE)

src/serena/util/cli_util.py

@@ -0,0 +1,12 @@
+def ask_yes_no(question: str, default: bool | None = None) -> bool:
+    default_prompt = "Y/n" if default else "y/N"
+
+    while True:
+        answer = input(f"{question} [{default_prompt}] ").strip().lower()
+        if answer == "" and default is not None:
+            return default
+        if answer in ("y", "yes"):
+            return True
+        if answer in ("n", "no"):
+            return False
+        print("Please answer yes/y or no/n.")

test/serena/test_cli_project_commands.py

@@ -57,7 +57,7 @@ class TestProjectCreate:
         """Test basic project creation with explicit language."""
         result = cli_runner.invoke(ProjectCommands.create, [temp_project_dir, "--language", "python"])
         assert result.exit_code == 0, f"Command failed: {result.output}"
-        assert "Generated project.yml" in result.output
+        assert "Generated project" in result.output
         assert "python" in result.output.lower()
 
         # Verify project.yml was created
@@ -68,7 +68,7 @@ class TestProjectCreate:
         """Test project creation with auto-detected language."""
         result = cli_runner.invoke(ProjectCommands.create, [temp_project_dir_with_python_file])
         assert result.exit_code == 0, f"Command failed: {result.output}"
-        assert "Generated project.yml" in result.output
+        assert "Generated project" in result.output
         assert "python" in result.output.lower()
 
         # Verify project.yml was created
@@ -79,7 +79,7 @@ class TestProjectCreate:
         """Test project creation with custom name and explicit language."""
         result = cli_runner.invoke(ProjectCommands.create, [temp_project_dir, "--name", "my-custom-project", "--language", "python"])
         assert result.exit_code == 0, f"Command failed: {result.output}"
-        assert "Generated project.yml" in result.output
+        assert "Generated project" in result.output
 
         # Verify project.yml was created
         yml_path = os.path.join(temp_project_dir, ".serena", "project.yml")
@@ -89,7 +89,7 @@ class TestProjectCreate:
         """Test project creation with specified language."""
         result = cli_runner.invoke(ProjectCommands.create, [temp_project_dir, "--language", "python"])
         assert result.exit_code == 0, f"Command failed: {result.output}"
-        assert "Generated project.yml" in result.output
+        assert "Generated project" in result.output
         assert "python" in result.output.lower()
 
     def test_create_with_multiple_languages(self, cli_runner, temp_project_dir):
@@ -99,7 +99,7 @@ class TestProjectCreate:
             [temp_project_dir, "--language", "python", "--language", "typescript"],
         )
         assert result.exit_code == 0, f"Command failed: {result.output}"
-        assert "Generated project.yml" in result.output
+        assert "Generated project" in result.output
 
     def test_create_with_invalid_language(self, cli_runner, temp_project_dir):
         """Test project creation with invalid language raises error."""
@@ -129,7 +129,7 @@ class TestProjectCreate:
             [temp_project_dir_with_python_file, "--language", "python", "--index", "--log-level", "ERROR", "--timeout", "5"],
         )
         assert result.exit_code == 0, f"Command failed: {result.output}"
-        assert "Generated project.yml" in result.output
+        assert "Generated project" in result.output
         assert "Indexing project" in result.output
 
         # Verify project.yml was created
@@ -144,7 +144,7 @@ class TestProjectCreate:
         """Test that project creation without --index does NOT perform indexing."""
         result = cli_runner.invoke(ProjectCommands.create, [temp_project_dir, "--language", "python"])
         assert result.exit_code == 0
-        assert "Generated project.yml" in result.output
+        assert "Generated project" in result.output
         assert "Indexing" not in result.output
 
         # Verify cache directory was NOT created