Add CLI arg to make virtualenvs not autogenerate if needed

conan/api/subapi/install.py

@@ -51,7 +51,7 @@ def install_sources(self, graph, remotes):
 
     # TODO: Look for a better name
     def install_consumer(self, deps_graph, generators=None, source_folder=None, output_folder=None,
-                         deploy=False, deploy_package=None, deploy_folder=None):
+                         deploy=False, deploy_package=None, deploy_folder=None, envs_generation=None):
         """ Once a dependency graph has been installed, there are things to be done, like invoking
         generators for the root consumer.
         This is necessary for example for conanfile.txt/py, or for "conan install <ref> -g
@@ -88,4 +88,4 @@ def install_consumer(self, deps_graph, generators=None, source_folder=None, outp
                 final_generators.append(gen)
         conanfile.generators = final_generators
         app = ConanApp(self.conan_api)
-        write_generators(conanfile, app)
+        write_generators(conanfile, app, envs_generation=envs_generation)

conan/cli/commands/build.py

@@ -29,6 +29,8 @@ def build(conan_api, parser, *args):
                         help="Deployer output folder, base build folder by default if not set")
     parser.add_argument("--build-require", action='store_true', default=False,
                         help='Whether the provided path is a build-require')
+    parser.add_argument("--envs-generation", default=None, choices=["false"],
+                        help="Generation strategy for virtual environment files for the root")
     add_common_install_arguments(parser)
     add_lockfile_args(parser)
     args = parser.parse_args(*args)
@@ -64,7 +66,8 @@ def build(conan_api, parser, *args):
 
     out.title("Finalizing install (deploy, generators)")
     conan_api.install.install_consumer(deps_graph, args.generator, source_folder, output_folder,
-                                       deploy=args.deployer, deploy_folder=deployer_folder)
+                                       deploy=args.deployer, deploy_folder=deployer_folder,
+                                       envs_generation=args.envs_generation)
 
     out.title("Calling build()")
     conanfile = deps_graph.root.conanfile

conan/cli/commands/install.py

@@ -39,6 +39,8 @@ def install(conan_api, parser, *args):
                              "the provided patterns")
     parser.add_argument("--build-require", action='store_true', default=False,
                         help='Whether the provided path is a build-require')
+    parser.add_argument("--envs-generation", default=None, choices=["false"],
+                        help="Generation strategy for virtual environment files for the root")
     args = parser.parse_args(*args)
     validate_common_graph_args(args)
     # basic paths
@@ -74,7 +76,8 @@ def install(conan_api, parser, *args):
     ConanOutput().title("Finalizing install (deploy, generators)")
     conan_api.install.install_consumer(deps_graph, args.generator, source_folder, output_folder,
                                        deploy=args.deployer, deploy_package=args.deployer_package,
-                                       deploy_folder=args.deployer_folder)
+                                       deploy_folder=args.deployer_folder,
+                                       envs_generation=args.envs_generation)
     ConanOutput().success("Install finished successfully")
 
     # Update lockfile if necessary

conan/internal/api/install/generators.py

@@ -70,7 +70,7 @@ def load_cache_generators(path):
     return result
 
 
-def write_generators(conanfile, app):
+def write_generators(conanfile, app, envs_generation=None):
     new_gen_folder = conanfile.generators_folder
     _receive_conf(conanfile)
 
@@ -118,18 +118,20 @@ def write_generators(conanfile, app):
             with conanfile_exception_formatter(conanfile, "generate"):
                 conanfile.generate()
 
-    if conanfile.virtualbuildenv:
-        mkdir(new_gen_folder)
-        with chdir(new_gen_folder):
-            from conan.tools.env.virtualbuildenv import VirtualBuildEnv
-            env = VirtualBuildEnv(conanfile)
-            env.generate()
-    if conanfile.virtualrunenv:
-        mkdir(new_gen_folder)
-        with chdir(new_gen_folder):
-            from conan.tools.env import VirtualRunEnv
-            env = VirtualRunEnv(conanfile)
-            env.generate()
+    if envs_generation is None:
+        if conanfile.virtualbuildenv:
+            mkdir(new_gen_folder)
+            with chdir(new_gen_folder):
+                from conan.tools.env.virtualbuildenv import VirtualBuildEnv
+                env = VirtualBuildEnv(conanfile)
+                # TODO: Check length of env.vars().keys() when adding NotEmpty
+                env.generate()
+        if conanfile.virtualrunenv:
+            mkdir(new_gen_folder)
+            with chdir(new_gen_folder):
+                from conan.tools.env import VirtualRunEnv
+                env = VirtualRunEnv(conanfile)
+                env.generate()
 
     _generate_aggregated_env(conanfile)
 

test/integration/toolchains/env/test_virtualenv_default_apply.py

@@ -22,29 +22,39 @@ def package_info(self):
     return client
 
 
+@pytest.mark.parametrize("scope", ["build", "run"])
 @pytest.mark.parametrize("default_virtualenv", [True, False, None])
-def test_virtualenv_deactivated(client, default_virtualenv):
-    format_str = {True: "virtualbuildenv = True",
-                  False: "virtualbuildenv = False",
+@pytest.mark.parametrize("cli_value", [None, "false"])
+def test_virtualenv_deactivated(client, scope, default_virtualenv, cli_value):
+    format_str = {True: f"virtual{scope}env = True",
+                  False: f"virtual{scope}env = False",
                   None: ""}[default_virtualenv]
     conanfile = textwrap.dedent("""
     from conan import ConanFile
-    import platform
 
     class ConanFileToolsTest(ConanFile):
+        settings = "os"
         {}
         requires = "foo/1.0"
     """).format(format_str)
 
     client.save({"conanfile.py": conanfile})
-    client.run("install . ")
+    cli_extra = f"--envs-generation={cli_value}" if cli_value is not None else ""
+    client.run(f"install . {cli_extra}")
     extension = "bat" if platform.system() == "Windows" else "sh"
-    exists_file = os.path.exists(os.path.join(client.current_folder,
-                                              "conanbuildenv.{}".format(extension)))
-    if default_virtualenv is True or default_virtualenv is None:
-        assert exists_file
-    elif default_virtualenv is False:
-        assert not exists_file
+
+    filename = f"conan{scope}env.{extension}"
+    filepath = os.path.join(client.current_folder, filename)
+
+    exists_file = os.path.exists(filepath)
+
+    should_exist = cli_value != "false" and (default_virtualenv is None or default_virtualenv)
+
+    if should_exist:
+        assert exists_file, f"File {filename} should exist in {os.listdir(client.current_folder)}"
+        assert "Foo" in client.load(filepath)
+    else:
+        assert not exists_file, f"File {filename} should not exist in {os.listdir(client.current_folder)}"
 
 
 def test_virtualrunenv_not_applied(client):