Add conan version as separated command (#13999)

* Add conan version command

Signed-off-by: Uilian Ries <uilianries@gmail.com>

* Print python version as well

Signed-off-by: Uilian Ries <uilianries@gmail.com>

* don't reinvent the wheel - print_serial

Signed-off-by: Uilian Ries <uilianries@gmail.com>

* adjust tests

Signed-off-by: Uilian Ries <uilianries@gmail.com>

* strip new lines

Signed-off-by: Uilian Ries <uilianries@gmail.com>

* better format for testing conan version

Signed-off-by: Uilian Ries <uilianries@gmail.com>

---------

Signed-off-by: Uilian Ries <uilianries@gmail.com>

conan/cli/commands/version.py

@@ -0,0 +1,21 @@
+from conan.cli.commands.list import print_serial
+from conan.cli.command import conan_command
+from conan.cli.formatters import default_json_formatter
+from conan import conan_version
+import platform
+import sys
+
+
+@conan_command(group="Consumer", formatters={"text": print_serial, "json": default_json_formatter})
+def version(conan_api, parser, *args):
+    """
+    Give information about the Conan client version.
+    """
+
+    return {'version': str(conan_version),
+            'python': {
+                'version': platform.python_version().replace('\n', ''),
+                'sys_version': sys.version.replace('\n', ''),
+                }
+            }
+

conans/test/integration/command_v2/test_version.py

@@ -0,0 +1,52 @@
+from conans.test.utils.tools import TestClient
+from conan import __version__
+import json
+import platform
+import sys
+
+
+def _python_version():
+    return platform.python_version().replace("\n", "")
+
+
+def _sys_version():
+    return sys.version.replace("\n", "")
+
+
+def test_version_json():
+    """
+    Conan version command should be able to output a json with the version and python version.
+    """
+    t = TestClient()
+    t.run("version --format=json")
+    js = json.loads(t.stdout)
+    assert js["version"] == __version__
+    assert js["python"]["version"] == _python_version()
+    assert js["python"]["sys_version"] == _sys_version()
+
+
+def test_version_text():
+    """
+    Conan version command should be able to output a raw text with the version and python version.
+    """
+    t = TestClient()
+    t.run("version --format=text")
+    _validate_text_output(t.out)
+
+
+def test_version_raw():
+    """
+    Conan version command should be able to output a raw text with the version and python version,
+    when no format is specified.
+    """
+    t = TestClient()
+    t.run("version")
+    _validate_text_output(t.out)
+
+
+def _validate_text_output(output):
+    lines = output.splitlines()
+    assert f'version: {__version__}' in lines
+    assert 'python' in lines
+    assert f'  version: {_python_version()}' in lines
+    assert f'  sys_version: {_sys_version()}' in lines