Python testing

Host-side Python tests in Fuchsia are executed via fx test, CI, and CQ using the Fuchsia-vendored Python interpreter (fuchsia-vendored-python).

Defining a Host Test

Use the python_host_test GN template to define a test target.

Test .py files must use the standard shebang:

#!/usr/bin/env fuchsia-vendored-python

Example BUILD.gn

import("//build/python/python_host_test.gni")

if (is_host) {
  python_host_test("my_script_test") {
    main_source = "my_script_test.py"
    sources = [ "test_helper.py" ]
    libraries = [ "//path/to/library:lib" ]
  }
}

group("tests") {
  testonly = true
  public_deps = [ ":my_script_test($host_toolchain)" ]
}

Key GN Parameters

• main_source: (Required) Path to the primary .py test entry point.
• libraries: (Optional) List of python_library labels imported by the test.
• enable_mypy: (Optional) Enables MyPy static type checking. Defaults to true.

Running Tests

Run tests locally using fx test:

fx test //path/to/my_test:my_script_test