src/test/shell/integration/python_stub_test.sh

#!/bin/bash
#
# Copyright 2019 The Bazel Authors. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

# --- begin runfiles.bash initialization ---
set -euo pipefail
if [[ ! -d "${RUNFILES_DIR:-/dev/null}" && ! -f "${RUNFILES_MANIFEST_FILE:-/dev/null}" ]]; then
  if [[ -f "$0.runfiles_manifest" ]]; then
    export RUNFILES_MANIFEST_FILE="$0.runfiles_manifest"
  elif [[ -f "$0.runfiles/MANIFEST" ]]; then
    export RUNFILES_MANIFEST_FILE="$0.runfiles/MANIFEST"
  elif [[ -f "$0.runfiles/bazel_tools/tools/bash/runfiles/runfiles.bash" ]]; then
    export RUNFILES_DIR="$0.runfiles"
  fi
fi
if [[ -f "${RUNFILES_DIR:-/dev/null}/bazel_tools/tools/bash/runfiles/runfiles.bash" ]]; then
  source "${RUNFILES_DIR}/bazel_tools/tools/bash/runfiles/runfiles.bash"
elif [[ -f "${RUNFILES_MANIFEST_FILE:-/dev/null}" ]]; then
  source "$(grep -m1 "^bazel_tools/tools/bash/runfiles/runfiles.bash " \
            "$RUNFILES_MANIFEST_FILE" | cut -d ' ' -f 2-)"
else
  echo >&2 "ERROR: cannot find @bazel_tools//tools/bash/runfiles:runfiles.bash"
  exit 1
fi
# --- end runfiles.bash initialization ---

source "$(rlocation "io_bazel/src/test/shell/integration_test_setup.sh")" \
  || { echo "integration_test_setup.sh not found!" >&2; exit 1; }

case "$(uname -s | tr [:upper:] [:lower:])" in
msys*|mingw*|cygwin*)
  declare -r is_windows=true
  ;;
*)
  declare -r is_windows=false
  ;;
esac

if "$is_windows"; then
  export MSYS_NO_PATHCONV=1
  export MSYS2_ARG_CONV_EXCL="*"
  declare -r EXE_EXT=".exe"
else
  declare -r EXE_EXT=""
fi

# Tests in this file do not actually start a Python interpreter, but plug in a
# fake stub executable to serve as the "interpreter".

use_fake_python_runtimes_for_testsuite

#### TESTS #############################################################

# Tests that Python 2 or Python 3 is actually invoked, with and without flag
# overrides.
function test_python_version() {
  mkdir -p test
  touch test/main2.py test/main3.py
  cat > test/BUILD << EOF
py_binary(name = "main2",
    default_python_version = "PY2",
    srcs = ['main2.py'],
)
py_binary(name = "main3",
    default_python_version = "PY3",
    srcs = ["main3.py"],
)
EOF

  # No flag, use the default from the rule.
  bazel run //test:main2 \
      &> $TEST_log || fail "bazel run failed"
  expect_log "I am Python 2"
  bazel run //test:main3 \
      &> $TEST_log || fail "bazel run failed"
  expect_log "I am Python 3"

  # Force to Python 2.
  bazel run //test:main2 --force_python=PY2 \
      &> $TEST_log || fail "bazel run failed"
  expect_log "I am Python 2"
  bazel run //test:main3 --force_python=PY2 \
      &> $TEST_log || fail "bazel run failed"
  expect_log "I am Python 2"

  # Force to Python 3.
  bazel run //test:main2 --force_python=PY3 \
      &> $TEST_log || fail "bazel run failed"
  expect_log "I am Python 3"
  bazel run //test:main3 --force_python=PY3 \
      &> $TEST_log || fail "bazel run failed"
  expect_log "I am Python 3"
}

function test_can_build_py_library_at_top_level_regardless_of_version() {
  mkdir -p test
  cat > test/BUILD << EOF
py_library(
    name = "lib2",
    srcs = ["lib2.py"],
    srcs_version = "PY2ONLY",
)
py_library(
    name = "lib3",
    srcs = ["lib3.py"],
    srcs_version = "PY3ONLY",
)
EOF
  touch test/lib2.py test/lib3.py

  EXPFLAG="--incompatible_allow_python_version_transitions=true"

  bazel build --python_version=PY2 $EXPFLAG //test:* \
      &> $TEST_log || fail "bazel build failed"
  bazel build --python_version=PY3 $EXPFLAG //test:* \
      &> $TEST_log || fail "bazel build failed"
}

run_suite "Tests for the Python rules without Python execution"