#!/bin/bash
#
# Copyright 2015 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.
#
# Testing environment for the Bazel integration tests
#
# TODO(bazel-team): This file is currently an append of the old testenv.sh and
# test-setup.sh files. This must be cleaned up eventually.

# TODO(bazel-team): Factor each test suite's is-this-windows setup check to use
# this var instead, or better yet a common $IS_WINDOWS var.
PLATFORM="$(uname -s | tr [:upper:] [:lower:])"

function is_darwin() {
  [[ "${PLATFORM}" =~ darwin ]]
}

function _log_base() {
  prefix=$1
  shift
  echo >&2 "${prefix}[$(basename "$0") $(date "+%Y-%m-%d %H:%M:%S (%z)")] $*"
}

function log_info() {
  _log_base "INFO" "$@"
}

function log_fatal() {
  _log_base "ERROR" "$@"
  exit 1
}

if ! type rlocation &> /dev/null; then
  log_fatal "rlocation() is undefined"
fi

# Set some environment variables needed on Windows.
if [[ $PLATFORM =~ msys ]]; then
  # TODO(philwo) remove this once we have a Bazel release that includes the CL
  # moving the Windows-specific TEST_TMPDIR into TestStrategy.
  TEST_TMPDIR_BASENAME="$(basename "$TEST_TMPDIR")"

  export JAVA_HOME="${JAVA_HOME:-$(ls -d C:/Program\ Files/Java/jdk* | sort | tail -n 1)}"
  export BAZEL_SH="$(cygpath -m /usr/bin/bash)"
fi

# Make the command "bazel" available for tests.
if [ -z "${BAZEL_SUFFIX:-}" ]; then
  PATH_TO_BAZEL_BIN=$(rlocation "io_bazel/src/bazel")
  PATH_TO_BAZEL_WRAPPER="$(dirname $(rlocation "io_bazel/src/test/shell/bin/bazel"))"
else
  DIR_OF_BAZEL_BIN="$(dirname $(rlocation "io_bazel/src/bazel${BAZEL_SUFFIX}"))"
  ln -s "${DIR_OF_BAZEL_BIN}/bazel${BAZEL_SUFFIX}" "${DIR_OF_BAZEL_BIN}/bazel"
  PATH_TO_BAZEL_WRAPPER="$(dirname $(rlocation "io_bazel/src/test/shell/bin/bazel${BAZEL_SUFFIX}"))"
  ln -s "${PATH_TO_BAZEL_WRAPPER}/bazel${BAZEL_SUFFIX}" "${PATH_TO_BAZEL_WRAPPER}/bazel"
  PATH_TO_BAZEL_BIN="${DIR_OF_BAZEL_BIN}/bazel"
fi
# Convert PATH_TO_BAZEL_WRAPPER to Unix path style on Windows, because it will be
# added into PATH. There's problem if PATH=C:/msys64/usr/bin:/usr/local,
# because ':' is used as both path separator and in C:/msys64/...
case "$(uname -s | tr [:upper:] [:lower:])" in
msys*|mingw*|cygwin*)
  PATH_TO_BAZEL_WRAPPER="$(cygpath -u "$PATH_TO_BAZEL_WRAPPER")"
esac
[ ! -f "${PATH_TO_BAZEL_WRAPPER}/bazel" ] \
  && log_fatal "Unable to find the Bazel binary at $PATH_TO_BAZEL_WRAPPER/bazel"
export PATH="$PATH_TO_BAZEL_WRAPPER:$PATH"

################### shell/bazel/testenv ##################################
# Setting up the environment for Bazel integration tests.
#
[ -z "$TEST_SRCDIR" ] && log_fatal "TEST_SRCDIR not set!"
BAZEL_RUNFILES="$TEST_SRCDIR/io_bazel"

# WORKSPACE file
workspace_file="${BAZEL_RUNFILES}/WORKSPACE"
distdir_bzl_file="${BAZEL_RUNFILES}/distdir.bzl"

# Java
if [[ $PLATFORM =~ msys ]]; then
  jdk_dir="$(cygpath -m $(cd $(rlocation local_jdk/bin/java.exe)/../..; pwd))"
else
  jdk_dir="${TEST_SRCDIR}/local_jdk"
fi
langtools="$(rlocation io_bazel/src/test/shell/bazel/langtools.jar)"

# Tools directory location
tools_dir="$(dirname $(rlocation io_bazel/tools/BUILD))"
langtools_dir="$(dirname $(rlocation io_bazel/third_party/java/jdk/langtools/BUILD))"

# Sandbox tools
process_wrapper="${BAZEL_RUNFILES}/src/main/tools/process-wrapper"
linux_sandbox="${BAZEL_RUNFILES}/src/main/tools/linux-sandbox"

# Test data
testdata_path=${BAZEL_RUNFILES}/src/test/shell/bazel/testdata
python_server="${BAZEL_RUNFILES}/src/test/shell/bazel/testing_server.py"

# Third-party
protoc_compiler="${BAZEL_RUNFILES}/src/test/shell/integration/protoc"

if [ -z ${RUNFILES_MANIFEST_ONLY+x} ]; then
  junit_jar="${BAZEL_RUNFILES}/third_party/junit/junit-*.jar"
  hamcrest_jar="${BAZEL_RUNFILES}/third_party/hamcrest/hamcrest-*.jar"
else
  junit_jar=$(rlocation io_bazel/third_party/junit/junit-.*.jar)
  hamcrest_jar=$(rlocation io_bazel/third_party/hamcrest/hamcrest-.*.jar)
fi


function use_bazel_workspace_file() {
  mkdir -p src/test/shell/bazel
  cat >src/test/shell/bazel/list_source_repository.bzl <<EOF
def list_source_repository(name):
  pass
EOF
  touch src/test/shell/bazel/BUILD
  rm -f WORKSPACE distdir.bzl
  ln -sf ${workspace_file} WORKSPACE
  touch BUILD
  ln -sf ${distdir_bzl_file} distdir.bzl
}

# This function copies the tools directory from Bazel.
function copy_tools_directory() {
  cp -RL ${tools_dir}/* tools
  if [ -f tools/jdk/BUILD ]; then
    chmod +w tools/jdk/BUILD
  fi
  if [ -f tools/build_defs/repo/BUILD.repo ]; then
      cp tools/build_defs/repo/BUILD.repo tools/build_defs/repo/BUILD
  fi
  # To support custom langtools
  cp ${langtools} tools/jdk/langtools.jar
  cat >>tools/jdk/BUILD <<'EOF'
filegroup(name = "test-langtools", srcs = ["langtools.jar"])
EOF

  mkdir -p third_party/java/jdk/langtools
  cp -R ${langtools_dir}/* third_party/java/jdk/langtools

  chmod -R +w .

  mkdir -p third_party/py/gflags
  cat > third_party/py/gflags/BUILD <<EOF
licenses(["notice"])
package(default_visibility = ["//visibility:public"])

py_library(
    name = "gflags",
)
EOF
}

# Report whether a given directory name corresponds to a tools directory.
function is_tools_directory() {
  case "$1" in
    third_party|tools|src)
      true
      ;;
    *)
      false
      ;;
  esac
}

# Copy the examples of the base workspace
function copy_examples() {
  EXAMPLE="$(cd $(dirname $(rlocation io_bazel/examples/cpp/BUILD))/..; pwd)"
  cp -RL ${EXAMPLE} .
  chmod -R +w .
}

#
# Find a random unused TCP port
#
pick_random_unused_tcp_port () {
    perl -MSocket -e '
sub CheckPort {
  my ($port) = @_;
  socket(TCP_SOCK, PF_INET, SOCK_STREAM, getprotobyname("tcp"))
    || die "socket(TCP): $!";
  setsockopt(TCP_SOCK, SOL_SOCKET, SO_REUSEADDR, 1)
    || die "setsockopt(TCP): $!";
  return 0 unless bind(TCP_SOCK, sockaddr_in($port, INADDR_ANY));
  socket(UDP_SOCK, PF_INET, SOCK_DGRAM, getprotobyname("udp"))
    || die "socket(UDP): $!";
  return 0 unless bind(UDP_SOCK, sockaddr_in($port, INADDR_ANY));
  return 1;
}
for (1 .. 128) {
  my ($port) = int(rand() * 27000 + 32760);
  if (CheckPort($port)) {
    print "$port\n";
    exit 0;
  }
}
print "NO_FREE_PORT_FOUND\n";
exit 1;
'
}

#
# A uniform SHA-256 command that works across platforms.
#
# sha256sum is the fastest option, but may not be available on macOS (where it
# is usually called 'gsha256sum'), so we optionally fallback to shasum.
#
if hash sha256sum 2>/dev/null; then
  :
elif hash gsha256sum 2>/dev/null; then
  function sha256sum() {
    gsha256sum "$@"
  }
elif hash shasum 2>/dev/null; then
  function sha256sum() {
    shasum -a 256 "$@"
  }
else
  echo "testenv.sh: Could not find either sha256sum or gsha256sum or shasum in your PATH."
  exit 1
fi

################### shell/bazel/test-setup ###############################
# Setup bazel for integration tests
#

# OS X has a limit in the pipe length, so force the root to a shorter one
bazel_root="${TEST_TMPDIR}/root"

# Delete stale installation directory from previously failed tests. On Windows
# we regularly get the same TEST_TMPDIR but a failed test may only partially
# clean it up, and the next time the test runs, Bazel reports a corrupt
# installation error. See https://github.com/bazelbuild/bazel/issues/3618
rm -rf "${bazel_root}"
mkdir -p "${bazel_root}"

bazel_javabase="${jdk_dir}"

log_info "bazel binary is at $PATH_TO_BAZEL_WRAPPER"

# Here we unset variable that were set by the invoking Blaze instance
unset JAVA_RUNFILES

# Runs a command, retrying if needed for a fixed timeout.
#
# Necessary to use it on Windows, typically when deleting directory trees,
# because the OS cannot delete open files, which we attempt to do when deleting
# workspaces where a Bazel server is still in the middle of shutting down.
# (Because "bazel shutdown" returns sooner than the server actually shuts down.)
function try_with_timeout() {
  for i in {1..120}; do
    if $* ; then
      break
    fi
    if (( i == 10 )) || (( i == 30 )) || (( i == 60 )) ; then
      log_info "try_with_timeout($*): no success after $i seconds" \
               "(timeout in $((120-i)) seconds)"
    fi
    sleep 1
  done
}

function setup_bazelrc() {
  cat >$TEST_TMPDIR/bazelrc <<EOF
# Set the user root properly for this test invocation.
startup --output_user_root=${bazel_root}

# Print all progress messages because we regularly grep the output in tests.
common --show_progress_rate_limit=-1

# Disable terminal-specific features.
common --color=no --curses=no

# TODO(#7899): Remove once we flip the flag default.
build --incompatible_use_python_toolchains=true

${EXTRA_BAZELRC:-}
EOF

  if [[ -n ${REPOSITORY_CACHE:-} ]]; then
    echo "testenv.sh: Using repository cache at $REPOSITORY_CACHE."
    cat >>$TEST_TMPDIR/bazelrc <<EOF
sync --repository_cache=$REPOSITORY_CACHE --experimental_repository_cache_hardlinks
fetch --repository_cache=$REPOSITORY_CACHE --experimental_repository_cache_hardlinks
build --repository_cache=$REPOSITORY_CACHE --experimental_repository_cache_hardlinks
query --repository_cache=$REPOSITORY_CACHE --experimental_repository_cache_hardlinks
EOF
  fi

  if [[ -n ${INSTALL_BASE:-} ]]; then
    echo "testenv.sh: Using shared install base at $INSTALL_BASE."
    echo "startup --install_base=$INSTALL_BASE" >> $TEST_TMPDIR/bazelrc
  fi
}

function setup_android_sdk_support() {
  ANDROID_SDK=$PWD/android_sdk
  SDK_SRCDIR=$TEST_SRCDIR/androidsdk
  mkdir -p $ANDROID_SDK
  for i in $SDK_SRCDIR/*; do
    ln -s "$i" "$ANDROID_SDK/$(basename $i)"
  done
cat >> WORKSPACE <<EOF
android_sdk_repository(
    name = "androidsdk",
    path = "$ANDROID_SDK",
)
EOF
}

function setup_android_ndk_support() {
  ANDROID_NDK=$PWD/android_ndk
  NDK_SRCDIR=$TEST_SRCDIR/androidndk/ndk
  mkdir -p $ANDROID_NDK
  for i in $NDK_SRCDIR/*; do
    if [[ "$(basename $i)" != "BUILD" ]]; then
      ln -s "$i" "$ANDROID_NDK/$(basename $i)"
    fi
  done
  cat >> WORKSPACE <<EOF
android_ndk_repository(
    name = "androidndk",
    path = "$ANDROID_NDK",
)
EOF
}

function setup_javatest_common() {
  # TODO(bazel-team): we should use remote repositories.
  mkdir -p third_party
  if [ ! -f third_party/BUILD ]; then
    cat <<EOF >third_party/BUILD
package(default_visibility = ["//visibility:public"])
EOF
  fi

  [ -e third_party/junit.jar ] || ln -s ${junit_jar} third_party/junit.jar
  [ -e third_party/hamcrest.jar ] \
    || ln -s ${hamcrest_jar} third_party/hamcrest.jar
}

function setup_javatest_support() {
  setup_javatest_common
  grep -q 'name = "junit4"' third_party/BUILD \
    || cat <<EOF >>third_party/BUILD
java_import(
    name = "junit4",
    jars = [
        "junit.jar",
        "hamcrest.jar",
    ],
)
EOF
}

# If the current platform is Windows, defines a Python toolchain for our
# Windows CI machines. Otherwise does nothing.
#
# Our Windows CI machines have Python 2 and 3 installed at C:\Python2 and
# C:\Python3 respectively.
#
# Since the tools directory is not cleared between test cases, this only needs
# to run once per suite. However, the toolchain must still be registered
# somehow.
#
# TODO(#7844): Delete this custom (and machine-specific) test setup once we have
# an autodetecting Python toolchain for Windows.
function maybe_setup_python_windows_tools() {
  if [[ ! $PLATFORM =~ msys ]]; then
    return
  fi

  mkdir -p tools/python/windows
  cat > tools/python/windows/BUILD << EOF
load("@bazel_tools//tools/python:toolchain.bzl", "py_runtime_pair")

py_runtime(
  name = "py2_runtime",
  interpreter_path = r"C:\Python2\python.exe",
  python_version = "PY2",
)

py_runtime(
  name = "py3_runtime",
  interpreter_path = r"C:\Python3\python.exe",
  python_version = "PY3",
)

py_runtime_pair(
  name = "py_runtime_pair",
  py2_runtime = ":py2_runtime",
  py3_runtime = ":py3_runtime",
)

toolchain(
  name = "py_toolchain",
  toolchain = ":py_runtime_pair",
  toolchain_type = "@bazel_tools//tools/python:toolchain_type",
  target_compatible_with = ["@platforms//os:windows"],
)
EOF
}

function setup_skylark_javatest_support() {
  setup_javatest_common
  grep -q "name = \"junit4-jars\"" third_party/BUILD \
    || cat <<EOF >>third_party/BUILD
filegroup(
    name = "junit4-jars",
    srcs = [
        "junit.jar",
        "hamcrest.jar",
    ],
)
EOF
}

# Sets up Objective-C tools. Mac only.
function setup_objc_test_support() {
  IOS_SDK_VERSION=$(xcrun --sdk iphoneos --show-sdk-version)
}

function setup_skylib_support() {
  # Get skylib path portably by using rlocation to locate a top-level file in
  # the repo. Use BUILD because it's in the //:test_deps target (unlike
  # WORKSPACE).
  local -r skylib_workspace="$(rlocation bazel_skylib/BUILD)"
  [[ -n "$skylib_workspace" && -e "$skylib_workspace" ]] || fail "could not find Skylib"
  local -r skylib_root="$(dirname "$skylib_workspace")"
  cat >> WORKSPACE << EOF
new_local_repository(
    name = 'bazel_skylib',
    build_file_content = '',
    path='$skylib_root',
)
EOF
}

function add_rules_cc_to_workspace() {
  cat >> "$1"<<EOF
load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")

http_archive(
    name = "rules_cc",
    sha256 = "36fa66d4d49debd71d05fba55c1353b522e8caef4a20f8080a3d17cdda001d89",
    strip_prefix = "rules_cc-0d5f3f2768c6ca2faca0079a997a97ce22997a0c",
    urls = [
        "https://mirror.bazel.build/github.com/bazelbuild/rules_cc/archive/0d5f3f2768c6ca2faca0079a997a97ce22997a0c.zip",
        "https://github.com/bazelbuild/rules_cc/archive/0d5f3f2768c6ca2faca0079a997a97ce22997a0c.zip",
    ],
)
EOF
}

# TODO(https://github.com/bazelbuild/bazel/issues/8986): Build this dynamically
# from //WORKSPACE
function add_rules_pkg_to_workspace() {
  cat >> "$1"<<EOF
load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")

http_archive(
    name = "rules_pkg",
    sha256 = "5bdc04987af79bd27bc5b00fe30f59a858f77ffa0bd2d8143d5b31ad8b1bd71c",
    urls = [
        "https://mirror.bazel.build/github.com/bazelbuild/rules_pkg/rules_pkg-0.2.0.tar.gz",
        "https://github.com/bazelbuild/rules_pkg/releases/download/0.2.0/rules_pkg-0.2.0.tar.gz",
    ],
)
EOF
}

function create_workspace_with_default_repos() {
  touch "$1"
  add_rules_cc_to_workspace "$1"
  add_rules_pkg_to_workspace "$1"
  echo "$1"
}

# Write the default WORKSPACE file, wiping out any custom WORKSPACE setup.
function write_workspace_file() {
  cat > WORKSPACE << EOF
workspace(name = '$WORKSPACE_NAME')
EOF
  add_rules_cc_to_workspace "WORKSPACE"
  add_rules_pkg_to_workspace "WORKSPACE"

  maybe_setup_python_windows_workspace
}

# If the current platform is Windows, registers our custom Windows Python
# toolchain. Otherwise does nothing.
#
# Since this modifies the WORKSPACE file, it must be called between test cases.
function maybe_setup_python_windows_workspace() {
  if [[ ! $PLATFORM =~ msys ]]; then
    return
  fi

  # --extra_toolchains has left-to-right precedence semantics, but the bazelrc
  # is processed before the command line. This means that any matching
  # toolchains added to the bazelrc will always take precedence over toolchains
  # set up by test cases. Instead, we add the toolchain to WORKSPACE so that it
  # has lower priority than whatever is passed on the command line.
  cat >> WORKSPACE << EOF
register_toolchains("//tools/python/windows:py_toolchain")
EOF
}

workspaces=()
# Set-up a new, clean workspace with only the tools installed.
function create_new_workspace() {
  new_workspace_dir=${1:-$(mktemp -d ${TEST_TMPDIR}/workspace.XXXXXXXX)}
  try_with_timeout rm -fr ${new_workspace_dir}
  mkdir -p ${new_workspace_dir}
  workspaces+=(${new_workspace_dir})
  cd ${new_workspace_dir}
  mkdir tools
  mkdir -p third_party/java/jdk/langtools

  copy_tools_directory

  [ -e third_party/java/jdk/langtools/javac-9+181-r4173-1.jar ] \
    || ln -s "${langtools_path}"  third_party/java/jdk/langtools/javac-9+181-r4173-1.jar

  write_workspace_file

  maybe_setup_python_windows_tools
}


# Set-up a clean default workspace.
function setup_clean_workspace() {
  export WORKSPACE_DIR=${TEST_TMPDIR}/workspace
  log_info "setting up client in ${WORKSPACE_DIR}" >> $TEST_log
  try_with_timeout rm -fr ${WORKSPACE_DIR}
  create_new_workspace ${WORKSPACE_DIR}
  [ "${new_workspace_dir}" = "${WORKSPACE_DIR}" ] \
    || log_fatal "Failed to create workspace"

  if [[ $PLATFORM =~ msys ]]; then
    export BAZEL_SH="$(cygpath --windows /bin/bash)"
  fi
}

# Clean up all files that are not in tools directories, to restart
# from a clean workspace
function cleanup_workspace() {
  if [ -d "${WORKSPACE_DIR:-}" ]; then
    log_info "Cleaning up workspace" >> $TEST_log
    cd ${WORKSPACE_DIR}
    bazel clean >> "$TEST_log" 2>&1

    for i in *; do
      if ! is_tools_directory "$i"; then
        try_with_timeout rm -fr "$i"
      fi
    done
    write_workspace_file
  fi
  for i in "${workspaces[@]}"; do
    if [ "$i" != "${WORKSPACE_DIR:-}" ]; then
      try_with_timeout rm -fr $i
    fi
  done
  workspaces=()
}

function testenv_tear_down() {
  cleanup_workspace
}

# This is called by unittest.bash upon eventual exit of the test suite.
function cleanup() {
  if [ -d "${WORKSPACE_DIR:-}" ]; then
    # Try to shutdown Bazel at the end to prevent a "Cannot delete path" error
    # on Windows when the outer Bazel tries to delete $TEST_TMPDIR.
    cd "${WORKSPACE_DIR}"
    try_with_timeout bazel shutdown || true
  fi
}

#
# Simples assert to make the tests more readable
#
function assert_build() {
  bazel build -s --verbose_failures $* || fail "Failed to build $*"
}

function assert_build_output() {
  local OUTPUT=$1
  shift
  assert_build "$*"
  test -f "$OUTPUT" || fail "Output $OUTPUT not found for target $*"
}

function assert_build_fails() {
  bazel build -s $1 >> $TEST_log 2>&1 \
    && fail "Test $1 succeed while expecting failure" \
    || true
  if [ -n "${2:-}" ]; then
    expect_log "$2"
  fi
}

function assert_test_ok() {
  bazel test --test_output=errors $* >> $TEST_log 2>&1 \
    || fail "Test $1 failed while expecting success"
}

function assert_test_fails() {
  bazel test --test_output=errors $* >> $TEST_log 2>&1 \
    && fail "Test $* succeed while expecting failure" \
    || true
  expect_log "$1.*FAILED"
}

function assert_binary_run() {
  $1 >> $TEST_log 2>&1 || fail "Failed to run $1"
  [ -z "${2:-}" ] || expect_log "$2"
}

function assert_bazel_run() {
  bazel run $1 >> $TEST_log 2>&1 || fail "Failed to run $1"
    [ -z "${2:-}" ] || expect_log "$2"

  assert_binary_run "./bazel-bin/$(echo "$1" | sed 's|^//||' | sed 's|:|/|')" "${2:-}"
}

setup_bazelrc

################### shell/integration/testenv ############################
# Setting up the environment for our legacy integration tests.
#
PRODUCT_NAME=bazel
TOOLS_REPOSITORY="@bazel_tools"
WORKSPACE_NAME=main
bazelrc=$TEST_TMPDIR/bazelrc

function put_bazel_on_path() {
  # do nothing as test-setup already does that
  true
}

function write_default_bazelrc() {
  setup_bazelrc
}

function add_to_bazelrc() {
  echo "$@" >> $bazelrc
}

function create_and_cd_client() {
  setup_clean_workspace
  touch .bazelrc
}

################### Extra ############################

# Functions that need to be called before each test.

create_and_cd_client

# Optional environment changes.

# Creates a fake Python default runtime that just outputs a marker string
# indicating which version was used, without executing any Python code.
function use_fake_python_runtimes_for_testsuite() {
  # The stub script template automatically appends ".exe" to the Python binary
  # name if it doesn't already end in ".exe", ".com", or ".bat".
  if [[ $PLATFORM =~ msys ]]; then
    PYTHON2_FILENAME="python2.bat"
    PYTHON3_FILENAME="python3.bat"
  else
    PYTHON2_FILENAME="python2.sh"
    PYTHON3_FILENAME="python3.sh"
  fi

  add_to_bazelrc "build --extra_toolchains=//tools/python:fake_python_toolchain"

  mkdir -p tools/python

  cat > tools/python/BUILD << EOF
load("@bazel_tools//tools/python:toolchain.bzl", "py_runtime_pair")

package(default_visibility=["//visibility:public"])

sh_binary(
    name = '2to3',
    srcs = ['2to3.sh']
)

py_runtime(
    name = "fake_py2_interpreter",
    interpreter = ":${PYTHON2_FILENAME}",
    python_version = "PY2",
)

py_runtime(
    name = "fake_py3_interpreter",
    interpreter = ":${PYTHON3_FILENAME}",
    python_version = "PY3",
)

py_runtime_pair(
    name = "fake_py_runtime_pair",
    py2_runtime = ":fake_py2_interpreter",
    py3_runtime = ":fake_py3_interpreter",
)

toolchain(
    name = "fake_python_toolchain",
    toolchain = ":fake_py_runtime_pair",
    toolchain_type = "@bazel_tools//tools/python:toolchain_type",
)
EOF

  # Windows .bat has uppercase ECHO and no shebang.
  if [[ $PLATFORM =~ msys ]]; then
    cat > tools/python/$PYTHON2_FILENAME << EOF
@ECHO I am Python 2
EOF
    cat > tools/python/$PYTHON3_FILENAME << EOF
@ECHO I am Python 3
EOF
  else
    cat > tools/python/$PYTHON2_FILENAME << EOF
#!/bin/sh
echo 'I am Python 2'
EOF
    cat > tools/python/$PYTHON3_FILENAME << EOF
#!/bin/sh
echo 'I am Python 3'
EOF
    chmod +x tools/python/$PYTHON2_FILENAME tools/python/$PYTHON3_FILENAME
  fi
}