src/test/shell/integration/skylark_flag_test.sh

#!/bin/bash
#
# Copyright 2017 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.

# Tests that the Skylark interpreter is reading flags passed in on the command
# line, in several different evaluation contexts.
#
# The --internal_skylark_flag_test_canary flag is built into
# StarlarkSemanticsOptions specifically for this test suite.

# --- begin runfiles.bash initialization ---
# Copy-pasted from Bazel's Bash runfiles library (tools/bash/runfiles/runfiles.bash).
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; }

# `uname` returns the current platform, e.g "MSYS_NT-10.0" or "Linux".
# `tr` converts all upper case letters to lower case.
# `case` matches the result if the `uname | tr` expression to string prefixes
# that use the same wildcards as names do in Bash, i.e. "msys*" matches strings
# starting with "msys", and "*" matches everything (it's the default case).
case "$(uname -s | tr [:upper:] [:lower:])" in
msys*)
  # As of 2018-08-14, Bazel on Windows only supports MSYS Bash.
  declare -r is_windows=true
  ;;
*)
  declare -r is_windows=false
  ;;
esac

if "$is_windows"; then
  # Disable MSYS path conversion that converts path-looking command arguments to
  # Windows paths (even if they arguments are not in fact paths).
  export MSYS_NO_PATHCONV=1
  export MSYS2_ARG_CONV_EXCL="*"
fi

# Text that will be appended to every print() output when the flag is enabled.
MARKER="<== skylark flag test ==>"

sanity_fail_msg="Marker string '$MARKER' was seen even though "
sanity_fail_msg+="--internal_skylark_flag_test_canary wasn't passed"


function test_build_file() {
  local -r pkg=$FUNCNAME
  mkdir -p $pkg
  cat > $pkg/BUILD <<'EOF' || fail "couldn't create file"
print("In BUILD: ")

genrule(
    name = "dummy",
    cmd = "echo 'dummy' >$@",
    outs = ["dummy.txt"],
)
EOF

  # Sanity check.
  bazel build //$pkg:dummy \
      &>"$TEST_log" || fail "bazel build failed";
  expect_log "In BUILD: " "Did not find BUILD print output"
  expect_not_log "$MARKER" "$sanity_fail_msg"

  bazel build //$pkg:dummy \
      --internal_skylark_flag_test_canary \
      &>"$TEST_log" || fail "bazel build failed";
  expect_log "In BUILD: $MARKER" \
      "Starlark flags are not propagating to BUILD file evaluation"
}

function test_bzl_file_and_macro() {
  local -r pkg=$FUNCNAME
  mkdir -p $pkg
  cat > $pkg/BUILD <<'EOF' || fail "couldn't create file"
load(":test.bzl", "macro")

macro()
EOF
  cat >$pkg/test.bzl <<'EOF' || fail "couldn't create file"
print("In bzl: ")

def macro():
  print("In macro: ")
  native.genrule(
      name = "dummy",
      cmd = "echo 'dummy' >$@",
      outs = ["dummy.txt"],
  )
EOF

  # Sanity check.
  bazel build //$pkg:dummy \
      &>"$TEST_log" || fail "bazel build failed";
  expect_log "In bzl: " "Did not find .bzl print output"
  expect_log "In macro: " "Did not find macro print output"
  expect_not_log "$MARKER" "$sanity_fail_msg"

  bazel build //$pkg:dummy \
      --internal_skylark_flag_test_canary \
      &>"$TEST_log" || fail "bazel build failed";
  expect_log "In bzl: $MARKER" \
      "Starlark flags are not propagating to .bzl file evaluation"
  expect_log "In macro: $MARKER" \
      "Starlark flags are not propagating to macro evaluation"
}

function test_rule() {
  local -r pkg=$FUNCNAME
  mkdir -p $pkg
  cat > $pkg/BUILD <<'EOF' || fail "couldn't create file"
load(":test.bzl", "some_rule")

some_rule(
    name = "dummy",
)
EOF
  cat >$pkg/test.bzl <<'EOF' || fail "couldn't create file"
def _rule_impl(ctx):
  print("In rule: ")

some_rule = rule(
    implementation = _rule_impl,
)
EOF

  # Sanity check.
  bazel build //$pkg:dummy \
      &>"$TEST_log" || fail "bazel build failed";
  expect_log "In rule: " "Did not find rule print output"
  expect_not_log "$MARKER" "$sanity_fail_msg"

  bazel build //$pkg:dummy \
      --internal_skylark_flag_test_canary \
      &>"$TEST_log" || fail "bazel build failed";
  expect_log "In rule: $MARKER" \
      "Starlark flags are not propagating to rule implementation function evaluation"
}

# TODO(brandjon): Once we're no long dropping print() output in computed default
# functions, also test that we're propagating flags there. Alternatively, this
# could be tested by having conditional code that crashes while evaluating the
# Skylark function iff the flag is set.

function test_aspect() {
  local -r pkg=$FUNCNAME
  mkdir -p $pkg
  cat > $pkg/BUILD <<'EOF' || fail "couldn't create file"
load(":test.bzl", "some_rule")

some_rule(
    name = "dummy",
)
EOF
  cat >$pkg/test.bzl <<'EOF' || fail "couldn't create file"
def _rule_impl(ctx):
  pass

some_rule = rule(
    implementation = _rule_impl,
)

def _aspect_impl(target, ctx):
  print("In aspect: ")
  return []

some_aspect = aspect(
    implementation = _aspect_impl,
)
EOF

  # Sanity check.
  bazel build //$pkg:dummy --aspects $pkg/test.bzl%some_aspect \
      &>"$TEST_log" || fail "bazel build failed";
  expect_log "In aspect: " "Did not find aspect print output"
  expect_not_log "$MARKER" "$sanity_fail_msg"

  bazel build //$pkg:dummy --aspects $pkg/test.bzl%some_aspect \
      --internal_skylark_flag_test_canary \
      &>"$TEST_log" || fail "bazel build failed";
  expect_log "In aspect: $MARKER" \
      "Starlark flags are not propagating to aspect implementation function evaluation"
}


run_suite "skylark_flag_test"