tests/format/variables.py - buildstream - Git at Google

 #
 #  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.
 #

 # Pylint doesn't play well with fixtures and dependency injection from pytest
 # pylint: disable=redefined-outer-name

 import os
 import sys

 import pytest

 from buildstream import _yaml
 from buildstream.exceptions import ErrorDomain, LoadErrorReason
 from buildstream._testing.runcli import cli  # pylint: disable=unused-import

 from tests.testutils.site import pip_sample_packages  # pylint: disable=unused-import
 from tests.testutils.site import SAMPLE_PACKAGES_SKIP_REASON


 # Project directory
 DATA_DIR = os.path.join(os.path.dirname(os.path.realpath(__file__)), "variables")

 # List of BuildStream protected variables
 PROTECTED_VARIABLES = [("project-name"), ("element-name"), ("max-jobs")]


 def print_warning(msg):
     RED, END = "\033[91m", "\033[0m"
     print(("\n{}{}{}").format(RED, msg, END), file=sys.stderr)


 ###############################################################
 #  Test proper loading of some default commands from plugins  #
 ###############################################################
 @pytest.mark.parametrize(
     "target,varname,expected",
     [("autotools.bst", "make-install", 'make -j1 DESTDIR="/buildstream-install" install')],
 )
 @pytest.mark.datafiles(os.path.join(DATA_DIR, "defaults"))
 @pytest.mark.skipif("not pip_sample_packages()", reason=SAMPLE_PACKAGES_SKIP_REASON)
 def test_defaults(cli, datafiles, target, varname, expected):
     project = str(datafiles)
     result = cli.run(project=project, silent=True, args=["show", "--deps", "none", "--format", "%{vars}", target])
     result.assert_success()
     result_vars = _yaml.load_data(result.output)
     assert result_vars.get_str(varname) == expected


 ################################################################
 #  Test overriding of variables to produce different commands  #
 ################################################################
 @pytest.mark.parametrize(
     "target,varname,expected",
     [("autotools.bst", "make-install", 'make -j1 DESTDIR="/custom/install/root" install')],
 )
 @pytest.mark.datafiles(os.path.join(DATA_DIR, "overrides"))
 @pytest.mark.skipif("not pip_sample_packages()", reason=SAMPLE_PACKAGES_SKIP_REASON)
 def test_overrides(cli, datafiles, target, varname, expected):
     project = str(datafiles)
     result = cli.run(project=project, silent=True, args=["show", "--deps", "none", "--format", "%{vars}", target])
     result.assert_success()
     result_vars = _yaml.load_data(result.output)
     assert result_vars.get_str(varname) == expected


 @pytest.mark.parametrize(
     "element,provenance",
     [
         # This test makes a reference to an undefined variable in a build command
         ("manual.bst", "manual.bst [line 5 column 6]"),
         # This test makes a reference to an undefined variable by another variable,
         # ensuring that we validate variables even when they are unused
         ("manual2.bst", "manual2.bst [line 4 column 8]"),
         # This test uses a build command to refer to some variables which ultimately
         # refer to an undefined variable, testing a more complex case.
         ("manual3.bst", "manual3.bst [line 6 column 8]"),
     ],
     ids=["build-command", "variables", "complex"],
 )
 @pytest.mark.datafiles(os.path.join(DATA_DIR, "missing_variables"))
 def test_undefined(cli, datafiles, element, provenance):
     project = str(datafiles)
     result = cli.run(project=project, silent=True, args=["show", "--deps", "none", "--format", "%{config}", element])
     result.assert_main_error(ErrorDomain.LOAD, LoadErrorReason.UNRESOLVED_VARIABLE)
     assert provenance in result.stderr


 @pytest.mark.parametrize(
     "element,provenances",
     [
         # Test a simple a -> b and b -> a reference
         ("simple-cyclic.bst", ["simple-cyclic.bst [line 4 column 5]", "simple-cyclic.bst [line 5 column 5]"]),
         # Test a simple a -> b and b -> a reference with some text involved
         ("cyclic.bst", ["cyclic.bst [line 5 column 10]", "cyclic.bst [line 4 column 5]"]),
         # Test an indirect circular dependency
         (
             "indirect-cyclic.bst",
             [
                 "indirect-cyclic.bst [line 5 column 5]",
                 "indirect-cyclic.bst [line 6 column 5]",
                 "indirect-cyclic.bst [line 7 column 5]",
                 "indirect-cyclic.bst [line 8 column 5]",
             ],
         ),
         # Test an indirect circular dependency
         ("self-reference.bst", ["self-reference.bst [line 4 column 5]"]),
     ],
     ids=["simple", "simple-text", "indirect", "self-reference"],
 )
 @pytest.mark.timeout(30, method="signal")
 @pytest.mark.datafiles(os.path.join(DATA_DIR, "cyclic_variables"))
 def test_circular_reference(cli, datafiles, element, provenances):
     print_warning("Performing cyclic test, if this test times out it will exit the test sequence")
     project = str(datafiles)
     result = cli.run(project=project, silent=True, args=["build", element])
     result.assert_main_error(ErrorDomain.LOAD, LoadErrorReason.CIRCULAR_REFERENCE_VARIABLE)
     for provenance in provenances:
         assert provenance in result.stderr


 # Test that variables which refer to eachother very deeply are
 # still resolved correctly, this ensures that we are not relying
 # on a recursive algorithm limited by stack depth.
 #
 @pytest.mark.parametrize(
     "maxvars",
     [50, 500, 5000],
 )
 @pytest.mark.datafiles(os.path.join(DATA_DIR, "defaults"))
 @pytest.mark.skipif("not pip_sample_packages()", reason=SAMPLE_PACKAGES_SKIP_REASON)
 def test_deep_references(cli, datafiles, maxvars):
     project = str(datafiles)

     # Generate an element with very, very many variables to resolve,
     # each which expand to the value of the previous variable.
     #
     # The bottom variable defines a test value which we check for
     # in the top variable in `bst show` output.
     #
     topvar = "var{}".format(maxvars)
     bottomvar = "var0"
     testvalue = "testvalue {}".format(maxvars)

     # Generate
     variables = {"var{}".format(idx + 1): "%{var" + str(idx) + "}" for idx in range(maxvars)}
     variables[bottomvar] = testvalue
     element = {"kind": "manual", "variables": variables}
     _yaml.roundtrip_dump(element, os.path.join(project, "test.bst"))

     # Run `bst show`
     result = cli.run(project=project, args=["show", "--format", "%{vars}", "test.bst"])
     result.assert_success()

     # Test results
     result_vars = _yaml.load_data(result.output)
     assert result_vars.get_str(topvar) == testvalue


 @pytest.mark.parametrize("protected_var", PROTECTED_VARIABLES)
 @pytest.mark.datafiles(os.path.join(DATA_DIR, "protected-vars"))
 def test_use_of_protected_var_project_conf(cli, datafiles, protected_var):
     project = str(datafiles)
     conf = {"name": "test", "min-version": "2.0", "variables": {protected_var: "some-value"}}
     _yaml.roundtrip_dump(conf, os.path.join(project, "project.conf"))

     element = {
         "kind": "import",
         "sources": [{"kind": "local", "path": "foo.txt"}],
     }
     _yaml.roundtrip_dump(element, os.path.join(project, "target.bst"))

     result = cli.run(project=project, args=["build", "target.bst"])
     result.assert_main_error(ErrorDomain.LOAD, LoadErrorReason.PROTECTED_VARIABLE_REDEFINED)


 @pytest.mark.parametrize("protected_var", PROTECTED_VARIABLES)
 @pytest.mark.datafiles(os.path.join(DATA_DIR, "protected-vars"))
 def test_use_of_protected_var_element_overrides(cli, datafiles, protected_var):
     project = str(datafiles)
     conf = {"name": "test", "min-version": "2.0", "elements": {"manual": {"variables": {protected_var: "some-value"}}}}
     _yaml.roundtrip_dump(conf, os.path.join(project, "project.conf"))

     element = {
         "kind": "manual",
         "sources": [{"kind": "local", "path": "foo.txt"}],
     }
     _yaml.roundtrip_dump(element, os.path.join(project, "target.bst"))

     result = cli.run(project=project, args=["build", "target.bst"])
     result.assert_main_error(ErrorDomain.LOAD, LoadErrorReason.PROTECTED_VARIABLE_REDEFINED)


 @pytest.mark.parametrize("protected_var", PROTECTED_VARIABLES)
 @pytest.mark.datafiles(os.path.join(DATA_DIR, "protected-vars"))
 def test_use_of_protected_var_in_element(cli, datafiles, protected_var):
     project = str(datafiles)
     element = {
         "kind": "import",
         "sources": [{"kind": "local", "path": "foo.txt"}],
         "variables": {protected_var: "some-value"},
     }
     _yaml.roundtrip_dump(element, os.path.join(project, "target.bst"))

     result = cli.run(project=project, args=["build", "target.bst"])
     result.assert_main_error(ErrorDomain.LOAD, LoadErrorReason.PROTECTED_VARIABLE_REDEFINED)


 @pytest.mark.datafiles(os.path.join(DATA_DIR, "shared_variables"))
 def test_variables_are_resolved_in_elements_context(cli, datafiles):
     project = str(datafiles)

     result = cli.run(project=project, args=["build"])
     result.assert_success()

     checkout_dir = os.path.join(project, "checkout")
     for elem in ["one", "two"]:
         result = cli.run(
             project=project,
             args=["artifact", "checkout", "--directory", os.path.join(checkout_dir, elem), "{}.bst".format(elem)],
         )
         result.assert_success()

     assert (os.listdir(os.path.join(checkout_dir, "one")), os.listdir(os.path.join(checkout_dir, "two"))) == (
         ["one.bst"],
         ["two.bst"],
     )


 @pytest.mark.datafiles(os.path.join(DATA_DIR, "public_data_variables"))
 def test_variables_are_resolved_in_public_section(cli, datafiles):
     project = str(datafiles)

     result = cli.run(project=project, args=["show", "--format", "%{public}", "public.bst"])
     result.assert_success()

     output = _yaml.load_data(result.output).strip_node_info()
     expected = {"integration-commands": ["echo expanded"], "test": "expanded"}

     assert {k: v for k, v in output.items() if k in expected} == expected


 @pytest.mark.datafiles(os.path.join(DATA_DIR, "public_data_variables"))
 def test_variables_resolving_errors_in_public_section(cli, datafiles):
     project = str(datafiles)

     result = cli.run(project=project, args=["show", "--format", "%{public}", "public_unresolved.bst"])
     result.assert_main_error(ErrorDomain.LOAD, LoadErrorReason.UNRESOLVED_VARIABLE)


 @pytest.mark.datafiles(os.path.join(DATA_DIR, "partial_context"))
 def test_partial_context_junctions(cli, datafiles):
     project = str(datafiles)

     result = cli.run(project=project, args=["show", "--format", "%{vars}", "test.bst"])
     result.assert_success()
     result_vars = _yaml.load_data(result.output)
     assert result_vars.get_str("eltvar") == "/bar/foo/baz"


 # The notparallel tests use a custom plugin which recreates a situation where
 # a plugin substitutes an environment variable with the protected %{max-jobs}
 # variable, which is set depending on whether the plugin declared notparallel.
 #
 # These are a regression test against issue #1360, where we found variable
 # substitution at the plugin default YAML was buggy when multiple instances
 # were not getting the correct results.
 #
 @pytest.mark.datafiles(os.path.join(DATA_DIR, "notparallel"))
 def test_notparallel(cli, datafiles):
     project = str(datafiles)

     # Test the vars
     result = cli.run(project=project, args=["show", "--format", "%{vars}%{env}", "notparallel.bst"])
     result.assert_success()
     result_vars = _yaml.load_data(result.output)
     assert result_vars.get_str("element-name") == "notparallel.bst"
     assert result_vars.get_str("max-jobs") == "1"
     assert result_vars.get_str("MAKEFLAGS") == "-j1"


 @pytest.mark.datafiles(os.path.join(DATA_DIR, "notparallel"))
 def test_notparallel_twice(cli, datafiles):
     project = str(datafiles)

     #
     # Explicitly configure default max-jobs using user configuration
     #
     cli.configure({"build": {"max-jobs": 2}})

     # Fetch the variables and environment of both elements, where parallel.bst depends on notparallel.bst
     result = cli.run(project=project, args=["show", "--format", "%{vars}%{env}", "parallel.bst"])
     result.assert_success()

     # Split on the empty line, which separates elements in bst show output
     groups = result.output.split("\n\n")
     assert len(groups) >= 2
     notparallel_vars = _yaml.load_data(groups[0])
     parallel_vars = _yaml.load_data(groups[1])

     # Test the first group for the expected notparallel state
     assert notparallel_vars.get_str("element-name") == "notparallel.bst"
     assert notparallel_vars.get_str("max-jobs") == "1"
     assert notparallel_vars.get_str("MAKEFLAGS") == "-j1"

     # Test the second group for the expected !notparallel state
     assert parallel_vars.get_str("element-name") == "parallel.bst"
     assert parallel_vars.get_str("max-jobs") == "2"
     assert parallel_vars.get_str("MAKEFLAGS") == "-j2"
	#
	# 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.
	#

	# Pylint doesn't play well with fixtures and dependency injection from pytest
	# pylint: disable=redefined-outer-name

	import os
	import sys

	import pytest

	from buildstream import _yaml
	from buildstream.exceptions import ErrorDomain, LoadErrorReason
	from buildstream._testing.runcli import cli # pylint: disable=unused-import

	from tests.testutils.site import pip_sample_packages # pylint: disable=unused-import
	from tests.testutils.site import SAMPLE_PACKAGES_SKIP_REASON


	# Project directory
	DATA_DIR = os.path.join(os.path.dirname(os.path.realpath(__file__)), "variables")

	# List of BuildStream protected variables
	PROTECTED_VARIABLES = [("project-name"), ("element-name"), ("max-jobs")]


	def print_warning(msg):
	RED, END = "\033[91m", "\033[0m"
	print(("\n{}{}{}").format(RED, msg, END), file=sys.stderr)


	###############################################################
	# Test proper loading of some default commands from plugins #
	###############################################################
	@pytest.mark.parametrize(
	"target,varname,expected",
	[("autotools.bst", "make-install", 'make -j1 DESTDIR="/buildstream-install" install')],
	)
	@pytest.mark.datafiles(os.path.join(DATA_DIR, "defaults"))
	@pytest.mark.skipif("not pip_sample_packages()", reason=SAMPLE_PACKAGES_SKIP_REASON)
	def test_defaults(cli, datafiles, target, varname, expected):
	project = str(datafiles)
	result = cli.run(project=project, silent=True, args=["show", "--deps", "none", "--format", "%{vars}", target])
	result.assert_success()
	result_vars = _yaml.load_data(result.output)
	assert result_vars.get_str(varname) == expected


	################################################################
	# Test overriding of variables to produce different commands #
	################################################################
	@pytest.mark.parametrize(
	"target,varname,expected",
	[("autotools.bst", "make-install", 'make -j1 DESTDIR="/custom/install/root" install')],
	)
	@pytest.mark.datafiles(os.path.join(DATA_DIR, "overrides"))
	@pytest.mark.skipif("not pip_sample_packages()", reason=SAMPLE_PACKAGES_SKIP_REASON)
	def test_overrides(cli, datafiles, target, varname, expected):
	project = str(datafiles)
	result = cli.run(project=project, silent=True, args=["show", "--deps", "none", "--format", "%{vars}", target])
	result.assert_success()
	result_vars = _yaml.load_data(result.output)
	assert result_vars.get_str(varname) == expected


	@pytest.mark.parametrize(
	"element,provenance",
	[
	# This test makes a reference to an undefined variable in a build command
	("manual.bst", "manual.bst [line 5 column 6]"),
	# This test makes a reference to an undefined variable by another variable,
	# ensuring that we validate variables even when they are unused
	("manual2.bst", "manual2.bst [line 4 column 8]"),
	# This test uses a build command to refer to some variables which ultimately
	# refer to an undefined variable, testing a more complex case.
	("manual3.bst", "manual3.bst [line 6 column 8]"),
	],
	ids=["build-command", "variables", "complex"],
	)
	@pytest.mark.datafiles(os.path.join(DATA_DIR, "missing_variables"))
	def test_undefined(cli, datafiles, element, provenance):
	project = str(datafiles)
	result = cli.run(project=project, silent=True, args=["show", "--deps", "none", "--format", "%{config}", element])
	result.assert_main_error(ErrorDomain.LOAD, LoadErrorReason.UNRESOLVED_VARIABLE)
	assert provenance in result.stderr


	@pytest.mark.parametrize(
	"element,provenances",
	[
	# Test a simple a -> b and b -> a reference
	("simple-cyclic.bst", ["simple-cyclic.bst [line 4 column 5]", "simple-cyclic.bst [line 5 column 5]"]),
	# Test a simple a -> b and b -> a reference with some text involved
	("cyclic.bst", ["cyclic.bst [line 5 column 10]", "cyclic.bst [line 4 column 5]"]),
	# Test an indirect circular dependency
	(
	"indirect-cyclic.bst",
	[
	"indirect-cyclic.bst [line 5 column 5]",
	"indirect-cyclic.bst [line 6 column 5]",
	"indirect-cyclic.bst [line 7 column 5]",
	"indirect-cyclic.bst [line 8 column 5]",
	],
	),
	# Test an indirect circular dependency
	("self-reference.bst", ["self-reference.bst [line 4 column 5]"]),
	],
	ids=["simple", "simple-text", "indirect", "self-reference"],
	)
	@pytest.mark.timeout(30, method="signal")
	@pytest.mark.datafiles(os.path.join(DATA_DIR, "cyclic_variables"))
	def test_circular_reference(cli, datafiles, element, provenances):
	print_warning("Performing cyclic test, if this test times out it will exit the test sequence")
	project = str(datafiles)
	result = cli.run(project=project, silent=True, args=["build", element])
	result.assert_main_error(ErrorDomain.LOAD, LoadErrorReason.CIRCULAR_REFERENCE_VARIABLE)
	for provenance in provenances:
	assert provenance in result.stderr


	# Test that variables which refer to eachother very deeply are
	# still resolved correctly, this ensures that we are not relying
	# on a recursive algorithm limited by stack depth.
	#
	@pytest.mark.parametrize(
	"maxvars",
	[50, 500, 5000],
	)
	@pytest.mark.datafiles(os.path.join(DATA_DIR, "defaults"))
	@pytest.mark.skipif("not pip_sample_packages()", reason=SAMPLE_PACKAGES_SKIP_REASON)
	def test_deep_references(cli, datafiles, maxvars):
	project = str(datafiles)

	# Generate an element with very, very many variables to resolve,
	# each which expand to the value of the previous variable.
	#
	# The bottom variable defines a test value which we check for
	# in the top variable in `bst show` output.
	#
	topvar = "var{}".format(maxvars)
	bottomvar = "var0"
	testvalue = "testvalue {}".format(maxvars)

	# Generate
	variables = {"var{}".format(idx + 1): "%{var" + str(idx) + "}" for idx in range(maxvars)}
	variables[bottomvar] = testvalue
	element = {"kind": "manual", "variables": variables}
	_yaml.roundtrip_dump(element, os.path.join(project, "test.bst"))

	# Run `bst show`
	result = cli.run(project=project, args=["show", "--format", "%{vars}", "test.bst"])
	result.assert_success()

	# Test results
	result_vars = _yaml.load_data(result.output)
	assert result_vars.get_str(topvar) == testvalue


	@pytest.mark.parametrize("protected_var", PROTECTED_VARIABLES)
	@pytest.mark.datafiles(os.path.join(DATA_DIR, "protected-vars"))
	def test_use_of_protected_var_project_conf(cli, datafiles, protected_var):
	project = str(datafiles)
	conf = {"name": "test", "min-version": "2.0", "variables": {protected_var: "some-value"}}
	_yaml.roundtrip_dump(conf, os.path.join(project, "project.conf"))

	element = {
	"kind": "import",
	"sources": [{"kind": "local", "path": "foo.txt"}],
	}
	_yaml.roundtrip_dump(element, os.path.join(project, "target.bst"))

	result = cli.run(project=project, args=["build", "target.bst"])
	result.assert_main_error(ErrorDomain.LOAD, LoadErrorReason.PROTECTED_VARIABLE_REDEFINED)


	@pytest.mark.parametrize("protected_var", PROTECTED_VARIABLES)
	@pytest.mark.datafiles(os.path.join(DATA_DIR, "protected-vars"))
	def test_use_of_protected_var_element_overrides(cli, datafiles, protected_var):
	project = str(datafiles)
	conf = {"name": "test", "min-version": "2.0", "elements": {"manual": {"variables": {protected_var: "some-value"}}}}
	_yaml.roundtrip_dump(conf, os.path.join(project, "project.conf"))

	element = {
	"kind": "manual",
	"sources": [{"kind": "local", "path": "foo.txt"}],
	}
	_yaml.roundtrip_dump(element, os.path.join(project, "target.bst"))

	result = cli.run(project=project, args=["build", "target.bst"])
	result.assert_main_error(ErrorDomain.LOAD, LoadErrorReason.PROTECTED_VARIABLE_REDEFINED)


	@pytest.mark.parametrize("protected_var", PROTECTED_VARIABLES)
	@pytest.mark.datafiles(os.path.join(DATA_DIR, "protected-vars"))
	def test_use_of_protected_var_in_element(cli, datafiles, protected_var):
	project = str(datafiles)
	element = {
	"kind": "import",
	"sources": [{"kind": "local", "path": "foo.txt"}],
	"variables": {protected_var: "some-value"},
	}
	_yaml.roundtrip_dump(element, os.path.join(project, "target.bst"))

	result = cli.run(project=project, args=["build", "target.bst"])
	result.assert_main_error(ErrorDomain.LOAD, LoadErrorReason.PROTECTED_VARIABLE_REDEFINED)


	@pytest.mark.datafiles(os.path.join(DATA_DIR, "shared_variables"))
	def test_variables_are_resolved_in_elements_context(cli, datafiles):
	project = str(datafiles)

	result = cli.run(project=project, args=["build"])
	result.assert_success()

	checkout_dir = os.path.join(project, "checkout")
	for elem in ["one", "two"]:
	result = cli.run(
	project=project,
	args=["artifact", "checkout", "--directory", os.path.join(checkout_dir, elem), "{}.bst".format(elem)],
	)
	result.assert_success()

	assert (os.listdir(os.path.join(checkout_dir, "one")), os.listdir(os.path.join(checkout_dir, "two"))) == (
	["one.bst"],
	["two.bst"],
	)


	@pytest.mark.datafiles(os.path.join(DATA_DIR, "public_data_variables"))
	def test_variables_are_resolved_in_public_section(cli, datafiles):
	project = str(datafiles)

	result = cli.run(project=project, args=["show", "--format", "%{public}", "public.bst"])
	result.assert_success()

	output = _yaml.load_data(result.output).strip_node_info()
	expected = {"integration-commands": ["echo expanded"], "test": "expanded"}

	assert {k: v for k, v in output.items() if k in expected} == expected


	@pytest.mark.datafiles(os.path.join(DATA_DIR, "public_data_variables"))
	def test_variables_resolving_errors_in_public_section(cli, datafiles):
	project = str(datafiles)

	result = cli.run(project=project, args=["show", "--format", "%{public}", "public_unresolved.bst"])
	result.assert_main_error(ErrorDomain.LOAD, LoadErrorReason.UNRESOLVED_VARIABLE)


	@pytest.mark.datafiles(os.path.join(DATA_DIR, "partial_context"))
	def test_partial_context_junctions(cli, datafiles):
	project = str(datafiles)

	result = cli.run(project=project, args=["show", "--format", "%{vars}", "test.bst"])
	result.assert_success()
	result_vars = _yaml.load_data(result.output)
	assert result_vars.get_str("eltvar") == "/bar/foo/baz"


	# The notparallel tests use a custom plugin which recreates a situation where
	# a plugin substitutes an environment variable with the protected %{max-jobs}
	# variable, which is set depending on whether the plugin declared notparallel.
	#
	# These are a regression test against issue #1360, where we found variable
	# substitution at the plugin default YAML was buggy when multiple instances
	# were not getting the correct results.
	#
	@pytest.mark.datafiles(os.path.join(DATA_DIR, "notparallel"))
	def test_notparallel(cli, datafiles):
	project = str(datafiles)

	# Test the vars
	result = cli.run(project=project, args=["show", "--format", "%{vars}%{env}", "notparallel.bst"])
	result.assert_success()
	result_vars = _yaml.load_data(result.output)
	assert result_vars.get_str("element-name") == "notparallel.bst"
	assert result_vars.get_str("max-jobs") == "1"
	assert result_vars.get_str("MAKEFLAGS") == "-j1"


	@pytest.mark.datafiles(os.path.join(DATA_DIR, "notparallel"))
	def test_notparallel_twice(cli, datafiles):
	project = str(datafiles)

	#
	# Explicitly configure default max-jobs using user configuration
	#
	cli.configure({"build": {"max-jobs": 2}})

	# Fetch the variables and environment of both elements, where parallel.bst depends on notparallel.bst
	result = cli.run(project=project, args=["show", "--format", "%{vars}%{env}", "parallel.bst"])
	result.assert_success()

	# Split on the empty line, which separates elements in bst show output
	groups = result.output.split("\n\n")
	assert len(groups) >= 2
	notparallel_vars = _yaml.load_data(groups[0])
	parallel_vars = _yaml.load_data(groups[1])

	# Test the first group for the expected notparallel state
	assert notparallel_vars.get_str("element-name") == "notparallel.bst"
	assert notparallel_vars.get_str("max-jobs") == "1"
	assert notparallel_vars.get_str("MAKEFLAGS") == "-j1"

	# Test the second group for the expected !notparallel state
	assert parallel_vars.get_str("element-name") == "parallel.bst"
	assert parallel_vars.get_str("max-jobs") == "2"
	assert parallel_vars.get_str("MAKEFLAGS") == "-j2"