kconfig: test: add Kconfig macro language tests

# SPDX-License-Identifier: GPL-2.0

# 'info' prints the argument to stdout.

$(info,hello world 0)

# 'warning-if', if the first argument is y, sends the second argument to stderr,

# and the message is prefixed with the current file name and line number.

$(warning-if,y,hello world 1)

# 'error-if' is similar, but it terminates the parsing immediately.

# The following is just no-op since the first argument is not y.

$(error-if,n,this should not be printed)

# Shorthand

warning = $(warning-if,y,$(1))

# 'shell' executes a command, and returns its stdout.

$(warning,$(shell,echo hello world 3))

# Every newline in the output is replaced with a space,

# but any trailing newlines are deleted.

$(warning,$(shell,printf 'hello\nworld\n\n4\n\n\n'))

# 'filename' is expanded to the currently parsed file name,

# 'lineno' to the line number.

$(warning,filename=$(filename))

$(warning,lineno=$(lineno))

# SPDX-License-Identifier: GPL-2.0

"""

Built-in function tests.

"""

def test(conf):

    assert conf.oldaskconfig() == 0

    assert conf.stdout_contains('expected_stdout')

    assert conf.stderr_matches('expected_stderr')

Kconfig:8: hello world 1

Kconfig:18: hello world 3

Kconfig:22: hello world  4

Kconfig:26: filename=Kconfig

Kconfig:27: lineno=27

hello world 0

# SPDX-License-Identifier: GPL-2.0

X = $(Y)

Y = $(X)

$(info $(X))