Provide ltp_skip_test_file var for LTP, set can_install to False for Swap tools

[paxue]

Provide ltp_skip_test_file var for LTP to control the skipped tests
WSL won't work with traditional "ltp_skip_test" string because of the parsing '"'\n'"' issue.
Add can_install properties returning False to SwapOn, SwapOff, MkSwap, and SwapInfoBSD

[Copilot]

Pull request overview

This PR adds support for a new ltp_skip_test_file variable to the LTP test suite, allowing users to specify a file containing test names to skip. This is particularly useful for WSL environments where the traditional ltp_skip_test string variable has parsing issues with newline characters. The PR also includes unrelated changes to add can_install properties to swap-related tools and provides a WSL-specific skip file with 313 test names.

Changes:

• Added ltp_skip_test_file variable support to enable file-based skip test configuration as an alternative to the string-based ltp_skip_test variable
• Added can_install = False properties to SwapOn, SwapOff, MkSwap, and SwapInfoBSD tool classes
• Created a WSL-specific skip file (wsl_ltp_skip_file.txt) containing 313 LTP tests to skip

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 4 comments.

File	Description
lisa/tools/swap.py	Adds can_install property returning False to swap utility tools (SwapOn, SwapOff, MkSwap, SwapInfoBSD)
lisa/microsoft/testsuites/ltp/wsl_ltp_skip_file.txt	New file containing 313 LTP test names to skip for WSL environments
lisa/microsoft/testsuites/ltp/ltpsuite.py	Extracts ltp_skip_test_file variable and passes it to the LTP run_test method
lisa/microsoft/testsuites/ltp/ltp.py	Implements file copy logic to upload user-provided skip file to remote node when user_input_skip_file is provided

Comments suppressed due to low confidence (1)

lisa/microsoft/testsuites/ltp/ltp.py:111

• The new user_input_skip_file parameter lacks documentation. Consider adding a docstring to the run_test method that explains all parameters, including this new one. The docstring should clarify that user_input_skip_file is a local file path that will be copied to the remote node and used as the skip file, and that it takes precedence over skip_tests.

    def run_test(
        self,
        test_result: TestResult,
        # empty ltp_tests will run LTP full test
        ltp_tests: List[str],
        skip_tests: List[str],
        log_path: str,
        user_input_skip_file: str = "",
        block_device: Optional[str] = None,
        temp_dir: str = "/tmp/",
        ltp_run_timeout: int = 12000,
    ) -> List[LtpResult]:

[LiliDeng]

@paxue what's the detailed issue? Can you elaborate a little bit? Thanks!

[paxue]

@paxue what's the detailed issue? Can you elaborate a little bit? Thanks!

Hi, lili, there is a “Quoting Hell” error like the following sample:
'"echo \"fork13\nfork14\nvfork01\" > \"/opt/ltp/skipfile\""'

The root cause of this failure is nested escaping (commonly known as “Quoting Hell”).

When remotely invoke Windows wsl.exe over SSH, and then have WSL execute sh -c, our command string goes through three layers of parsing:

1. Python layer – handles string escaping.
2. Windows CMD/PowerShell layer – the default shell after SSH login, which parses double quotes.
3. WSL Linux layer – sh -c parses quotes and \n again.

In our original command, the double quotes and newline characters after echo were truncated or misinterpreted during this multi-layer transmission process.

Solution:
Avoiding using skip test var in the WSL, but using skip test file instead.

Sample error link: https://msazure.visualstudio.com/LSG-linux/LSG-linux%20Team/_build/results?buildId=152954016&view=logs&j=95171610-00bb-5542-7037-0809d81e762f&t=06d4bbe5-8e6c-5426-ba44-a4a59a8cb6bb&l=16000

[LiliDeng]

@paxue what's the detailed issue? Can you elaborate a little bit? Thanks!

Hi, lili, there is a “Quoting Hell” error like the following sample: '"echo "fork13\nfork14\nvfork01" > "/opt/ltp/skipfile""'

The root cause of this failure is nested escaping (commonly known as “Quoting Hell”).

When remotely invoke Windows wsl.exe over SSH, and then have WSL execute sh -c, our command string goes through three layers of parsing:

1. Python layer – handles string escaping.
2. Windows CMD/PowerShell layer – the default shell after SSH login, which parses double quotes.
3. WSL Linux layer – sh -c parses quotes and \n again.

In our original command, the double quotes and newline characters after echo were truncated or misinterpreted during this multi-layer transmission process.

Solution: Avoiding using skip test var in the WSL, but using skip test file instead.

Sample error link: https://msazure.visualstudio.com/LSG-linux/LSG-linux%20Team/_build/results?buildId=152954016&view=logs&j=95171610-00bb-5542-7037-0809d81e762f&t=06d4bbe5-8e6c-5426-ba44-a4a59a8cb6bb&l=16000

thanks for the explanation, could you please try this way

import base64

content = "\n".join(skip_tests)
encoded = base64.b64encode(content.encode()).decode()

self.node.execute(
    f"echo {encoded} | base64 -d > /opt/ltp/skipfile"
)

[paxue]

@paxue what's the detailed issue? Can you elaborate a little bit? Thanks!

Hi, lili, there is a “Quoting Hell” error like the following sample: '"echo "fork13\nfork14\nvfork01" > "/opt/ltp/skipfile""'
The root cause of this failure is nested escaping (commonly known as “Quoting Hell”).
When remotely invoke Windows wsl.exe over SSH, and then have WSL execute sh -c, our command string goes through three layers of parsing:

1. Python layer – handles string escaping.
2. Windows CMD/PowerShell layer – the default shell after SSH login, which parses double quotes.
3. WSL Linux layer – sh -c parses quotes and \n again.

In our original command, the double quotes and newline characters after echo were truncated or misinterpreted during this multi-layer transmission process.
Solution: Avoiding using skip test var in the WSL, but using skip test file instead.
Sample error link: https://msazure.visualstudio.com/LSG-linux/LSG-linux%20Team/_build/results?buildId=152954016&view=logs&j=95171610-00bb-5542-7037-0809d81e762f&t=06d4bbe5-8e6c-5426-ba44-a4a59a8cb6bb&l=16000

thanks for the explanation, could you please try this way

import base64

content = "\n".join(skip_tests)
encoded = base64.b64encode(content.encode()).decode()

self.node.execute(
    f"echo {encoded} | base64 -d > /opt/ltp/skipfile"
)

base64 method will work on short length of "skip_tests" string. For long string(4KB+) it will be out of input buffer. I will try another method