Struct utf8_command::Utf8Output

source ·

pub struct Utf8Output {
    pub status: ExitStatus,
    pub stdout: String,
    pub stderr: String,
}

Expand description

A UTF-8-decoded variant of std::process::Output (as produced by std::process::Command::output).

Construct Utf8Output from Output via the TryInto or TryFrom traits:

let output: Utf8Output = Command::new("echo")
    .arg("puppy")
    .output()
    .unwrap()
    .try_into()
    .unwrap();
assert_eq!(
    output,
    Utf8Output {
        status: ExitStatus::default(),
        stdout: String::from("puppy\n"),
        stderr: String::from(""),
    },
);

Error messages will include information about the stream that failed to decode, as well as the output (with invalid UTF-8 bytes replaced with U+FFFD REPLACEMENT CHARACTER):

let invalid = Output {
    status: ExitStatus::default(),
    stdout: Vec::from(b"\xc3\x28"), // Invalid 2-byte sequence.
    stderr: Vec::from(b""),
};

let err: Result<Utf8Output, Error> = invalid.try_into();
assert_eq!(
    err.unwrap_err().to_string(),
    "Stdout contained invalid utf-8 sequence of 1 bytes from index 0: \"�(\""
);

If there’s a lot of output (currently, more than 1024 bytes), only the portion around the decode error will be shown:

let mut stdout = vec![];
for _ in 0..300 {
    stdout.extend(b"puppy ");
}
// Add an invalid byte:
stdout[690] = 0xc0;

let invalid = Output {
    status: ExitStatus::default(),
    stdout,
    stderr: Vec::from(b""),
};

let err: Result<Utf8Output, Error> = invalid.try_into();
assert_eq!(
    err.unwrap_err().to_string(),
    "Stdout contained invalid utf-8 sequence of 1 bytes from index 690: \
    [178 bytes] \"y puppy puppy puppy puppy puppy puppy puppy puppy puppy \
    puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy \
    puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy \
    puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy \
    puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy \
    puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy \
    puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy \
    puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy �uppy \
    puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy \
    puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy \
    puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy \
    puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy \
    puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy \
    puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy \
    puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy puppy \
    puppy puppy puppy puppy puppy puppy puppy pu\" [598 bytes]"
);