Quote bat script command line

[ChrisDenton]

Fixes #91991

CreateProcessW should only be used to run exe files but it does have some (undocumented) special handling for files with .bat and .cmd extensions. Essentially those magic extensions will cause the parameters to be automatically rewritten. Example pseudo Rust code (note that CreateProcess starts with an optional application name followed by the application arguments):

// These arguments...
CreateProcess(None, @"foo.bat "hello world""@, ...);
// ...are rewritten as
CreateProcess(Some(r"C:\Windows\System32\cmd.exe"), @""foo.bat "hello world"""@, ...);

However, when setting the first parameter (the application name) as we now do, it will omit the extra level of quotes around the arguments:

// These arguments...
CreateProcess(Some("foo.bat"), @"foo.bat "hello world""@, ...);
// ...are rewritten as
CreateProcess(Some(r"C:\Windows\System32\cmd.exe"), @"foo.bat "hello world""@, ...);

This means the arguments won't be passed to the script as intended.

Note that running batch files this way is undocumented but people have relied on this so we probably shouldn't break it.

[rust-highfive]

r? @dtolnay

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[dtolnay]

Thanks!

[dtolnay]

@bors r+

[bors]

📌 Commit de764a7 has been approved by dtolnay

[Mark-Simulacrum]

beta-nominated due to https://rust-lang.zulipchat.com/#narrow/stream/219381-t-libs/topic/Last.20minute.20backport.3F