Always quote program name in Command::spawn on Windows

[ollie27]

CreateProcess will interpret args as part of the binary name if it
doesn't find the binary using just the unquoted name. For example if
foo.exe doesn't exist, Command::new("foo").arg("bar").spawn() will
try to launch foo bar.exe which is clearly not desired.

[retep998]

Alternatively, we could pass the binary name as the first parameter to CreateProcessW instead of having Windows be forced to dig it out of the second parameter. I'd really prefer that approach unless @alexcrichton has some good reason for why we have to do it the way we currently do.

[alexcrichton]

Looks good to me, thanks @ollie27! Would it be possible to add a test for this?

Passing the binary name explicitly sounds fine as well, so it sounds like we should just do both things?

[ollie27]

It looks like using the first parameter behaves very differently:

In the case of a partial name, the function uses the current drive and current directory to complete the specification. The function will not use the search path. This parameter must include the file name extension; no default extension is assumed.

I guess I'll try to write a run-make test for this.

[ollie27]

Right, I've added a run-make test.

[alexcrichton]

@bors: r+

Thanks @ollie27!

[bors]

📌 Commit 02955f5 has been approved by alexcrichton

[retep998]

So I just did a quick test and when I passed a verbatim path as the first parameter to CreateProcessW I was able to specify paths that exceeded MAX_PATH while when I only specified the second parameter it would fail with ERROR_FILENAME_EXCED_RANGE. So even though using the first parameter has fairly different semantics than only using the second parameter, if we ever want to support long paths we'll need to use that first parameter.

[bors]

⌛️ Testing commit 02955f5 with merge 9006db1...

[bors]

☀️ Test successful - status-appveyor, status-travis
Approved by: alexcrichton
Pushing 9006db1 to master...