Powershell Docker Command Doesn’t Work Like Bat File

First, the obligatory warning: Unless you have a command line stored as a single string somewhere and you either fully control or trust the content of the string, Invoke-Expression should generally be avoided.

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You’re seeing an inconsistency in how PowerShell treats compound tokens composed of directly concatenated quoted and unquoted parts.

Specifically, argument "C:\Test Folder With Blanks":/zzz is unexpectedly broken in two, i.e passed as two arguments.

The workaround is to quote the entire argument, i.e.
"C:\Test Folder With Blanks:/zzz"

^{Note: I’m assuming that docker doesn’t actually require partial quoting in its arguments, which it shouldn’t; however, there are high-profile CLIs on Windows that do, notably msiexec.}

Alternatively, use an expression enclosed in (...) to compose your string; e.g.
("C:\Test Folder With Blanks" + ':/zzz')

^{There’s no good reason to do so in this case, but it could be helpful if you need string interpolation in one part of your string ("..."), but not in another ('...').}

General caveats:

• Compared to cmd.exe and also POSIX-compatible shells such as bash, PowerShell has several additional metacharacters, notably @ (at the start of a token), { / }, and ;. Therefore, you cannot always expect command lines written for these shells to work as-is in PowerShell.

• As of PowerShell 7.2.2, passing arguments to external programs (such as docker) is fundamentally broken with respect to arguments that have embedded " characters and empty-string arguments – see this answer.

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The general pattern of the inconsistency, as of PowerShell 7.2.2, is as follows:

If an argument:

• starts with a quoted token – whether single- ('...') or double-quoted ("...") –
• and has additional characters directly following the closing quote,

the first such character starts a separate argument.

E.g. "foo":bar / "foo"=bar / "foo"'bar' are passed as separate arguments foo and :bar / foo and =bar / foo and bar, respectively.

In other words:

• You cannot compose a single string argument from a mix of quoted and unquoted / differently quoted tokens if the first token is quoted.

• Conversely, it does work if the first token is unquoted, including an unquoted simple variable reference such as $HOME.

# OK: First token is unquoted.
PS> cmd /c echo foo"bar"'baz'last
foobarbazlast

# !! BROKEN: First token is quoted.
# !!         Because each successive token is quoted too, 
# !!         each becomes its own argument.
PS> cmd /c echo 'foo'"bar"'baz'last
foo bar baz last

GitHub issue #6467 discusses this inconsistency; however, it has been closed, because the behavior is – surprisingly – considered by design.

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This does not happen if the first token is unquoted; however, there are related bugs that start with unquoted tokens that similarly break arguments in two, related to their looking like named arguments to PowerShell (which is a PowerShell concept that doesn’t apply when calling external programs):

• GitHub issue #11646: an argument such as -foo=1,2 breaks parsing.

• GitHub issue #6291: an argument such as -foo=bar.baz is broken in two at the (first) .