Apple - Problem with empty spaces when executing shell commands in AppleScript

Try:

set pathwithSpaces to "/Users/John/Desktop/This is a test.docx"
do shell script "rm -r " & quoted form of pathwithSpaces

You have to double the backslashes and also escape the other spaces:

do shell script "rm -r ~/Library/Application\\ Support/Google/Chrome/Default/Pepper\\ Data/Shockwave\\ Flash"

or escape the path some other way:

do shell script "rm -r ~/'Library/Application Support/Google/Chrome/Default/Pepper Data/Shockwave Flash'"

quoted form of replaces ' with '\'' and surrounds the string with single quotes, so it doesn't work with paths that start with ~/.

do shell script "open -n /Applications/App\\ Store.app"

Handle the space with \\.

For example replace App Store.app with App\\ Store.app.