See All Log Changes Ignoring Whitespace Changes in SVN:
svn diff -x -w FILE
See differences between the current working version of FILE and the checked-in version, ignoring all white space changes.
The -x option allows you to pass options to the underlying diff command.
See All Log Changes Ignoring Whitespace and End-of-line Changes in SVN:
svn diff -x "-w --ignore-eof" FILE
See differences between the current working version of FILE and the checked-in version, ignoring all white space and end-of-line type changes (e.g. Unix, Windows, Mac.).
The -x option allows you to pass options to the underlying diff command.