How to make svn diff show remote changes?

For Example, when I type

svn st --show-updates 

I get

    *   1648648   project/file1

so I know that file1 has changed.

I don't want to update just 开发者_StackOverflow中文版find out what has changed. When I type

svn diff project/file1

it shows nothing because the file has no local changes.

How to make svn diff show remote changes?

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simply ask svn to make the diff with the HEAD revision :

svn diff -r HEAD project/file1

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Most correct version of diff between unmodified WC and updated repo is expanded answer of Cédric

svn diff -r BASE -r HEAD project/file1