keep_var_for_in: {
    options = {
        hoist_vars: true,
        unused: true
    };
    input: {
        (function(obj){
            var foo = 5;
            for (var i in obj)
                return foo;
        })();
    }
    expect: {
        (function(obj){
            var i, foo = 5;
            for (i in obj)
                return foo;
        })();
    }
}
<tr>
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</select> <input type='submit' value='switch'/></form></td></tr>
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<table class='tabs'><tr><td>
<a href='/guix/about/'>about</a><a href='/guix/'>summary</a><a href='/guix/refs/?id=d7f017d5ff5b045d8e4e18ccf4ede3a10da01906'>refs</a><a class='active' href='/guix/log/tests/accounts.scm'>log</a><a href='/guix/tree/tests/accounts.scm?id=d7f017d5ff5b045d8e4e18ccf4ede3a10da01906'>tree</a><a href='/guix/commit/tests/accounts.scm?id=d7f017d5ff5b045d8e4e18ccf4ede3a10da01906'>commit</a><a href='/guix/diff/tests/accounts.scm?id=d7f017d5ff5b045d8e4e18ccf4ede3a10da01906'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/tests/accounts.scm'>
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<option value='grep'>log msg</option>
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</select>
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</form>
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<div class='path'>path: <a href='/guix/log/?id=d7f017d5ff5b045d8e4e18ccf4ede3a10da01906'>root</a>/<a href='/guix/log/tests?id=d7f017d5ff5b045d8e4e18ccf4ede3a10da01906'>tests</a>/<a href='/guix/log/tests/accounts.scm?id=d7f017d5ff5b045d8e4e18ccf4ede3a10da01906'>accounts.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/tests/accounts.scm?id=d7f017d5ff5b045d8e4e18ccf4ede3a10da01906&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>