code: func (f *file) lintBlankImports() {
  	// In package main and in tests, we don't complain about blank imports.
  	if f.pkg.main || f.isTest() {
  		return
  	}
  
  	// The first element of each contiguous group of blank imports should have
  	// an explanatory comment of some kind.
  	for i, imp := range f.f.Imports {
  		pos := f.fset.Position(imp.Pos())
  
  		if !isBlank(imp.Name) {
  			continue // Ignore non-blank imports.
  		}
  		if i > 0 {
  			prev := f.f.Imports[i-1]
  			prevPos := f.fset.Position(prev.Pos())
  			if isBlank(prev.Name) && prevPos.Line+1 == pos.Line {
  				continue // A subsequent blank in a group.
  			}
  		}
  
  		// This is the first blank import of a group.
  		if imp.Doc == nil && imp.Comment == nil {
  			ref := ""
  			f.errorf(imp, 1, link(ref), category("imports"), "a blank import should be only in a main or test package, or have a comment justifying it")
  		}
  	}
  }
docs: // lintBlankImports complains if a non-main package has blank imports that are
  // not documented.