neovim/test/functional/eval/special_vars_spec.lua

local helpers = require('test.functional.helpers')
local exc_exec = helpers.exc_exec
local execute = helpers.execute
local meths = helpers.meths
local funcs = helpers.funcs
local meths = helpers.meths
local clear = helpers.clear
local eval = helpers.eval
local eq = helpers.eq

describe('Special values', function()
  before_each(clear)

  it('do not cause error when freed', function()
    execute([[
      function Test()
        try
          return v:true
        finally
          return 'something else'
        endtry
      endfunction
    ]])
    eq(0, exc_exec('call Test()'))
  end)

  it('work with empty()', function()
    eq(0, funcs.empty(true))
    eq(1, funcs.empty(false))
    eq(1, eval('empty(v:null)'))
  end)

  it('can be stringified and eval’ed back', function()
    eq(true, funcs.eval(funcs.string(true)))
    eq(false, funcs.eval(funcs.string(false)))
    eq(nil, eval('eval(string(v:null))'))
  end)

  it('work with is/isnot properly', function()
    eq(1, eval('v:null is v:null'))
    eq(0, eval('v:null is v:true'))
    eq(0, eval('v:null is v:false'))
    eq(1, eval('v:true is v:true'))
    eq(0, eval('v:true is v:false'))
    eq(1, eval('v:false is v:false'))

    eq(0, eval('v:null  is 0'))
    eq(0, eval('v:true  is 0'))
    eq(0, eval('v:false is 0'))

    eq(0, eval('v:null  is 1'))
    eq(0, eval('v:true  is 1'))
    eq(0, eval('v:false is 1'))

    eq(0, eval('v:null  is ""'))
    eq(0, eval('v:true  is ""'))
    eq(0, eval('v:false is ""'))

    eq(0, eval('v:null  is "null"'))
    eq(0, eval('v:true  is "true"'))
    eq(0, eval('v:false is "false"'))

    eq(0, eval('v:null  is []'))
    eq(0, eval('v:true  is []'))
    eq(0, eval('v:false is []'))

    eq(0, eval('v:null isnot v:null'))
    eq(1, eval('v:null isnot v:true'))
    eq(1, eval('v:null isnot v:false'))
    eq(0, eval('v:true isnot v:true'))
    eq(1, eval('v:true isnot v:false'))
    eq(0, eval('v:false isnot v:false'))

    eq(1, eval('v:null  isnot 0'))
    eq(1, eval('v:true  isnot 0'))
    eq(1, eval('v:false isnot 0'))

    eq(1, eval('v:null  isnot 1'))
    eq(1, eval('v:true  isnot 1'))
    eq(1, eval('v:false isnot 1'))

    eq(1, eval('v:null  isnot ""'))
    eq(1, eval('v:true  isnot ""'))
    eq(1, eval('v:false isnot ""'))

    eq(1, eval('v:null  isnot "null"'))
    eq(1, eval('v:true  isnot "true"'))
    eq(1, eval('v:false isnot "false"'))

    eq(1, eval('v:null  isnot []'))
    eq(1, eval('v:true  isnot []'))
    eq(1, eval('v:false isnot []'))
  end)

  it('work with +/-/* properly', function()
    eq(1, eval('0 + v:true'))
    eq(0, eval('0 + v:null'))
    eq(0, eval('0 + v:false'))

    eq(-1, eval('0 - v:true'))
    eq( 0, eval('0 - v:null'))
    eq( 0, eval('0 - v:false'))

    eq(1, eval('1 * v:true'))
    eq(0, eval('1 * v:null'))
    eq(0, eval('1 * v:false'))
  end)

  it('does not work with +=/-=/.=', function()
    meths.set_var('true', true)
    meths.set_var('false', false)
    execute('let null = v:null')

    eq('Vim(let):E734: Wrong variable type for +=', exc_exec('let true  += 1'))
    eq('Vim(let):E734: Wrong variable type for +=', exc_exec('let false += 1'))
    eq('Vim(let):E734: Wrong variable type for +=', exc_exec('let null  += 1'))

    eq('Vim(let):E734: Wrong variable type for -=', exc_exec('let true  -= 1'))
    eq('Vim(let):E734: Wrong variable type for -=', exc_exec('let false -= 1'))
    eq('Vim(let):E734: Wrong variable type for -=', exc_exec('let null  -= 1'))

    eq('Vim(let):E734: Wrong variable type for .=', exc_exec('let true  .= 1'))
    eq('Vim(let):E734: Wrong variable type for .=', exc_exec('let false .= 1'))
    eq('Vim(let):E734: Wrong variable type for .=', exc_exec('let null  .= 1'))
  end)

  it('work with . (concat) properly', function()
    eq("true", eval('"" . v:true'))
    eq("null", eval('"" . v:null'))
    eq("false", eval('"" . v:false'))
  end)

  it('work with type()', function()
    eq(6, funcs.type(true))
    eq(6, funcs.type(false))
    eq(7, eval('type(v:null)'))
  end)

  it('work with copy() and deepcopy()', function()
    eq(true, funcs.deepcopy(true))
    eq(false, funcs.deepcopy(false))
    eq(nil, eval('deepcopy(v:null)'))

    eq(true, funcs.copy(true))
    eq(false, funcs.copy(false))
    eq(nil, eval('copy(v:null)'))
  end)

  it('fails in index', function()
    eq('Vim(echo):E15: Cannot index a special value', exc_exec('echo v:true[0]'))
    eq('Vim(echo):E15: Cannot index a special value', exc_exec('echo v:false[0]'))
    eq('Vim(echo):E15: Cannot index a special value', exc_exec('echo v:null[0]'))
  end)

  it('is accepted by assert_true and assert_false', function()
    funcs.assert_false(false)
    funcs.assert_false(true)
    eval('assert_false(v:null)')

    funcs.assert_true(false)
    funcs.assert_true(true)
    eval('assert_true(v:null)')

    eq({
      'Expected False but got v:true',
      'Expected False but got v:null',
      'Expected True but got v:false',
      'Expected True but got v:null',
    }, meths.get_vvar('errors'))
  end)
end)