local helpers = require('test.functional.helpers')(after_each)
local clear = helpers.clear
local eq = helpers.eq
local command = helpers.command
local meths = helpers.meths
local eval = helpers.eval
local exc_exec = helpers.exc_exec
local pcall_err = helpers.pcall_err
local funcs = helpers.funcs
local NIL = helpers.NIL
local source = helpers.source

describe('string() function', function()
  before_each(clear)

  describe('used to represent floating-point values', function()
    it('dumps NaN values', function()
      eq('str2float(\'nan\')', eval('string(str2float(\'nan\'))'))
    end)

    it('dumps infinite values', function()
      eq('str2float(\'inf\')', eval('string(str2float(\'inf\'))'))
      eq('-str2float(\'inf\')', eval('string(str2float(\'-inf\'))'))
    end)

    it('dumps regular values', function()
      eq('1.5', funcs.string(1.5))
      eq('1.56e-20', funcs.string(1.56000e-020))
      eq('0.0', eval('string(0.0)'))
    end)

    it('dumps special v: values', function()
      eq('v:true', eval('string(v:true)'))
      eq('v:false', eval('string(v:false)'))
      eq('v:null', eval('string(v:null)'))
      eq('v:true', funcs.string(true))
      eq('v:false', funcs.string(false))
      eq('v:null', funcs.string(NIL))
    end)

    it('dumps values with at most six digits after the decimal point',
    function()
      eq('1.234568e-20', funcs.string(1.23456789123456789123456789e-020))
      eq('1.234568', funcs.string(1.23456789123456789123456789))
    end)

    it('dumps values with at most seven digits before the decimal point',
    function()
      eq('1234567.891235', funcs.string(1234567.89123456789123456789))
      eq('1.234568e7', funcs.string(12345678.9123456789123456789))
    end)

    it('dumps negative values', function()
      eq('-1.5', funcs.string(-1.5))
      eq('-1.56e-20', funcs.string(-1.56000e-020))
      eq('-1.234568e-20', funcs.string(-1.23456789123456789123456789e-020))
      eq('-1.234568', funcs.string(-1.23456789123456789123456789))
      eq('-1234567.891235', funcs.string(-1234567.89123456789123456789))
      eq('-1.234568e7', funcs.string(-12345678.9123456789123456789))
    end)
  end)

  describe('used to represent numbers', function()
    it('dumps regular values', function()
      eq('0', funcs.string(0))
      eq('-1', funcs.string(-1))
      eq('1', funcs.string(1))
    end)

    it('dumps large values', function()
      eq('2147483647', funcs.string(2^31-1))
      eq('-2147483648', funcs.string(-2^31))
    end)
  end)

  describe('used to represent strings', function()
    it('dumps regular strings', function()
      eq('\'test\'', funcs.string('test'))
    end)

    it('dumps empty strings', function()
      eq('\'\'', funcs.string(''))
    end)

    it('dumps strings with \' inside', function()
      eq('\'\'\'\'\'\'\'\'', funcs.string('\'\'\''))
      eq('\'a\'\'b\'\'\'\'\'', funcs.string('a\'b\'\''))
      eq('\'\'\'b\'\'\'\'d\'', funcs.string('\'b\'\'d'))
      eq('\'a\'\'b\'\'c\'\'d\'', funcs.string('a\'b\'c\'d'))
    end)

    it('dumps NULL strings', function()
      eq('\'\'', eval('string($XXX_UNEXISTENT_VAR_XXX)'))
    end)

    it('dumps NULL lists', function()
      eq('[]', eval('string(v:_null_list)'))
    end)

    it('dumps NULL dictionaries', function()
      eq('{}', eval('string(v:_null_dict)'))
    end)
  end)

  describe('used to represent funcrefs', function()
    before_each(function()
      source([[
        function Test1()
        endfunction

        function s:Test2() dict
        endfunction

        function g:Test3() dict
        endfunction

        let g:Test2_f = function('s:Test2')
      ]])
    end)

    it('dumps references to built-in functions', function()
      eq('function(\'function\')', eval('string(function("function"))'))
    end)

    it('dumps references to user functions', function()
      eq('function(\'Test1\')', eval('string(function("Test1"))'))
      eq('function(\'g:Test3\')', eval('string(function("g:Test3"))'))
    end)

    it('dumps references to script functions', function()
      eq('function(\'<SNR>1_Test2\')', eval('string(Test2_f)'))
    end)

    it('dumps partials with self referencing a partial', function()
      source([[
        function TestDict() dict
        endfunction
        let d = {}
        let TestDictRef = function('TestDict', d)
        let d.tdr = TestDictRef
      ]])
      eq("Vim(echo):E724: unable to correctly dump variable with self-referencing container",
         pcall_err(command, 'echo string(d.tdr)'))
    end)

    it('dumps automatically created partials', function()
      eq('function(\'<SNR>1_Test2\', {\'f\': function(\'<SNR>1_Test2\')})',
         eval('string({"f": Test2_f}.f)'))
      eq('function(\'<SNR>1_Test2\', [1], {\'f\': function(\'<SNR>1_Test2\', [1])})',
         eval('string({"f": function(Test2_f, [1])}.f)'))
    end)

    it('dumps manually created partials', function()
      eq('function(\'Test3\', [1, 2], {})',
         eval('string(function("Test3", [1, 2], {}))'))
      eq('function(\'Test3\', {})',
         eval('string(function("Test3", {}))'))
      eq('function(\'Test3\', [1, 2])',
         eval('string(function("Test3", [1, 2]))'))
    end)

    it('does not crash or halt when dumping partials with reference cycles in self',
    function()
      meths.set_var('d', {v=true})
      eq([[Vim(echo):E724: unable to correctly dump variable with self-referencing container]],
        pcall_err(command, 'echo string(extend(extend(g:d, {"f": g:Test2_f}), {"p": g:d.f}))'))
    end)

    it('does not show errors when dumping partials referencing the same dictionary',
    function()
      command('let d = {}')
      -- Regression for “eval/typval_encode: Dump empty dictionary before
      -- checking for refcycle”, results in error.
      eq('[function(\'tr\', {}), function(\'tr\', {})]', eval('string([function("tr", d), function("tr", d)])'))
      -- Regression for “eval: Work with reference cycles in partials (self)
      -- properly”, results in crash.
      eval('extend(d, {"a": 1})')
      eq('[function(\'tr\', {\'a\': 1}), function(\'tr\', {\'a\': 1})]', eval('string([function("tr", d), function("tr", d)])'))
    end)

    it('does not crash or halt when dumping partials with reference cycles in arguments',
    function()
      meths.set_var('l', {})
      eval('add(l, l)')
      -- Regression: the below line used to crash (add returns original list and
      -- there was error in dumping partials). Tested explicitly in
      -- test/unit/api/private_helpers_spec.lua.
      eval('add(l, function("Test1", l))')
      eq([=[Vim(echo):E724: unable to correctly dump variable with self-referencing container]=],
        pcall_err(command, 'echo string(function("Test1", l))'))
    end)

    it('does not crash or halt when dumping partials with reference cycles in self and arguments',
    function()
      meths.set_var('d', {v=true})
      meths.set_var('l', {})
      eval('add(l, l)')
      eval('add(l, function("Test1", l))')
      eval('add(l, function("Test1", d))')
      eq([=[Vim(echo):E724: unable to correctly dump variable with self-referencing container]=],
        pcall_err(command, 'echo string(extend(extend(g:d, {"f": g:Test2_f}), {"p": function(g:d.f, l)}))'))
    end)
  end)

  describe('used to represent lists', function()
    it('dumps empty list', function()
      eq('[]', funcs.string({}))
    end)

    it('dumps nested lists', function()
      eq('[[[[[]]]]]', funcs.string({{{{{}}}}}))
    end)

    it('dumps nested non-empty lists', function()
      eq('[1, [[3, [[5], 4]], 2]]', funcs.string({1, {{3, {{5}, 4}}, 2}}))
    end)

    it('errors when dumping recursive lists', function()
      meths.set_var('l', {})
      eval('add(l, l)')
      eq('Vim(echo):E724: unable to correctly dump variable with self-referencing container',
         exc_exec('echo string(l)'))
    end)

    it('dumps recursive lists despite the error', function()
      meths.set_var('l', {})
      eval('add(l, l)')
      eq('Vim(echo):E724: unable to correctly dump variable with self-referencing container',
         pcall_err(command, 'echo string(l)'))
      eq('Vim(echo):E724: unable to correctly dump variable with self-referencing container',
         pcall_err(command, 'echo string([l])'))
    end)
  end)

  describe('used to represent dictionaries', function()
    it('dumps empty dictionary', function()
      eq('{}', eval('string({})'))
    end)

    it('dumps list with two same empty dictionaries, also in partials', function()
      command('let d = {}')
      eq('[{}, {}]', eval('string([d, d])'))
      eq('[function(\'tr\', {}), {}]', eval('string([function("tr", d), d])'))
      eq('[{}, function(\'tr\', {})]', eval('string([d, function("tr", d)])'))
    end)

    it('dumps non-empty dictionary', function()
      eq('{\'t\'\'est\': 1}', funcs.string({['t\'est']=1}))
    end)

    it('errors when dumping recursive dictionaries', function()
      meths.set_var('d', {d=1})
      eval('extend(d, {"d": d})')
      eq('Vim(echo):E724: unable to correctly dump variable with self-referencing container',
         exc_exec('echo string(d)'))
    end)

    it('dumps recursive dictionaries despite the error', function()
      meths.set_var('d', {d=1})
      eval('extend(d, {"d": d})')
      eq('Vim(echo):E724: unable to correctly dump variable with self-referencing container',
         pcall_err(command, 'echo string(d)'))
      eq('Vim(echo):E724: unable to correctly dump variable with self-referencing container',
         pcall_err(command, 'echo string({"out": d})'))
    end)
  end)
end)
