jashkenas--coffeescript/test/comments.coffee

# Comments
# --------

# * Single-Line Comments
# * Block Comments

# Note: awkward spacing seen in some tests is likely intentional.

test "comments in objects", ->
  obj1 = {
  # comment
    # comment
      # comment
    one: 1
  # comment
    two: 2
      # comment
  }

  ok Object::hasOwnProperty.call(obj1,'one')
  eq obj1.one, 1
  ok Object::hasOwnProperty.call(obj1,'two')
  eq obj1.two, 2

test "comments in YAML-style objects", ->
  obj2 =
  # comment
    # comment
      # comment
    three: 3
  # comment
    four: 4
      # comment

  ok Object::hasOwnProperty.call(obj2,'three')
  eq obj2.three, 3
  ok Object::hasOwnProperty.call(obj2,'four')
  eq obj2.four, 4

test "comments following operators that continue lines", ->
  sum =
    1 +
    1 + # comment
    1
  eq 3, sum

test "comments in functions", ->
  fn = ->
  # comment
    false
    false   # comment
    false
    # comment

  # comment before return
    true

  ok fn()

  fn2 = -> #comment
    fn()
    # comment after return

  ok fn2()

test "trailing comment before an outdent", ->
  nonce = {}
  fn3 = ->
    if true
      undefined # comment
    nonce

  eq nonce, fn3()

test "comments in a switch", ->
  nonce = {}
  result = switch nonce #comment
    # comment
    when false then undefined
    # comment
    when null #comment
      undefined
    else nonce # comment

  eq nonce, result

test "comment with conditional statements", ->
  nonce = {}
  result = if false # comment
    undefined
  #comment
  else # comment
    nonce
    # comment
  eq nonce, result

test "spaced comments with conditional statements", ->
  nonce = {}
  result = if false
    undefined

  # comment
  else if false
    undefined

  # comment
  else
    nonce

  eq nonce, result


# Block Comments

###
  This is a here-comment.
  Kind of like a heredoc.
###

test "block comments in objects", ->
  a = {}
  b = {}
  obj = {
    a: a
    ###
    block comment in object
    ###
    b: b
  }

  eq a, obj.a
  eq b, obj.b

test "block comments in YAML-style", ->
  a = {}
  b = {}
  obj =
    a: a
    ###
    block comment in YAML-style
    ###
    b: b

  eq a, obj.a
  eq b, obj.b


test "block comments in functions", ->
  nonce = {}

  fn1 = ->
    true
    ###
    false
    ###

  ok fn1()

  fn2 = ->
    ###
    block comment in function 1
    ###
    nonce

  eq nonce, fn2()

  fn3 = ->
    nonce
  ###
  block comment in function 2
  ###

  eq nonce, fn3()

  fn4 = ->
    one = ->
      ###
        block comment in function 3
      ###
      two = ->
        three = ->
          nonce

  eq nonce, fn4()()()()

test "block comments inside class bodies", ->
  class A
    a: ->

    ###
    Comment in class body 1
    ###
    b: ->

  ok A.prototype.b instanceof Function

  class B
    ###
    Comment in class body 2
    ###
    a: ->
    b: ->

  ok B.prototype.a instanceof Function

test "#2037: herecomments shouldn't imply line terminators", ->
  do (-> ### ###yes; fail)

test "#2916: block comment before implicit call with implicit object", ->
  fn = (obj) -> ok obj.a
  ### ###
  fn
    a: yes

test "#3132: Format single-line block comment nicely", ->
  eqJS """
  ### Single-line block comment without additional space here => ###""",
  """
  /* Single-line block comment without additional space here => */
  """

test "#3132: Format multiline block comment nicely", ->
  eqJS """
  ###
  # Multiline
  # block
  # comment
  ###""",
  """
  /*
   * Multiline
   * block
   * comment
   */
  """

test "#3132: Format simple block comment nicely", ->
  eqJS """
  ###
  No
  Preceding hash
  ###""",
  """
  /*
  No
  Preceding hash
  */
  """


test "#3132: Format indented block-comment nicely", ->
  eqJS """
  fn = ->
    ###
    # Indented
    Multiline
    ###
    1""",
  """
  var fn;

  fn = function() {
    /*
     * Indented
    Multiline
     */
    return 1;
  };
  """

# Although adequately working, block comment-placement is not yet perfect.
# (Considering a case where multiple variables have been declared …)
test "#3132: Format jsdoc-style block-comment nicely", ->
  eqJS """
  ###*
  # Multiline for jsdoc-"@doctags"
  #
  # @type {Function}
  ###
  fn = () -> 1
  """,
  """
  /**
   * Multiline for jsdoc-"@doctags"
   *
   * @type {Function}
   */
  var fn;

  fn = function() {
    return 1;
  };"""

# Although adequately working, block comment-placement is not yet perfect.
# (Considering a case where multiple variables have been declared …)
test "#3132: Format hand-made (raw) jsdoc-style block-comment nicely", ->
  eqJS """
  ###*
   * Multiline for jsdoc-"@doctags"
   *
   * @type {Function}
  ###
  fn = () -> 1
  """,
  """
  /**
   * Multiline for jsdoc-"@doctags"
   *
   * @type {Function}
   */
  var fn;

  fn = function() {
    return 1;
  };"""

# Although adequately working, block comment-placement is not yet perfect.
# (Considering a case where multiple variables have been declared …)
test "#3132: Place block-comments nicely", ->
  eqJS """
  ###*
  # A dummy class definition
  #
  # @class
  ###
  class DummyClass

    ###*
    # @constructor
    ###
    constructor: ->

    ###*
    # Singleton reference
    #
    # @type {DummyClass}
    ###
    @instance = new DummyClass()

  """,
  """
  /**
   * A dummy class definition
   *
   * @class
   */
  var DummyClass;

  DummyClass = (function() {
    class DummyClass {
      /**
       * @constructor
       */
      constructor() {}

    };

    /**
     * Singleton reference
     *
     * @type {DummyClass}
     */
    DummyClass.instance = new DummyClass();

    return DummyClass;

  }).call(this);"""

test "#3638: Demand a whitespace after # symbol", ->
  eqJS """
  ###
  #No
  #whitespace
  ###""",
  """
  /*
  #No
  #whitespace
   */"""


test "#3761: Multiline comment at end of an object", ->
  anObject =
    x: 3
    ###
    #Comment
    ###

  ok anObject.x is 3

test "#4375: UTF-8 characters in comments", ->
  # 智に働けば角が立つ、情に掉させば流される。
  ok yes

test "#4290: Block comments in array literals", ->
  arr = [
    ###  ###
    3
    ###
      What is the meaning of life, the universe, and everything?
    ###
    42
  ]
  arrayEq arr, [3, 42]

test "Block comments in array literals are properly indented 1", ->
  eqJS '''
  arr = [
    ### ! ###
    3
    42
  ]''', '''
  var arr;

  arr = [/* ! */ 3, 42];'''

test "Block comments in array literals are properly indented 2", ->
  eqJS '''
  arr = [
    ###  ###
    3
    ###
      What is the meaning of life, the universe, and everything?
    ###
    42
  ]''', '''
  var arr;

  arr = [
    /*  */
    3,
    /*
      What is the meaning of life, the universe, and everything?
    */
    42
  ];'''

test "Block comments in array literals are properly indented 3", ->
  eqJS '''
  arr = [
    ###
      How many stooges are there?
    ###
    3
    ### Who’s on first? ###
    'Who'
  ]''', '''
  var arr;

  arr = [
    /*
      How many stooges are there?
    */
    3,
    /* Who’s on first? */
    'Who'
  ];'''

test "Block comments in array literals are properly indented 4", ->
  eqJS '''
  if yes
    arr = [
      1
      ###
        How many stooges are there?
      ###
      3
      ### Who’s on first? ###
      'Who'
    ]''', '''
  var arr;

  if (true) {
    arr = [
      1,
      /*
        How many stooges are there?
      */
      3,
      /* Who’s on first? */
      'Who'
    ];
  }'''

test "Line comments in array literals are properly indented 1", ->
  eqJS '''
  arr = [
    # How many stooges are there?
    3
    # Who’s on first?
    'Who'
  ]''', '''
  var arr;

  arr = [
    // How many stooges are there?
    3,
    // Who’s on first?
    'Who'
  ];'''

test "Line comments in array literals are properly indented 2", ->
  eqJS '''
  arr = [
    # How many stooges are there?
    3
    # Who’s on first?
    'Who'
    # Who?
    {
      firstBase: 'Who'
      secondBase: 'What'
      leftField: 'Why'
    }
  ]''', '''
  var arr;

  arr = [
    // How many stooges are there?
    3,
    // Who’s on first?
    'Who',
    {
      // Who?
      firstBase: 'Who',
      secondBase: 'What',
      leftField: 'Why'
    }
  ];'''

test "Block comments trailing their attached token are properly indented", ->
  eqJS '''
  if indented
    if indentedAgain
      a
      ###
        Multiline
        comment
      ###
    a
  ''', '''
  if (indented) {
    if (indentedAgain) {
      a;
    }
    /*
      Multiline
      comment
    */
    a;
  }
  '''

test "Comments in proper order 1", ->
  eqJS '''
  # 1
  ### 2 ###
  # 3
  ''', '''
  // 1
  /* 2 */
  // 3
  '''

test "Comments in proper order 2", ->
  eqJS '''
  if indented
    # 1
    ### 2 ###
    # 3
    a
  ''', '''
  if (indented) {
    // 1
    /* 2 */
    // 3
    a;
  }
  '''

test "Line comment above interpolated string", ->
  eqJS '''
  if indented
    # comment
    "#{1}"
  ''', '''
  if (indented) {
    // comment
    `${1}`;
  }'''

test "Line comment above interpolated string object key", ->
  eqJS '''
  {
    # comment
    "#{1}": 2
  }
  ''', '''
  ({
    // comment
    [`${1}`]: 2
  });'''

test "Line comments in classes are properly indented", ->
  eqJS '''
  class A extends B
    # This is a fine class.
    # I could tell you all about it, but what else do you need to know?
    constructor: ->
      # Something before `super`
      super()

    # This next method is a doozy!
    # A doozy, I tell ya!
    method: ->
      # Whoa.
      # Can you believe it?
      no

    ### Look out, incoming! ###
    anotherMethod: ->
      ### Ha! ###
      off
  ''', '''
  var A;

  A = class A extends B {
    // This is a fine class.
    // I could tell you all about it, but what else do you need to know?
    constructor() {
      // Something before `super`
      super();
    }

    // This next method is a doozy!
    // A doozy, I tell ya!
    method() {
      // Whoa.
      // Can you believe it?
      return false;
    }

    /* Look out, incoming! */
    anotherMethod() {
      /* Ha! */
      return false;
    }

  };'''

test "Line comments are properly indented", ->
  eqJS '''
  # Unindented comment
  if yes
    # Comment indented one tab
    1
    if yes
      # Comment indented two tabs
      2
    else
      # Another comment indented two tabs
      # Yet another comment indented two tabs
      3
  else
    # Another comment indented one tab
    # Yet another comment indented one tab
    4

  # Another unindented comment''', '''
  // Unindented comment
  if (true) {
    // Comment indented one tab
    1;
    if (true) {
      // Comment indented two tabs
      2;
    } else {
      // Another comment indented two tabs
      // Yet another comment indented two tabs
      3;
    }
  } else {
    // Another comment indented one tab
    // Yet another comment indented one tab
    4;
  }

  // Another unindented comment'''

test "Line comments that trail code, followed by line comments that start a new line", ->
  eqJS '''
  a = ->
    b 1 # Trailing comment

  # Comment that starts a new line
  2
  ''', '''
  var a;

  a = function() {
    return b(1); // Trailing comment
  };


  // Comment that starts a new line
  2;
  '''

test "Empty lines between comments are preserved", ->
  eqJS '''
  if indented
    # 1

    # 2
    3
  ''', '''
  if (indented) {
    // 1

    // 2
    3;
  }'''

test "Block comment in an interpolated string", ->
  eqJS '"a#{### Comment ###}b"', "`a${/* Comment */''}b`;"
  eqJS '"a#{### 1 ###}b#{### 2 ###}c"', "`a${/* 1 */''}b${/* 2 */''}c`;"

test "#4629: Block comment in CSX interpolation", ->
  eqJS '<div>{### Comment ###}</div>', '<div>{/* Comment */}</div>;'
  eqJS '''
  <div>
  {###
    Multiline
    Comment
  ###}
  </div>''', '''
  <div>
  {/*
    Multiline
    Comment
  */}
  </div>;'''

test "Line comment in an interpolated string", ->
  eqJS '''
  "a#{# Comment
  1}b"
  ''', '''
  `a${// Comment
  1}b`;'''

test "Line comments before `throw`", ->
  eqJS '''
  if indented
    1/0
    # Uh-oh!
    # You really shouldn’t have done that.
    throw DivideByZeroError()
  ''', '''
  if (indented) {
    1 / 0;
    // Uh-oh!
    // You really shouldn’t have done that.
    throw DivideByZeroError();
  }'''

test "Comments before if this exists", ->
  js = CoffeeScript.compile '''
  1
  # Comment
  if @huh?
    2
  '''
  ok js.includes '// Comment'

test "Comment before unary (`not`)", ->
  js = CoffeeScript.compile '''
  1
  # Comment
  if not doubleNegative
    dontDoIt()
  '''
  ok js.includes '// Comment'

test "Comments before postfix", ->
  js = CoffeeScript.compile '''
  # 1
  2

  # 3
  return unless window?

  ### 4 ###
  return if global?
  '''
  ok js.includes '// 3'
  ok js.includes '/* 4 */'

test "Comments before assignment if", ->
  js = CoffeeScript.compile '''
  1
  # Line comment
  a = if b
    3
  else
    4

  ### Block comment ###
  c = if d
    5
  '''
  ok js.includes '// Line comment'
  ok js.includes '/* Block comment */'

test "Comments before for loop", ->
  js = CoffeeScript.compile '''
  1
  # Comment
  for drop in ocean
    drink drop
  '''
  ok js.includes '// Comment'

test "Comments after for loop", ->
  js = CoffeeScript.compile '''
  for drop in ocean # Comment after source variable
    drink drop
  for i in [1, 2] # Comment after array literal element
    count i
  for key, val of {a: 1} # Comment after object literal
    turn key
  '''
  ok js.includes '// Comment after source variable'
  ok js.includes '// Comment after array literal element'
  ok js.includes '// Comment after object literal'

test "Comments before soak", ->
  js = CoffeeScript.compile '''
  # 1
  2

  # 3
  return unless window?.location?.hash

  ### 4 ###
  return if process?.env?.ENV
  '''
  ok js.includes '// 3'
  ok js.includes '/* 4 */'

test "Comments before splice", ->
  js = CoffeeScript.compile '''
  1
  # Comment
  a[1..2] = [1, 2, 3]
  '''
  ok js.includes '// Comment'

test "Comments before object destructuring", ->
  js = CoffeeScript.compile '''
  1
  # Comment before splat token
  { x... } = { a: 1, b: 2 }

  # Comment before destructured token
  { x, y, z... } = { x: 1, y: 2, a: 3, b: 4 }
  '''
  ok js.includes 'Comment before splat token'
  ok js.includes 'Comment before destructured token'

test "Comment before splat function parameter", ->
  js = CoffeeScript.compile '''
  1
  # Comment
  (blah..., yadda) ->
  '''
  ok js.includes 'Comment'

test "Comments before static method", ->
  eqJS '''
  class Child extends Base
    # Static method:
    @method = ->
  ''', '''
  var Child;

  Child = class Child extends Base {
    // Static method:
    static method() {}

  };'''

test "Comment before method that calls `super()`", ->
  eqJS '''
  class Dismissed
    # Before a method calling `super`
    method: ->
      super()
  ''', '''
  var Dismissed;

  Dismissed = class Dismissed {
    // Before a method calling `super`
    method() {
      return super.method();
    }

  };
  '''

test "Comment in interpolated regex", ->
  js = CoffeeScript.compile '''
  1
  ///
    #{1}
    # Comment
  ///
  '''
  ok js.includes 'Comment'

test "Line comment after line continuation", ->
  eqJS '''
  1 + \\ # comment
    2
  ''', '''
  1 + 2; // comment
  '''

test "Comments appear above scope `var` declarations", ->
  eqJS '''
  # @flow

  fn = (str) -> str
  ''', '''
  // @flow
  var fn;

  fn = function(str) {
    return str;
  };'''

test "Block comments can appear with function arguments", ->
  eqJS '''
  fn = (str ###: string ###, num ###: number ###) -> str + num
  ''', '''
  var fn;

  fn = function(str/*: string */, num/*: number */) {
    return str + num;
  };'''

test "Block comments can appear between function parameters and function opening brace", ->
  eqJS '''
  fn = (str ###: string ###, num ###: number ###) ###: string ### ->
    str + num
  ''', '''
  var fn;

  fn = function(str/*: string */, num/*: number */)/*: string */ {
    return str + num;
  };'''

test "Flow comment-based syntax support", ->
  eqJS '''
  # @flow

  fn = (str ###: string ###, num ###: number ###) ###: string ### ->
    str + num
  ''', '''
  // @flow
  var fn;

  fn = function(str/*: string */, num/*: number */)/*: string */ {
    return str + num;
  };'''

test "#4706: Flow comments around function parameters", ->
  eqJS '''
  identity = ###::<T>### (value ###: T ###) ###: T ### ->
    value
  ''', '''
  var identity;

  identity = function/*::<T>*/(value/*: T */)/*: T */ {
    return value;
  };'''

test "#4706: Flow comments around function parameters", ->
  eqJS '''
  copy = arr.map(###:: <T> ###(item ###: T ###) ###: T ### => item)
  ''', '''
  var copy;

  copy = arr.map(/*:: <T> */(item/*: T */)/*: T */ => {
    return item;
  });'''

test "#4706: Flow comments after class name", ->
  eqJS '''
  class Container ###::<T> ###
    method: ###::<U> ### () -> true
  ''', '''
  var Container;

  Container = class Container/*::<T> */ {
    method() {
      return true;
    }

  };'''

test "#4706: Identifiers with comments wrapped in parentheses remain wrapped", ->
  eqJS '(arr ###: Array<number> ###)', '(arr/*: Array<number> */);'
  eqJS 'other = (arr ###: any ###)', '''
  var other;

  other = (arr/*: any */);'''

test "#4706: Flow comments before class methods", ->
  eqJS '''
  class Container
    ###::
    method: (number) => string;
    method: (string) => number;
    ###
    method: -> true
  ''', '''
  var Container;

  Container = class Container {
    /*::
    method: (number) => string;
    method: (string) => number;
    */
    method() {
      return true;
    }

  };'''

test "#4706: Flow comments for class method params", ->
  eqJS '''
  class Container
    method: (param ###: string ###) -> true
  ''', '''
  var Container;

  Container = class Container {
    method(param/*: string */) {
      return true;
    }

  };'''

test "#4706: Flow comments for class method returns", ->
  eqJS '''
  class Container
    method: () ###: string ### -> true
  ''', '''
  var Container;

  Container = class Container {
    method()/*: string */ {
      return true;
    }

  };'''

test "#4706: Flow comments for function spread", ->
  eqJS '''
  method = (...rest ###: Array<string> ###) =>
  ''', '''
  var method;

  method = (...rest/*: Array<string> */) => {};'''

test "#4747: Flow comments for local variable declaration", ->
  eqJS 'a ###: number ### = 1', '''
  var a/*: number */;

  a = 1;
  '''

test "#4747: Flow comments for local variable declarations", ->
  eqJS '''
  a ###: number ### = 1
  b ###: string ### = 'c'
  ''', '''
  var a/*: number */, b/*: string */;

  a = 1;

  b = 'c';
  '''

test "#4747: Flow comments for local variable declarations with reassignment", ->
  eqJS '''
  a ###: number ### = 1
  b ###: string ### = 'c'
  a ### some other comment ### = 2
  ''', '''
  var a/*: number */, b/*: string */;

  a = 1;

  b = 'c';

  a/* some other comment */ = 2;
  '''

test "#4756: Comment before ? operation", ->
  eqJS '''
  do ->
    ### Comment ###
    @foo ? 42
  ''', '''
  (function() {
    var ref;
    /* Comment */
    return (ref = this.foo) != null ? ref : 42;
  })();
  '''