1+ # Strict Early Errors
2+ # -------------------
3+
4+ # The following are prohibited under ES5's `strict` mode
5+ # * `Octal Integer Literals`
6+ # * `Octal Escape Sequences`
7+ # * duplicate property definitions in `Object Literal`s
8+ # * duplicate formal parameter
9+ # * `delete` operand is a variable
10+ # * `delete` operand is a parameter
11+ # * `delete` operand is `undefined`
12+ # * `Future Reserved Word`s as identifiers: implements, interface, let, package, private, protected, public, static, yield
13+ # * `eval` or `arguments` as `catch` identifier
14+ # * `eval` or `arguments` as formal parameter
15+ # * `eval` or `arguments` as function declaration identifier
16+ # * `eval` or `arguments` as LHS of assignment
17+ # * `eval` or `arguments` as the operand of a post/pre-fix inc/dec-rement expression
18+
19+ # helper to assert that code complies with strict prohibitions
20+ strict = (code , msg ) ->
21+ throws (-> CoffeeScript .compile code), null , msg
22+ strictOk = (code , msg ) ->
23+ doesNotThrow (-> CoffeeScript .compile code), msg
24+
25+
26+ test " Octal Integer Literals prohibited" ->
27+ strict ' n = 01'
28+ strict ' n = 07777'
29+ strictOk ' n = 09'
30+ strictOk ' n = 079'
31+ strictOk ' n = `01`'
32+
33+ test " Octal Escape Sequences prohibited" ->
34+ strict ' e = "\\ 01"'
35+ strict ' e = "\\ 0777"'
36+ strictOk ' e = "\\ 09"'
37+ strictOk ' e = "\\ 07777"'
38+ strictOk " e = `'\033 [0;1m'`"
39+
40+ test " duplicate property definitions in `Object Literal`s are prohibited" ->
41+ strict ' o = {x:1,x:1}'
42+ strict ' x = 1; o = {x, x: 2}'
43+
44+ test " duplicate formal parameter are prohibited" ->
45+ nonce = {}
46+
47+ # a Param can be an Identifier, ThisProperty( @-param ), Array, or Object
48+ # a Param can also be a splat (...) or an assignment (param=value)
49+ # the following function expressions should throw errors
50+ strict ' (_,_)->' ' param, param'
51+ strict ' (_,@_)->' ' param, @param'
52+ strict ' (_,_...)->' ' param, param...'
53+ strict ' (@_,_...)->' ' @param, param...'
54+ strict ' (_,_ = true)->' ' param, param='
55+ strict ' (@_,@_)->' ' two @params'
56+ strict ' (_,@_ = true)->' ' param, @param='
57+ strict ' (_,{_})->' ' param, {param}'
58+ strict ' (@_,{_})->' ' @param, {param}'
59+ strict ' ({_,_})->' ' {param, param}'
60+ strict ' ({_,@_})->' ' {param, @param}'
61+ strict ' (_,[_])->' ' param, [param]'
62+ strict ' ([_,_])->' ' [param, param]'
63+ strict ' ([_,@_])->' ' [param, @param]'
64+ strict ' (_,[_]=true)->' ' param, [param]='
65+ strict ' (_,[@_,{_}])->' ' param, [@param, {param}]'
66+ strict ' (_,[_,{@_}])->' ' param, [param, {@param}]'
67+ strict ' (_,[_,{_}])->' ' param, [param, {param}]'
68+ strict ' (_,[_,{__}])->' ' param, [param, {param2}]'
69+ strict ' (_,[__,{_}])->' ' param, [param2, {param}]'
70+ strict ' (__,[_,{_}])->' ' param, [param2, {param2}]'
71+ # the following function expressions should **not** throw errors
72+ strictOk ' ({},_arg)->'
73+ strictOk ' ({},{})->'
74+ strictOk ' ([]...,_arg)->'
75+ strictOk ' ({}...,_arg)->'
76+ strictOk ' ({}...,[],_arg)->'
77+ strictOk ' ([]...,{},_arg)->'
78+ strictOk ' (@case,_case)->'
79+ strictOk ' (@case,_case...)->'
80+ strictOk ' (@case...,_case)->'
81+ strictOk ' (_case,@case)->'
82+ strictOk ' (_case,@case...)->'
83+
84+ test " `delete` operand is a var is prohibited" ->
85+ strict ' a = 1; delete a'
86+ strictOk ' delete a' # noop
87+
88+ test " `delete` operand is a parameter is prohibited" ->
89+ strict ' (a) -> delete a'
90+ strict ' (@a) -> delete a'
91+ strict ' (a...) -> delete a'
92+ strict ' (a = 1) -> delete a'
93+ strict ' ([a]) -> delete a'
94+ strict ' ({a}) -> delete a'
95+
96+ test " `Future Reserved Word`s as identifiers prohibited" ->
97+ futures = ' implements interface let package private protected public static yield' split ' '
98+ for keyword in futures
99+ strict " #{ keyword} "
100+ strict " class #{ keyword} "
101+ strict " try new Error catch #{ keyword} "
102+ strict " (#{ keyword} "
103+ strict " {keyword}++"
104+ strict " ++{keyword}"
105+ strict " {keyword}--"
106+ strict " --{keyword}"
107+
108+ test " `eval` and `arguments` use restricted" ->
109+ proscribeds = ' eval arguments' split ' '
110+ for proscribed in proscribeds
111+ strict " #{ proscribed} "
112+ strict " class #{ proscribed} "
113+ strict " try new Error catch #{ proscribed} "
114+ strict " (#{ proscribed} "
115+ strict " {proscribed}++"
116+ strict " ++{proscribed}"
117+ strict " {proscribed}--"
118+ strict " --{proscribed}"
119+ strictOk " eval 'true'"
120+ strictOk " -> arguments[0]"
121+
122+
123+
124+
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