| 1 | # spec/ysh-builtin-error
|
| 2 |
|
| 3 | ## our_shell: ysh
|
| 4 | ## oils_failures_allowed: 0
|
| 5 |
|
| 6 | #### try expects an argument
|
| 7 |
|
| 8 | try
|
| 9 | echo status=$?
|
| 10 |
|
| 11 | ## status: 3
|
| 12 | ## STDOUT:
|
| 13 | ## END
|
| 14 |
|
| 15 | #### User errors behave like builtin errors
|
| 16 | func divide(a, b) {
|
| 17 | if (b === 0) {
|
| 18 | error 'divide by zero' (status=3)
|
| 19 | }
|
| 20 |
|
| 21 | return (a / b)
|
| 22 | }
|
| 23 |
|
| 24 | # errors can be caught with try
|
| 25 | try { = divide(42, 0) }
|
| 26 | echo status=$_status
|
| 27 |
|
| 28 | = divide(42, 0) # sets status to 3
|
| 29 | ## status: 3
|
| 30 | ## STDOUT:
|
| 31 | status=3
|
| 32 | ## END
|
| 33 |
|
| 34 | #### _error register is initially empty dict
|
| 35 |
|
| 36 | echo $[type(_error)]
|
| 37 | echo $[len(_error)]
|
| 38 |
|
| 39 | ## STDOUT:
|
| 40 | Dict
|
| 41 | 0
|
| 42 | ## END
|
| 43 |
|
| 44 | #### Error sets _error.message, which can be used by programs
|
| 45 |
|
| 46 | func divide(a, b) {
|
| 47 | if (b === 0) {
|
| 48 | error "divide by zero: $a / $b" (status=3)
|
| 49 | }
|
| 50 | return (a / b)
|
| 51 | }
|
| 52 |
|
| 53 | try { = divide(42, 0) }
|
| 54 | echo status=$_status
|
| 55 | echo message=$[_error.message]
|
| 56 |
|
| 57 | proc p {
|
| 58 | echo $[divide(5, 0)]
|
| 59 | }
|
| 60 |
|
| 61 | try { p }
|
| 62 | echo status=$_status
|
| 63 | echo message=$[_error.message]
|
| 64 |
|
| 65 | # Design bug: this isn't caught!
|
| 66 |
|
| 67 | # try echo $[divide(3, 0]
|
| 68 |
|
| 69 | ## STDOUT:
|
| 70 | status=3
|
| 71 | message=divide by zero: 42 / 0
|
| 72 | status=3
|
| 73 | message=divide by zero: 5 / 0
|
| 74 | ## END
|
| 75 |
|
| 76 | #### error builtin adds named args as properties on _error Dict
|
| 77 |
|
| 78 | try {
|
| 79 | error 'bad' (status=99)
|
| 80 | }
|
| 81 | pp line (_error)
|
| 82 |
|
| 83 | # Note: myData co
|
| 84 | try {
|
| 85 | error 'bad' (status=99, myData={spam:'eggs'})
|
| 86 | }
|
| 87 | pp line (_error)
|
| 88 |
|
| 89 | try {
|
| 90 | error 'bad' (status=99, message='cannot override')
|
| 91 | }
|
| 92 | pp line (_error)
|
| 93 |
|
| 94 | ## STDOUT:
|
| 95 | (Dict) {"status":99,"message":"bad"}
|
| 96 | (Dict) {"myData":{"spam":"eggs"},"status":99,"message":"bad"}
|
| 97 | (Dict) {"message":"bad","status":99}
|
| 98 | ## END
|
| 99 |
|
| 100 | #### Errors within multiple functions
|
| 101 | func inverse(x) {
|
| 102 | if (x === 0) {
|
| 103 | error '0 does not have an inverse' # default status is 1
|
| 104 | }
|
| 105 |
|
| 106 | return (1 / x)
|
| 107 | }
|
| 108 |
|
| 109 | func invertList(list) {
|
| 110 | var result = []
|
| 111 | for item in (list) {
|
| 112 | call result->append(inverse(item))
|
| 113 | }
|
| 114 | return (result)
|
| 115 | }
|
| 116 |
|
| 117 | = invertList([1, 2, 0])
|
| 118 | ## status: 10
|
| 119 | ## STDOUT:
|
| 120 | ## END
|
| 121 |
|
| 122 | #### Impact of errors on var declaration
|
| 123 | func alwaysError() {
|
| 124 | error "it's an error" (status=100)
|
| 125 | }
|
| 126 |
|
| 127 | try {
|
| 128 | var mylist = [1 + 2, alwaysError()]
|
| 129 |
|
| 130 | echo this will never be printed
|
| 131 | }
|
| 132 | = mylist # undefined! status becomes 1
|
| 133 | ## status: 1
|
| 134 | ## STDOUT:
|
| 135 | ## END
|
| 136 |
|
| 137 | #### Error defaults status to 10
|
| 138 | error 'some error'
|
| 139 | ## status: 10
|
| 140 | ## STDOUT:
|
| 141 | ## END
|
| 142 |
|
| 143 | #### Error expects an int status
|
| 144 | error 'error' (status='a string?')
|
| 145 | ## status: 3
|
| 146 | ## STDOUT:
|
| 147 | ## END
|
| 148 |
|
| 149 | #### Error typed arg, not named arg
|
| 150 | error msg (100)
|
| 151 | ## status: 3
|
| 152 | ## STDOUT:
|
| 153 | ## END
|
| 154 |
|
| 155 | #### Errors cannot take command args
|
| 156 | error uh-oh ('error', status=1)
|
| 157 | ## status: 3
|
| 158 | ## STDOUT:
|
| 159 | ## END
|
| 160 |
|
| 161 | #### Error must take arguments
|
| 162 | error
|
| 163 | ## status: 2
|
| 164 | ## STDOUT:
|
| 165 | ## END
|
| 166 |
|
| 167 | #### Errors cannot have a status of 0
|
| 168 | error ('error', status=0)
|
| 169 | ## status: 2
|
| 170 | ## STDOUT:
|
| 171 | ## END
|
| 172 |
|
| 173 | #### try { error oops }
|
| 174 |
|
| 175 | try { error oops }
|
| 176 | echo status=$_status
|
| 177 |
|
| 178 | ## STDOUT:
|
| 179 | status=10
|
| 180 | ## END
|