1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
|
when not declared(sysFatal):
include "system/fatal"
# ---------------------------------------------------------------------------
# helpers
type InstantiationInfo = tuple[filename: string, line: int, column: int]
proc `$`(x: int): string {.magic: "IntToStr", noSideEffect.}
proc `$`(info: InstantiationInfo): string =
# The +1 is needed here
# instead of overriding `$` (and changing its meaning), consider explicit name.
info.filename & "(" & $info.line & ", " & $(info.column+1) & ")"
# ---------------------------------------------------------------------------
proc raiseAssert*(msg: string) {.noinline, noreturn.} =
sysFatal(AssertionError, msg)
proc failedAssertImpl*(msg: string) {.raises: [], tags: [].} =
# trick the compiler to not list ``AssertionError`` when called
# by ``assert``.
type Hide = proc (msg: string) {.noinline, raises: [], noSideEffect,
tags: [].}
Hide(raiseAssert)(msg)
template assertImpl(cond: bool, msg: string, expr: string, enabled: static[bool]) =
when enabled:
const
loc = instantiationInfo(fullPaths = compileOption("excessiveStackTrace"))
ploc = $loc
bind instantiationInfo
mixin failedAssertImpl
{.line: loc.}:
if not cond:
failedAssertImpl(ploc & " `" & expr & "` " & msg)
template assert*(cond: untyped, msg = "") =
## Raises ``AssertionError`` with `msg` if `cond` is false. Note
## that ``AssertionError`` is hidden from the effect system, so it doesn't
## produce ``{.raises: [AssertionError].}``. This exception is only supposed
## to be caught by unit testing frameworks.
##
## The compiler may not generate any code at all for ``assert`` if it is
## advised to do so through the ``-d:release`` or ``--assertions:off``
## `command line switches <nimc.html#command-line-switches>`_.
const expr = astToStr(cond)
assertImpl(cond, msg, expr, compileOption("assertions"))
template doAssert*(cond: untyped, msg = "") =
## Similar to ``assert`` but is always turned on regardless of ``--assertions``.
const expr = astToStr(cond)
assertImpl(cond, msg, expr, true)
template onFailedAssert*(msg, code: untyped): untyped {.dirty.} =
## Sets an assertion failure handler that will intercept any assert
## statements following `onFailedAssert` in the current module scope.
##
## .. code-block:: nim
## # module-wide policy to change the failed assert
## # exception type in order to include a lineinfo
## onFailedAssert(msg):
## var e = new(TMyError)
## e.msg = msg
## e.lineinfo = instantiationInfo(-2)
## raise e
##
template failedAssertImpl(msgIMPL: string): untyped {.dirty.} =
let msg = msgIMPL
code
template doAssertRaises*(exception: typedesc, code: untyped) =
## Raises ``AssertionError`` if specified ``code`` does not raise the
## specified exception. Example:
##
## .. code-block:: nim
## doAssertRaises(ValueError):
## raise newException(ValueError, "Hello World")
var wrong = false
when Exception is exception:
try:
if true:
code
wrong = true
except Exception:
discard
else:
try:
if true:
code
wrong = true
except exception:
discard
except Exception:
raiseAssert(astToStr(exception) &
" wasn't raised, another error was raised instead by:\n"&
astToStr(code))
if wrong:
raiseAssert(astToStr(exception) & " wasn't raised by:\n" & astToStr(code))
|