mirror of
https://github.com/NixOS/nixpkgs.git
synced 2024-12-30 01:23:03 +00:00
efdf618330
Since the `assertOneOf` uses `lib.generators`, they are not really trivial anymore and should go into their own library file.
45 lines
1.2 KiB
Nix
45 lines
1.2 KiB
Nix
{ lib }:
|
|
|
|
rec {
|
|
|
|
/* Print a trace message if pred is false.
|
|
Intended to be used to augment asserts with helpful error messages.
|
|
|
|
Example:
|
|
assertMsg false "nope"
|
|
=> false
|
|
stderr> trace: nope
|
|
|
|
assert (assertMsg ("foo" == "bar") "foo is not bar, silly"); ""
|
|
stderr> trace: foo is not bar, silly
|
|
stderr> assert failed at …
|
|
|
|
Type:
|
|
assertMsg :: Bool -> String -> Bool
|
|
*/
|
|
# TODO(Profpatsch): add tests that check stderr
|
|
assertMsg = pred: msg:
|
|
if pred
|
|
then true
|
|
else builtins.trace msg false;
|
|
|
|
/* Specialized `assertMsg` for checking if val is one of the elements
|
|
of a list. Useful for checking enums.
|
|
|
|
Example:
|
|
let sslLibrary = "libressl"
|
|
in assertOneOf "sslLibrary" sslLibrary [ "openssl" "bearssl" ]
|
|
=> false
|
|
stderr> trace: sslLibrary must be one of "openssl", "bearssl", but is: "libressl"
|
|
|
|
Type:
|
|
assertOneOf :: String -> ComparableVal -> List ComparableVal -> Bool
|
|
*/
|
|
assertOneOf = name: val: xs: assertMsg
|
|
(lib.elem val xs)
|
|
"${name} must be one of ${
|
|
lib.generators.toPretty {} xs}, but is: ${
|
|
lib.generators.toPretty {} val}";
|
|
|
|
}
|