lib/types: Add emptyValue attribute to types

Co-Authored-By: Robert Hensing <roberth@users.noreply.github.com>
This commit is contained in:
Silvan Mosberger 2019-12-13 01:12:41 +01:00
parent d5a2922641
commit 4268b4f9cf
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@ -65,6 +65,11 @@ rec {
# definition values and locations (e.g. [ { file = "/foo.nix";
# value = 1; } { file = "/bar.nix"; value = 2 } ]).
merge ? mergeDefaultOption
, # Whether this type has a value representing nothingness. If it does,
# this should be a value of the form { value = <the nothing value>; }
# If it doesn't, this should be {}
# This may be used when a value is required for `mkIf false`. This allows the extra laziness in e.g. `lazyAttrsOf`.
emptyValue ? {}
, # Return a flat list of sub-options. Used to generate
# documentation.
getSubOptions ? prefix: {}
@ -88,7 +93,7 @@ rec {
functor ? defaultFunctor name
}:
{ _type = "option-type";
inherit name check merge getSubOptions getSubModules substSubModules typeMerge functor;
inherit name check merge emptyValue getSubOptions getSubModules substSubModules typeMerge functor;
description = if description == null then name else description;
};
@ -225,6 +230,7 @@ rec {
description = "attribute set";
check = isAttrs;
merge = loc: foldl' (res: def: mergeAttrs res def.value) {};
emptyValue = { value = {}; };
};
# derivation is a reserved keyword.
@ -265,6 +271,7 @@ rec {
) def.value
else
throw "The option value `${showOption loc}` in `${def.file}` is not a list.") defs)));
emptyValue = { value = {}; };
getSubOptions = prefix: elemType.getSubOptions (prefix ++ ["*"]);
getSubModules = elemType.getSubModules;
substSubModules = m: listOf (elemType.substSubModules m);
@ -273,7 +280,10 @@ rec {
nonEmptyListOf = elemType:
let list = addCheck (types.listOf elemType) (l: l != []);
in list // { description = "non-empty " + list.description; };
in list // {
description = "non-empty " + list.description;
# Note: emptyValue is left as is, because another module may define an element.
};
attrsOf = elemType: mkOptionType rec {
name = "attrsOf";
@ -285,6 +295,7 @@ rec {
)
# Push down position info.
(map (def: mapAttrs (n: v: { inherit (def) file; value = v; }) def.value) defs)));
emptyValue = { value = {}; };
getSubOptions = prefix: elemType.getSubOptions (prefix ++ ["<name>"]);
getSubModules = elemType.getSubModules;
substSubModules = m: attrsOf (elemType.substSubModules m);
@ -339,6 +350,7 @@ rec {
description = "list or attribute set of ${elemType.description}s";
check = x: isList x || isAttrs x;
merge = loc: defs: attrOnly.merge loc (convertAllLists loc defs);
emptyValue = { value = {}; };
getSubOptions = prefix: elemType.getSubOptions (prefix ++ ["<name?>"]);
getSubModules = elemType.getSubModules;
substSubModules = m: loaOf (elemType.substSubModules m);
@ -350,6 +362,7 @@ rec {
name = "uniq";
inherit (elemType) description check;
merge = mergeOneOption;
emptyValue = elemType.emptyValue;
getSubOptions = elemType.getSubOptions;
getSubModules = elemType.getSubModules;
substSubModules = m: uniq (elemType.substSubModules m);
@ -367,6 +380,7 @@ rec {
else if nrNulls != 0 then
throw "The option `${showOption loc}` is defined both null and not null, in ${showFiles (getFiles defs)}."
else elemType.merge loc defs;
emptyValue = { value = null; };
getSubOptions = elemType.getSubOptions;
getSubModules = elemType.getSubModules;
substSubModules = m: nullOr (elemType.substSubModules m);
@ -407,6 +421,7 @@ rec {
args.name = last loc;
prefix = loc;
}).config;
emptyValue = { value = {}; };
getSubOptions = prefix: (evalModules
{ inherit modules prefix specialArgs;
# This is a work-around due to the fact that some sub-modules,
@ -515,6 +530,7 @@ rec {
if finalType.check val then val
else coerceFunc val;
in finalType.merge loc (map (def: def // { value = coerceVal def.value; }) defs);
emptyValue = finalType.emptyValue;
getSubOptions = finalType.getSubOptions;
getSubModules = finalType.getSubModules;
substSubModules = m: coercedTo coercedType coerceFunc (finalType.substSubModules m);