forked from mirrors/nixpkgs
312 lines
11 KiB
Nix
312 lines
11 KiB
Nix
# Nixpkgs/NixOS option handling.
|
||
|
||
let lib = import ./default.nix; in
|
||
|
||
with { inherit (builtins) head length; };
|
||
with import ./trivial.nix;
|
||
with import ./lists.nix;
|
||
with import ./misc.nix;
|
||
with import ./attrsets.nix;
|
||
with import ./properties.nix;
|
||
|
||
rec {
|
||
|
||
inherit (lib) typeOf;
|
||
|
||
|
||
isOption = attrs: (typeOf attrs) == "option";
|
||
mkOption = attrs: attrs // {
|
||
_type = "option";
|
||
# name (this is the name of the attributem it is automatically generated by the traversal)
|
||
# default (value used when no definition exists)
|
||
# example (documentation)
|
||
# description (documentation)
|
||
# type (option type, provide a default merge function and ensure type correctness)
|
||
# merge (function used to merge definitions into one definition: [ /type/ ] -> /type/)
|
||
# apply (convert the option value to ease the manipulation of the option result)
|
||
# options (set of sub-options declarations & definitions)
|
||
# extraConfigs (list of possible configurations)
|
||
};
|
||
|
||
mapSubOptions = f: opt:
|
||
if opt ? options then
|
||
opt // {
|
||
options = map f (toList opt.options);
|
||
}
|
||
else
|
||
opt;
|
||
|
||
# Make the option declaration more user-friendly by adding default
|
||
# settings and some verifications based on the declaration content (like
|
||
# type correctness).
|
||
addOptionMakeUp = {name, recurseInto}: decl:
|
||
let
|
||
init = {
|
||
inherit name;
|
||
merge = mergeDefaultOption;
|
||
apply = lib.id;
|
||
};
|
||
|
||
functionsFromType = opt:
|
||
if decl ? type && decl.type ? merge then
|
||
opt
|
||
// optionalAttrs (decl.type ? merge) { inherit (decl.type) merge; }
|
||
// optionalAttrs (decl.type ? check) { inherit (decl.type) check; }
|
||
else
|
||
opt;
|
||
|
||
addDeclaration = opt: opt // decl;
|
||
|
||
ensureMergeInputType = opt:
|
||
if opt ? check then
|
||
opt // {
|
||
merge = list:
|
||
if all opt.check list then
|
||
opt.merge list
|
||
else
|
||
throw "One of the definitions has a bad type.";
|
||
}
|
||
else opt;
|
||
|
||
ensureDefaultType = opt:
|
||
if opt ? check && opt ? default then
|
||
opt // {
|
||
default =
|
||
if opt.check opt.default then
|
||
opt.default
|
||
else
|
||
throw "The default value has a bad type.";
|
||
}
|
||
else opt;
|
||
|
||
handleOptionSets = opt:
|
||
if opt ? type && opt.type.hasOptions then
|
||
let
|
||
|
||
optionConfig = vals: args:
|
||
map (f: lib.applyIfFunction f args)
|
||
(opt.options ++ toList vals);
|
||
|
||
# Evaluate sub-modules.
|
||
subModuleMerge = path: vals:
|
||
lib.fix (args:
|
||
let
|
||
result = recurseInto path (optionConfig vals args);
|
||
name = lib.removePrefix (opt.name + ".") path;
|
||
extraArgs = opt.extraArgs or {};
|
||
individualExtraArgs = opt.individualExtraArgs or {};
|
||
in {
|
||
inherit (result) config options;
|
||
inherit name;
|
||
} //
|
||
(opt.extraArgs or {}) //
|
||
(if hasAttr name individualExtraArgs then getAttr name individualExtraArgs else {})
|
||
);
|
||
|
||
# Add _options in sub-modules to make it viewable from other
|
||
# modules.
|
||
subModuleMergeConfig = path: vals:
|
||
let result = subModuleMerge path vals; in
|
||
{ _args = result; } // result.config;
|
||
|
||
in
|
||
opt // {
|
||
merge = list:
|
||
opt.type.iter
|
||
subModuleMergeConfig
|
||
opt.name
|
||
(opt.merge list);
|
||
options =
|
||
let path = opt.type.docPath opt.name; in
|
||
(subModuleMerge path []).options;
|
||
}
|
||
else
|
||
opt;
|
||
in
|
||
foldl (opt: f: f opt) init [
|
||
# default settings
|
||
functionsFromType
|
||
|
||
# user settings
|
||
addDeclaration
|
||
|
||
# override settings
|
||
ensureMergeInputType
|
||
ensureDefaultType
|
||
handleOptionSets
|
||
];
|
||
|
||
# Merge a list of options containning different field. This is useful to
|
||
# separate the merge & apply fields from the interface.
|
||
mergeOptionDecls = opts:
|
||
if opts == [] then {}
|
||
else if length opts == 1 then
|
||
let opt = head opts; in
|
||
if opt ? options then
|
||
opt // { options = toList opt.options; }
|
||
else
|
||
opt
|
||
else
|
||
fold (opt1: opt2:
|
||
lib.addErrorContext "opt1 = ${lib.showVal opt1}\nopt2 = ${lib.showVal opt2}" (
|
||
# You cannot merge if two options have the same field.
|
||
assert opt1 ? default -> ! opt2 ? default;
|
||
assert opt1 ? example -> ! opt2 ? example;
|
||
assert opt1 ? description -> ! opt2 ? description;
|
||
assert opt1 ? merge -> ! opt2 ? merge;
|
||
assert opt1 ? apply -> ! opt2 ? apply;
|
||
assert opt1 ? type -> ! opt2 ? type;
|
||
opt1 // opt2
|
||
// optionalAttrs (opt1 ? options || opt2 ? options) {
|
||
options =
|
||
(toList (opt1.options or []))
|
||
++ (toList (opt2.options or []));
|
||
}
|
||
// optionalAttrs (opt1 ? extraConfigs || opt2 ? extraConfigs) {
|
||
extraConfigs = opt1.extraConfigs or [] ++ opt2.extraConfigs or [];
|
||
}
|
||
// optionalAttrs (opt1 ? extraArgs || opt2 ? extraArgs) {
|
||
extraArgs = opt1.extraArgs or {} // opt2.extraArgs or {};
|
||
}
|
||
// optionalAttrs (opt1 ? individualExtraArgs || opt2 ? individualExtraArgs) {
|
||
individualExtraArgs = zipAttrsWith (name: values:
|
||
if length values == 1 then head values else (head values // (head (tail values)))
|
||
) [ (opt1.individualExtraArgs or {}) (opt2.individualExtraArgs or {}) ];
|
||
}
|
||
)) {} opts;
|
||
|
||
|
||
# !!! This function will be removed because this can be done with the
|
||
# multiple option declarations.
|
||
addDefaultOptionValues = defs: opts: opts //
|
||
builtins.listToAttrs (map (defName:
|
||
{ name = defName;
|
||
value =
|
||
let
|
||
defValue = builtins.getAttr defName defs;
|
||
optValue = builtins.getAttr defName opts;
|
||
in
|
||
if typeOf defValue == "option"
|
||
then
|
||
# `defValue' is an option.
|
||
if hasAttr defName opts
|
||
then builtins.getAttr defName opts
|
||
else defValue.default
|
||
else
|
||
# `defValue' is an attribute set containing options.
|
||
# So recurse.
|
||
if hasAttr defName opts && isAttrs optValue
|
||
then addDefaultOptionValues defValue optValue
|
||
else addDefaultOptionValues defValue {};
|
||
}
|
||
) (attrNames defs));
|
||
|
||
mergeDefaultOption = list:
|
||
if length list == 1 then head list
|
||
else if all builtins.isFunction list then x: mergeDefaultOption (map (f: f x) list)
|
||
else if all isList list then concatLists list
|
||
else if all isAttrs list then fold lib.mergeAttrs {} list
|
||
else if all builtins.isBool list then fold lib.or false list
|
||
else if all builtins.isString list then lib.concatStrings list
|
||
else if all builtins.isInt list && all (x: x == head list) list
|
||
then head list
|
||
else throw "Cannot merge values.";
|
||
|
||
mergeTypedOption = typeName: predicate: merge: list:
|
||
if all predicate list then merge list
|
||
else throw "Expect a ${typeName}.";
|
||
|
||
mergeEnableOption = mergeTypedOption "boolean"
|
||
(x: true == x || false == x) (fold lib.or false);
|
||
|
||
mergeListOption = mergeTypedOption "list" isList concatLists;
|
||
|
||
mergeStringOption = mergeTypedOption "string"
|
||
(x: if builtins ? isString then builtins.isString x else x + "")
|
||
lib.concatStrings;
|
||
|
||
mergeOneOption = list:
|
||
if list == [] then abort "This case should never happen."
|
||
else if length list != 1 then throw "Multiple definitions. Only one is allowed for this option."
|
||
else head list;
|
||
|
||
|
||
fixableMergeFun = merge: f: config:
|
||
merge (
|
||
# generate the list of option sets.
|
||
f config
|
||
);
|
||
|
||
fixableMergeModules = merge: initModules: {...}@args: config:
|
||
fixableMergeFun merge (config:
|
||
lib.moduleClosure initModules (args // { inherit config; })
|
||
) config;
|
||
|
||
|
||
fixableDefinitionsOf = initModules: {...}@args:
|
||
fixableMergeModules (modules: (lib.moduleMerge "" modules).config) initModules args;
|
||
|
||
fixableDeclarationsOf = initModules: {...}@args:
|
||
fixableMergeModules (modules: (lib.moduleMerge "" modules).options) initModules args;
|
||
|
||
definitionsOf = initModules: {...}@args:
|
||
(lib.fix (module:
|
||
fixableMergeModules (lib.moduleMerge "") initModules args module.config
|
||
)).config;
|
||
|
||
declarationsOf = initModules: {...}@args:
|
||
(lib.fix (module:
|
||
fixableMergeModules (lib.moduleMerge "") initModules args module.config
|
||
)).options;
|
||
|
||
|
||
# Generate documentation template from the list of option declaration like
|
||
# the set generated with filterOptionSets.
|
||
optionAttrSetToDocList = ignore: newOptionAttrSetToDocList;
|
||
newOptionAttrSetToDocList = attrs:
|
||
let options = collect isOption attrs; in
|
||
fold (opt: rest:
|
||
let
|
||
docOption = {
|
||
inherit (opt) name;
|
||
description = if opt ? description then opt.description else
|
||
throw "Option ${opt.name}: No description.";
|
||
|
||
declarations = map (x: toString x.source) opt.declarations;
|
||
#definitions = map (x: toString x.source) opt.definitions;
|
||
}
|
||
// optionalAttrs (opt ? example) { example = scrubOptionValue opt.example; }
|
||
// optionalAttrs (opt ? default) { default = scrubOptionValue opt.default; }
|
||
// optionalAttrs (opt ? defaultText) { default = opt.defaultText; };
|
||
|
||
subOptions =
|
||
if opt ? options then
|
||
newOptionAttrSetToDocList opt.options
|
||
else
|
||
[];
|
||
in
|
||
[ docOption ] ++ subOptions ++ rest
|
||
) [] options;
|
||
|
||
|
||
/* This function recursively removes all derivation attributes from
|
||
`x' except for the `name' attribute. This is to make the
|
||
generation of `options.xml' much more efficient: the XML
|
||
representation of derivations is very large (on the order of
|
||
megabytes) and is not actually used by the manual generator. */
|
||
scrubOptionValue = x:
|
||
if isDerivation x then { type = "derivation"; drvPath = x.name; outPath = x.name; name = x.name; }
|
||
else if isList x then map scrubOptionValue x
|
||
else if isAttrs x then mapAttrs (n: v: scrubOptionValue v) (removeAttrs x ["_args"])
|
||
else x;
|
||
|
||
|
||
/* For use in the ‘example’ option attribute. It causes the given
|
||
text to be included verbatim in documentation. This is necessary
|
||
for example values that are not simple values, e.g.,
|
||
functions. */
|
||
literalExample = text: { _type = "literalExample"; inherit text; };
|
||
|
||
|
||
}
|