nixpkgs/pkgs/development/misc/resholve/resholve-utils.nix
Travis A. Everett a649cbca09 resholvePackage: extract util functions
Extract argument-handling utility functions to prepare for adding
resholveScript* functions.

This tracks upstream work, but I broke it up a little more semantically here
in case it aids review. See:
6aab748205
2021-09-27 16:01:09 +09:00

74 lines
2.8 KiB
Nix

{ lib, resholve, binlore }:
rec {
/* These functions break up the work of partially validating the
'solutions' attrset and massaging it into env/cli args.
Note: some of the left-most args do not *have* to be passed as
deep as they are, but I've done so to provide more error context
*/
# for brevity / line length
spaces = l: builtins.concatStringsSep " " l;
semicolons = l: builtins.concatStringsSep ";" l;
/* Throw a fit with dotted attr path context */
nope = path: msg:
throw "${builtins.concatStringsSep "." path}: ${msg}";
/* Special-case directive value representations by type */
makeDirective = solution: env: name: val:
if builtins.isInt val then builtins.toString val
else if builtins.isString val then name
else if true == val then name
else if false == val then "" # omit!
else if null == val then "" # omit!
else if builtins.isList val then "${name}:${semicolons val}"
else nope [ solution env name ] "unexpected type: ${builtins.typeOf val}";
/* Build fake/fix/keep directives from Nix types */
makeDirectives = solution: env: val:
lib.mapAttrsToList (makeDirective solution env) val;
/* Special-case value representation by type/name */
makeEnvVal = solution: env: val:
if env == "inputs" then lib.makeBinPath val
else if builtins.isString val then val
else if builtins.isList val then spaces val
else if builtins.isAttrs val then spaces (makeDirectives solution env val)
else nope [ solution env ] "unexpected type: ${builtins.typeOf val}";
/* Shell-format each env value */
shellEnv = solution: env: value:
lib.escapeShellArg (makeEnvVal solution env value);
/* Build a single ENV=val pair */
makeEnv = solution: env: value:
"RESHOLVE_${lib.toUpper env}=${shellEnv solution env value}";
/* Discard attrs claimed by makeArgs */
removeCliArgs = value:
removeAttrs value [ "scripts" "flags" ];
/* Verify required arguments are present */
validateSolution = { scripts, inputs, interpreter, ... }: true;
/* Pull out specific solution keys to build ENV=val pairs */
makeEnvs = solution: value:
spaces (lib.mapAttrsToList (makeEnv solution) (removeCliArgs value));
/* Pull out specific solution keys to build CLI argstring */
makeArgs = { flags ? [ ], scripts, ... }:
spaces (flags ++ scripts);
/* Build a single resholve invocation */
makeInvocation = solution: value:
if validateSolution value then
# we pass resholve a directory
"RESHOLVE_LORE=${binlore.collect { drvs = value.inputs; } } ${makeEnvs solution value} ${resholve}/bin/resholve --overwrite ${makeArgs value}"
else throw "invalid solution"; # shouldn't trigger for now
/* Build resholve invocation for each solution. */
makeCommands = solutions:
lib.mapAttrsToList makeInvocation solutions;
}