nixos/doc: render option values using `lib.generators.toPretty`

Render un`_type`d defaults and examples as `literalExpression`s using
`lib.generators.toPretty` so that consumers don't have to reinvent Nix
pretty-printing. `renderOptionValue` is kept internal for now intentionally.

Make `toPretty` print floats as valid Nix values (without a tilde).

Get rid of the now-obsolete `substSpecial` function.

Move towards disallowing evaluation of packages in the manual by
raising a warning on `pkgs.foo.{outPath,drvPath}`; later, this should
throw an error. Instead, module authors should use `literalExpression`
and `mkPackageOption`.

1 files changed, 1 insertions, 18 deletions

diff --git a/nixos/lib/make-options-doc/default.nix b/nixos/lib/make-options-doc/default.nix
index 694512115d40a..dea3eec5bd6d7 100644
--- a/nixos/lib/make-options-doc/default.nix
+++ b/nixos/lib/make-options-doc/default.nix
@@ -26,7 +26,7 @@
   # If you include more than one option list into a document, you need to
   # provide different ids.
 , variablelistId ? "configuration-variable-list"
-  # Strig to prefix to the option XML/HTML id attributes.
+  # String to prefix to the option XML/HTML id attributes.
 , optionIdPrefix ? "opt-"
 , revision ? "" # Specify revision for the options
 # a set of options the docs we are generating will be merged into, as if by recursiveUpdate.
@@ -45,28 +45,11 @@
 }:
 
 let
-  # Make a value safe for JSON. Functions are replaced by the string "<function>",
-  # derivations are replaced with an attrset
-  # { _type = "derivation"; name = <name of that derivation>; }.
-  # We need to handle derivations specially because consumers want to know about them,
-  # but we can't easily use the type,name subset of keys (since type is often used as
-  # a module option and might cause confusion). Use _type,name instead to the same
-  # effect, since _type is already used by the module system.
-  substSpecial = x:
-    if lib.isDerivation x then { _type = "derivation"; name = x.name; }
-    else if builtins.isAttrs x then lib.mapAttrs (name: substSpecial) x
-    else if builtins.isList x then map substSpecial x
-    else if lib.isFunction x then "<function>"
-    else x;
-
   rawOpts = lib.optionAttrSetToDocList options;
   transformedOpts = map transformOptions rawOpts;
   filteredOpts = lib.filter (opt: opt.visible && !opt.internal) transformedOpts;
   optionsList = lib.flip map filteredOpts
    (opt: opt
-    // lib.optionalAttrs (opt ? example) { example = substSpecial opt.example; }
-    // lib.optionalAttrs (opt ? default) { default = substSpecial opt.default; }
-    // lib.optionalAttrs (opt ? type) { type = substSpecial opt.type; }
     // lib.optionalAttrs (opt ? relatedPackages && opt.relatedPackages != []) { relatedPackages = genRelatedPackages opt.relatedPackages opt.name; }
    );