implements EnumToStrEntry for nim ic

[ringabout]

type
  NodeKind = enum
    nkInt, nkStr, nkAdd

  Node = object
    case kind: NodeKind
    of nkInt: intVal: int
    of nkStr: strVal: string
    of nkAdd: left, right: ref Node

proc newInt(v: int): ref Node =
  new(result)
  result[] = Node(kind: nkInt, intVal: v)

let n = newInt(42)
echo n.intVal

gives unhandled exception: key not found: (module: 68, item: 3) [KeyError]

[Copilot]

Pull request overview

This PR fixes a crash in the NIF-based incremental compilation workflow (used by nim ic via the nim m / nim nifc steps) by properly persisting and reloading enum-to-string procs through the NIF index, and adds a regression test covering object variants.

Changes:

• Serialize EnumToStrEntry log entries into NIF (ast2nif.nim) so enum-to-string procs are recorded in module NIFs.
• Load EnumToStrEntry entries from the NIF index into the module graph and make getToStringProc fall back to key-based lookup (modulegraphs.nim).
• Add an ic regression test for enum discriminants in case objects (tests/ic/tenum.nim).

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
tests/ic/tenum.nim	Regression test reproducing the enum/case-object scenario that previously crashed under nim ic.
compiler/modulegraphs.nim	Adds a key-based cache for enum-to-string procs loaded from NIF and uses it as a fallback in getToStringProc.
compiler/ast2nif.nim	Implements writing EnumToStrEntry into the NIF output so it can be restored later.

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[ringabout]

There is an error error: passing argument 1 of ‘eqdestroy___OOZOOZsysma2dyk_u70’ from incompatible pointer type [-Wincompatible-pointer-types], I will solve it later

[ringabout]

There is an error error: passing argument 1 of ‘eqdestroy___OOZOOZsysma2dyk_u70’ from incompatible pointer type [-Wincompatible-pointer-types]

I find the cause of it => #25619
the element type of seqs is skipped by typekeys

[github-actions]

Thanks for your hard work on this PR!
The lines below are statistics of the Nim compiler built from a7e0065

Hint: mm: orc; opt: speed; options: -d:release
190128 lines; 11.770s; 802.941MiB peakmem