Cross-module inlining copies Enum.Member references into the importer: "enum member X.Y not found in enums table" #10417

Found by the package audit (compiling real npm packages from source instead of Perry's native bindings) on
Perry e6dcb62 (v0.5.1587), Linux x64. When an exported function or class method reads a TypeScript enum member,
cross-module inlining copies the body into the importing module. That module's enum table has no such enum, so codegen
fails with enum member CharacterCode.Lt not found in enums table.

Reproduction

utils.ts:

enum CharacterCode { LowerA = 97, LowerZ = 122, Lt = 60 }   // `const enum` and `export enum` fail the same way
export function isHtml(str: string): boolean {
  const c = str.charCodeAt(1);
  return str.charCodeAt(0) === CharacterCode.Lt && c >= CharacterCode.LowerA && c <= CharacterCode.LowerZ;
}

main.ts:

import { isHtml } from "./utils.ts";
console.log(isHtml("<div>"), isHtml("hello"));

package.json: {"type":"module"}

perry compile main.ts -o main && ./main

Expected (Node 26.5.1)

Node 26.5.1 cannot run enum in strip-only mode (ERR_UNSUPPORTED_TYPESCRIPT_SYNTAX: TypeScript enum is not supported in strip-only mode). The files were therefore transpiled with TypeScript 5.8.2 transpileModule and the output was run
under Node 26.5.1:

true false

Actual (Perry)

Same result with and without PERRY_NO_AUTO_OPTIMIZE=1:

Error compiling module 'main.ts' (.../main.ts) with --backend llvm: lowering specialized entry for function '__perry_xmod_inline_1_isHtml': lowering body of '__perry_xmod_inline_1_isHtml': perry-codegen: enum member CharacterCode.Lt not found in enums table

✗ ENTRY MODULE FAILED TO COMPILE — REFUSING TO LINK

Impact

• cheerio 1.2.0 ships src/*.ts, and Perry compiles that source instead of dist/. src/utils.ts:63 declares
  const enum CharacterCode, and isHtml (src/utils.ts:82-96) reads it. src/load.ts and
  src/api/manipulation.ts import isHtml, so both fail with
  lowering body of '__perry_xmod_inline_11_isHtml': enum member CharacterCode.LowerA not found in enums table.
  Workaround: hide node_modules/cheerio/src so Perry compiles dist/esm.
• This likely affects any TS-source package (compiled via compilePackages) or multi-file TS app where a small exported
  helper or method reads an enum it does not re-export under the same name.

Notes

Results (compiled with PERRY_NO_AUTO_OPTIMIZE=1; the plain-enum and method variants also fail in auto mode):

• Cause (verified by reading the code; the fix direction is inferred): Expr::EnumMember { enum_name, member_name }
  names the enum as written in the source module. Codegen resolves it through ctx.enums
  (crates/perry-codegen/src/expr/bigint_set.rs:573-583). That table holds only the current module's own enums plus
  opts.imported_enums, keyed by the importer's local binding name (crates/perry-codegen/src/codegen/mod.rs:559-579).
  The cross-module safety checks reject FuncRef, GlobalGet, NativeModuleRef, and similar nodes, but they do not
  reject EnumMember, so it falls through to the generic child walk. Affected checks:

  • cross_function_expr_is_safe: free-function graphs, crates/perry-transform/src/inline/cross_module.rs:350-406
  • is_cross_module_safe: methods, cross_module.rs:8-40, used at :1017
  • is_cross_module_safe_with_externs: cross_module.rs:1146-1170, used at :1085

  No file in crates/perry-transform/src/inline/ mentions EnumMember. Possible fixes: reject EnumMember in the
  three checks, or fold members to literals (numeric or string) before harvesting candidates.

• Closed issues about imported enums in other positions: codegen: imported enum member reads undefined in array/object/template/builtin-arg positions #6879 (imported enum member reads undefined in
  array/object/template positions), web target: imported Key const enum values reach the FFI bridge as undefined #1991 (web target const enum). Neither covers inlining.