fix(codegen): #138 — link imported enum constructors into codegen

[hyperpolymath]

Closes #138

Note: #138 itself was joint-closed (2026-05-18) when the front-end
seeded-builtins band-aid was removed. That removal correctly routed
Some/None/Ok/Err through the module path so check passes — but it
exposed a codegen regression that this PR fixes. Verified at HEAD
58dc2a0.

Symptom

A module that imports prelude's Option/Result and applies their
constructors type-checks but fails to compile — the WASM backend raises
UnboundVariable "...Some". This blocked the stdlib option/result
layer (and downstream consumers) from producing a runnable artifact.

Root cause

Codegen learns constructor tags only from TopType decls. Two import
paths dropped imported types before they reached that registration:

• Core-Wasm Codegen.gen_imports — the path the default compile uses.
  It feeds the original (un-flattened) prog to generate_module and
  resolved imports natively, but wired up only TopFn (→ wasm import) and
  TopConst (→ global); imported types were silently dropped, so
  variant_tags had no Some → UnboundVariable. This is the path the
  reported failure hits.
• Module_loader.flatten_imports — used by the prog_decls-iterating
  backends (Deno / JS / Julia / C / Rust / …). It carried only TopFn/
  TopConst.

(The task brief pointed at flatten_imports; in practice the reported
compile failure flows through gen_imports — empirically, before this PR
the Deno/JS/Julia/C/Rust backends already compiled the consumer; only the
WASM backend was broken. Both sites are fixed for completeness.)

Fix

1. Codegen.gen_imports now registers the constructor tags / struct
   layouts of imported public types, reusing gen_decl's local-type
   registration so imported and local types share exactly one code path.
2. Module_loader.flatten_imports now inlines imported public TopType
   decls — a separate namespace from fn/const (own dedup table, so a
   local fn Foo can't suppress an imported type Foo), local-wins,
   deduped across paths, and ordered before consumers so the
   single-pass codegen sees a type before any function that uses it.

Selection: use M::{..} carries a type when the list names the type or
any of its constructors (so use prelude::{Some} works without naming
Option); use M / use M::* carry all public types.

Scope: directly-imported constructors lower on every backend.
Transitive re-export (a module re-exposing names it itself imported)
stays unimplemented — noted in docs/history/MODULE-SYSTEM-PROGRESS.md.

Verify — before / after

Minimal consumer.affine (use prelude::{Option, Some, None} + Some(x)/None):

# BEFORE (HEAD 58dc2a0)
$ affinescript check   consumer.affine   # Type checking passed
$ affinescript compile consumer.affine   # Code generation error:
                                         #   (Codegen.UnboundVariable
                                         #    "Function or variable not found: Some")

# AFTER
$ affinescript check   consumer.affine            # Type checking passed
$ affinescript compile -o consumer.wasm c.affine  # Compiled -> consumer.wasm (WASM)

Emitted WASM is valid and runtime-correct (via node WebAssembly):
wrap(5) → boxed Some (tag 0, payload 5); empty() → None (tag 1);
Ok/Err tags 0/1. Module imports only wasi_snapshot_preview1.fd_write
— constructors are compiled inline, no spurious imports.

All-backend matrix on the consumer (before → after):

backend	before	after
wasm (default)	FAIL UnboundVariable "Some"	OK
deno.js / jl / c / rs / js / cjs	OK	OK

Tests

• New Wasm-path regression test cross-module constructor linking, Wasm (#138)
  in test/test_stdlib_aot.ml — the counterpart to the test: multi-module integration test using several stdlib modules together #137 Deno-path
  integration. Feeds the imported-constructor decl shape to all three
  variant_tags consumers (with-arg construction, zero-arg, constructor
  patterns).
• dune test: 458 tests, all green (incl. ci: add stdlib-wide AOT compile-smoke gate #136 AOT smoke over 34 stdlib
  files and test: multi-module integration test using several stdlib modules together #137 integration — no regression).
• dune runtest conformance: green.

Out of scope (do not conflate with #138)

Pre-existing core-Wasm gaps that reproduce with purely local enums and
are independent of cross-module linking:

• stdlib/option.affine / result.affine → UnsupportedFeature "Only variable and wildcard patterns supported in tuple patterns". With this
  PR they get past the cleanup: remove b895374 seeded Some/None/Ok/Err builtins band-aid #138 UnboundVariable and reach this separate
  tuple-pattern codegen gap.
• Mixed-representation match of a zero-arg variant (None) against a
  constructor-with-args arm returns the wrong value at runtime — reproduces
  with a local Opt = Som(Int) | Non.

🤖 Generated with Claude Code

https://claude.ai/code/session_01Lz7pRcec2Z3tVtaAhvB3M8

---

Generated by Claude Code

[github-actions]

🔍 Hypatia Security Scan

Findings: 45 issues detected

Severity	Count
🔴 Critical	2
🟠 High	27
🟡 Medium	16

⚠️ Action Required: Critical security issues found!

View findings

[
  {
    "reason": "Action denoland/setup-deno@v2 needs attention",
    "type": "unpinned_action",
    "file": "publish-jsr.yml",
    "action": "pin_sha",
    "rule_module": "workflow_audit",
    "severity": "medium"
  },
  {
    "reason": "Issue in scorecard-enforcer.yml",
    "type": "scorecard_publish_with_run_step",
    "file": "scorecard-enforcer.yml",
    "action": "split_scorecard_publish_job",
    "rule_module": "workflow_audit",
    "severity": "high"
  },
  {
    "reason": "Issue in instant-sync.yml",
    "type": "secret_action_without_presence_gate",
    "file": "instant-sync.yml",
    "action": "peter-evans/repository-dispatch",
    "rule_module": "workflow_audit",
    "severity": "high"
  },
  {
    "reason": "Shell execution -- validate input before passing to shell (1 occurrences, CWE-78)",
    "type": "js_exec_sync",
    "file": "/home/runner/work/affinescript/affinescript/packages/affinescript-cli/mod.js",
    "action": "flag",
    "rule_module": "code_safety",
    "severity": "high"
  },
  {
    "reason": "Shell execution -- validate input before passing to shell (2 occurrences, CWE-78)",
    "type": "js_exec_sync",
    "file": "/home/runner/work/affinescript/affinescript/packages/affine-vscode/mod.js",
    "action": "flag",
    "rule_module": "code_safety",
    "severity": "high"
  },
  {
    "reason": "Shell execution -- validate input before passing to shell (1 occurrences, CWE-78)",
    "type": "js_exec_sync",
    "file": "/home/runner/work/affinescript/affinescript/affinescript-vite/src/affine-plugin-improved.js",
    "action": "flag",
    "rule_module": "code_safety",
    "severity": "high"
  },
  {
    "reason": "expect() in hot path (32 occurrences, CWE-754)",
    "type": "expect_in_hot_path",
    "file": "/home/runner/work/affinescript/affinescript/affinescriptiser/src/codegen/wasm_gen.rs",
    "action": "flag",
    "rule_module": "code_safety",
    "severity": "medium"
  },
  {
    "reason": "expect() in hot path (29 occurrences, CWE-754)",
    "type": "expect_in_hot_path",
    "file": "/home/runner/work/affinescript/affinescript/affinescriptiser/src/codegen/affine_gen.rs",
    "action": "flag",
    "rule_module": "code_safety",
    "severity": "medium"
  },
  {
    "reason": "unsafe block -- requires SAFETY comment (2 occurrences, CWE-676)",
    "type": "unsafe_block",
    "file": "/home/runner/work/affinescript/affinescript/runtime/src/panic.rs",
    "action": "flag",
    "rule_module": "code_safety",
    "severity": "medium"
  },
  {
    "reason": "unsafe block -- requires SAFETY comment (1 occurrences, CWE-676)",
    "type": "unsafe_block",
    "file": "/home/runner/work/affinescript/affinescript/runtime/src/alloc.rs",
    "action": "flag",
    "rule_module": "code_safety",
    "severity": "medium"
  }
]

Powered by Hypatia Neurosymbolic CI/CD Intelligence