fix(dispatcher): deterministic shim creation + reliable subprocess execution

Dispatcher:
- Add _ensure_all_version_shims() to eagerly create versioned shims (3.7–3.15) at startup
- Ensure Windows shims are real .bat wrappers (not symlinks) with injected `--python X.Y`
- Fix source executable resolution to ONLY match base entrypoints (8pkg / omnipkg)
  and never chain versioned shims (prevents recursive wrapping bugs)
- Make shim generation idempotent with content validation + rewrite on drift
- Surface write failures instead of silently skipping (prevents phantom shim state)
- Normalize behavior across platforms (Windows .bat vs Unix symlinks)

Dispatcher (bugfixes):
- Prevent accidental matching of versioned shims as sources during install
- Fix stale shim scenarios when underlying executable path changes

Tests:
- Rewrite test_multiverse_healing to use registry-driven interpreter resolution
- Remove fragile context swapping / bootstrap logic
- Add robust subprocess execution layer with:
  - explicit env isolation
  - streamed output capture
  - clear launch failure diagnostics
- Fix Windows execution by properly handling `.bat` via `cmd /c`
- Standardize versioned command resolution (exe → bat → shim fallback)

Config:
- Fix Pygments constraints:
  - Python >=3.9 → >=2.20.0 (CVE fix)
  - Python <3.9 → >=2.17.2,<2.18.0 (last compatible series)

Result:
- Eliminates Windows shim flakiness and subprocess launch failures
- Removes recursive shim chaining bugs
- Makes multiverse test deterministic across platforms
- Ensures forward-compatible versioned entrypoints (3.7–3.15)

Modified:
  • src/omnipkg/core.py (+2/-1 lines)
  • src/omnipkg/dispatcher.py (+96/-33 lines)
  • pyproject.toml (+2/-2 lines)
  • src/tests/test_multiverse_healing.py (+249/-301 lines)

[gitship-generated]

Author: 1minds3t

pyproject.toml

@@ -45,9 +45,9 @@ dependencies = [
     "typer>=0.4.0",
     "rich>=10.0.0",
 
-    # Pygments - ReDoS CVE in AdlLexer, fixed in 2.20.0 (2.19.x is last for py37/py38)
+    # Pygments - ReDoS CVE in AdlLexer fixed in 2.20.0; 2.18+ require >=3.9, so py37/py38 stuck at 2.17.2
     "pygments>=2.20.0 ; python_version >= '3.9'",
-    "pygments>=2.19.0,<2.20.0 ; python_version < '3.9'",
+    "pygments>=2.17.2,<2.18.0 ; python_version < '3.9'",  # 2.18+ requires Python >=3.9
 
     # werkzeug - pinned to last available per Python, CVEs unresolved due to Python constraints
     # TODO: werkzeug-lts needed for py37/py38 to backport CVE-2026-27199, CVE-2026-21860, CVE-2025-66221

src/omnipkg/core.py

@@ -17659,4 +17659,5 @@ def is_cache_entry_stale(
 #   atexit.register(self.pypi_cache.flush)
 #
 # This ensures any dirty in-memory cache writes hit disk on clean exit
-# without blocking the hot path.
+# without blocking the hot path.# test
+# test

src/omnipkg/dispatcher.py

@@ -1635,6 +1635,85 @@ def _is_plausible_python_version(version: str) -> bool:
 
 
 
+def _ensure_all_version_shims(bin_dir: Path, debug_mode: bool = False) -> None:
+    """
+    Eagerly create versioned shims for Python 3.7–3.15 in bin_dir.
+
+    On Unix: symlinks (8pkg39 -> 8pkg, omnipkg311 -> omnipkg, etc.)
+    On Windows: .bat wrappers with injected --python X.Y, because .bat files
+                cannot be launched by subprocess without cmd /c — they need
+                actual file content, not symlinks.
+
+    This runs at every dispatcher startup so shims exist for ALL versions
+    including ones not yet adopted (e.g. 3.13 before its interpreter is
+    downloaded). The dispatcher's --python routing + healing takes over
+    when the interpreter is actually missing.
+    """
+    # Case-variant aliases for case-sensitive filesystems (Linux)
+    if sys.platform != "win32":
+        main_shim = bin_dir / "8pkg"
+        omni_shim = bin_dir / "omnipkg"
+        for alias, target in [("8PKG", main_shim), ("OMNIPKG", omni_shim)]:
+            p = bin_dir / alias
+            if (not p.exists() and not p.is_symlink()) and target.exists():
+                try:
+                    p.symlink_to(target.name)
+                except Exception:
+                    pass
+
+    for minor in range(7, 16):
+        ver = f"3.{minor}"
+        flat = f"3{minor}"
+        for base_name in ("8pkg", "omnipkg"):
+            if sys.platform == "win32":
+                # Find the real executable to delegate to.
+                # IMPORTANT: only match the bare entry point (8pkg.exe / omnipkg.exe),
+                # never a versioned shim like 8pkg310.bat — those are outputs, not sources.
+                src_exe = None
+                for ext in (".exe", ".bat", ".cmd", ""):
+                    candidate = bin_dir / f"{base_name}{ext}"
+                    # Exclude versioned shims (names contain a digit after the base)
+                    name_stem = candidate.stem  # e.g. "8pkg310" or "8pkg"
+                    if name_stem != base_name:
+                        continue
+                    if candidate.exists():
+                        src_exe = candidate
+                        break
+                if src_exe is None:
+                    if debug_mode:
+                        print(f"[DEBUG-DISPATCH] ⚠️  No src_exe for {base_name} in {bin_dir} — skipping {base_name}{flat}.bat", file=sys.stderr)
+                    continue
+                bat_path = bin_dir / f"{base_name}{flat}.bat"
+                bat_content = f'@echo off\r\n"{src_exe}" --python {ver} %*\r\n'
+                # Idempotency: skip only if existing content is already correct.
+                if bat_path.exists():
+                    try:
+                        existing = bat_path.read_text(encoding="ascii")
+                        if existing == bat_content:
+                            continue  # already correct — truly idempotent
+                        # Content is stale (e.g. src_exe path changed) — rewrite below
+                        if debug_mode:
+                            print(f"[DEBUG-DISPATCH] 🔄 Stale .bat shim {bat_path.name} — rewriting", file=sys.stderr)
+                    except Exception:
+                        pass  # unreadable — fall through to overwrite
+                try:
+                    bat_path.write_text(bat_content, encoding="ascii")
+                    if debug_mode:
+                        print(f"[DEBUG-DISPATCH] ✅ Eager .bat shim: {bat_path.name}", file=sys.stderr)
+                except Exception as e:
+                    # Always surface write failures — silent skip here is the primary
+                    # reason shims appear to be created but are actually missing.
+                    print(f"[WARNING-DISPATCH] Could not write {bat_path.name}: {e}", file=sys.stderr)
+            else:
+                target = bin_dir / base_name
+                versioned = bin_dir / f"{base_name}{flat}"
+                if (not versioned.exists() and not versioned.is_symlink()) and target.exists():
+                    try:
+                        versioned.symlink_to(target.name)
+                    except Exception:
+                        pass
+
+
 def _ensure_native_shims() -> None:
     """
     Self-healing shim check for the native/primary Python.
@@ -1670,16 +1749,7 @@ def _ensure_native_shims() -> None:
 
     if shim_path.exists():
         # Still proactively create all versioned shims 3.7-3.15 if any are missing
-        main_shim = bin_dir / "8pkg"
-        omni_shim = bin_dir / "omnipkg"
-        for minor in range(7, 16):
-            for prefix, target in [("8pkg", main_shim), ("omnipkg", omni_shim)]:
-                versioned = bin_dir / f"{prefix}3{minor}"
-                if (not versioned.exists() and not versioned.is_symlink()) and target.exists():
-                    try:
-                        versioned.symlink_to(target.name)
-                    except Exception:
-                        pass
+        _ensure_all_version_shims(bin_dir, debug_mode)
         return  # already installed, nothing to do
 
     # Shim is missing — this is the native Python that adoption skipped.
@@ -1698,24 +1768,7 @@ def _ensure_native_shims() -> None:
     # Also immediately create the full range of versioned shims so 8pkg310 etc exist.
     # We do this here because the shim_path.exists() quick-exit branch won't run
     # on this first call since we just created the shim above.
-    main_shim = bin_dir / "8pkg"
-    omni_shim = bin_dir / "omnipkg"
-    # Case-variant aliases for case-sensitive filesystems (Linux)
-    for alias, target in [("8PKG", main_shim), ("OMNIPKG", omni_shim)]:
-        p = bin_dir / alias
-        if (not p.exists() and not p.is_symlink()) and target.exists():
-            try:
-                p.symlink_to(target.name)
-            except Exception:
-                pass
-    for minor in range(7, 16):
-        for prefix, target in [("8pkg", main_shim), ("omnipkg", omni_shim)]:
-            versioned = bin_dir / f"{prefix}3{minor}"
-            if (not versioned.exists() and not versioned.is_symlink()) and target.exists():
-                try:
-                    versioned.symlink_to(target.name)
-                except Exception:
-                    pass
+    _ensure_all_version_shims(bin_dir, debug_mode)
 
     # Call the canonical shim installer — handles Unix symlinks and Windows .bat
     interpreter_path = Path(sys.executable)
@@ -1769,6 +1822,9 @@ def install_versioned_entrypoints(
             src_bat = None
             for ext in (".exe", ".bat", ".cmd", ""):
                 candidate = bin_dir / f"{base_name}{ext}"
+                # Exclude versioned shims — only match the bare entry point.
+                if candidate.stem != base_name:
+                    continue
                 if candidate.exists():
                     src_bat = candidate
                     break
@@ -1781,16 +1837,23 @@ def install_versioned_entrypoints(
             _maj = flat[0]
             _min = flat[1:]
             _ver = f"{_maj}.{_min}"
+            bat_content = f'@echo off\r\n"{src_bat}" --python {_ver} %*\r\n'
+            # Idempotency: skip only if existing content is already correct.
+            if link_bat.exists():
+                try:
+                    existing = link_bat.read_text(encoding="ascii")
+                    if existing == bat_content:
+                        continue  # already correct
+                    if debug_mode:
+                        print(f"[DEBUG-DISPATCH] 🔄 Stale .bat shim {link_bat.name} — rewriting", file=sys.stderr)
+                except Exception:
+                    pass
             try:
-                # Inject --python X.Y as first arg so dispatcher version detection
-                # works even though sys.argv[0] will be "8pkg" not "8pkg310"
-                bat_content = f'@echo off\r\n"{src_bat}" --python {_ver} %*\r\n'
                 link_bat.write_text(bat_content, encoding="ascii")
                 if debug_mode:
                     print(f"[DEBUG-DISPATCH] ✅ Windows .bat shim: {link_bat} -> {src_bat.name} --python {_ver}", file=sys.stderr)
             except Exception as e:
-                if debug_mode:
-                    print(f"[DEBUG-DISPATCH] ⚠️  Could not create Windows shim {link_bat}: {e}", file=sys.stderr)
+                print(f"[WARNING-DISPATCH] Could not create Windows shim {link_bat.name}: {e}", file=sys.stderr)
         else:
             # Unix: relative symlink within same directory
             src = bin_dir / base_name