initial: packwiz → simple-mod-sync manifest converter

Reads packwiz pack (pack.toml + index.toml + per-file .pw.toml) and
emits a simple-mod-sync sync_version=3 manifest. Drops server-only
mods, skips CurseForge metadata-mode entries with a warning, maps
content type from the parent directory of each metafile.

Optional --bundle-non-mods zips config/, options.txt etc into one
archive served as a 'packed' entry — covers the gap where simple-mod-sync
only ships zip-extractable content for non-mods.

15 tests, includes integration against upstream packwiz-example-pack.

tests/fixture-pack/config/voicechat-client.properties

@@ -0,0 +1,2 @@
+voice_chat_volume=0.8
+microphone_amplification=1.0

tests/fixture-pack/index.toml

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+hash-format = "sha256"
+
+[[files]]
+file = "mods/sodium.pw.toml"
+hash = "0000000000000000000000000000000000000000000000000000000000000000"
+metafile = true
+
+[[files]]
+file = "mods/fabric-api.pw.toml"
+hash = "0000000000000000000000000000000000000000000000000000000000000000"
+metafile = true
+
+[[files]]
+file = "mods/server-side-tool.pw.toml"
+hash = "0000000000000000000000000000000000000000000000000000000000000000"
+metafile = true
+
+[[files]]
+file = "mods/cf-only-mod.pw.toml"
+hash = "0000000000000000000000000000000000000000000000000000000000000000"
+metafile = true
+
+[[files]]
+file = "resourcepacks/branding.pw.toml"
+hash = "0000000000000000000000000000000000000000000000000000000000000000"
+metafile = true
+
+[[files]]
+file = "shaderpacks/iris.pw.toml"
+hash = "0000000000000000000000000000000000000000000000000000000000000000"
+metafile = true
+
+[[files]]
+file = "config/voicechat-client.properties"
+hash = "1111111111111111111111111111111111111111111111111111111111111111"
+
+[[files]]
+file = "options.txt"
+hash = "2222222222222222222222222222222222222222222222222222222222222222"

tests/fixture-pack/mods/cf-only-mod.pw.toml

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+name = "CF Only Mod"
+filename = "cfmod-1.0.jar"
+side = "both"
+
+[download]
+hash-format = "murmur2"
+hash = "1234567"
+mode = "metadata:curseforge"
+
+[update]
+[update.curseforge]
+project-id = 12345
+file-id = 67890

tests/fixture-pack/mods/fabric-api.pw.toml

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+name = "Fabric API"
+filename = "fabric-api-0.110.5+1.21.1.jar"
+side = "both"
+
+[download]
+url = "https://cdn.modrinth.com/data/P7dR8mSH/versions/4OZL6q6h/fabric-api-0.110.5%2B1.21.1.jar"
+hash-format = "sha1"
+hash = "1234560000000000000000000000000000000000"

tests/fixture-pack/mods/server-side-tool.pw.toml

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+name = "Server Side Tool"
+filename = "spark-1.10.55-fabric.jar"
+side = "server"
+
+[download]
+url = "https://example.com/spark.jar"
+hash-format = "sha1"
+hash = "9999990000000000000000000000000000000000"

tests/fixture-pack/mods/sodium.pw.toml

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+name = "Sodium"
+filename = "sodium-fabric-0.6.5+mc1.21.1.jar"
+side = "client"
+
+[download]
+url = "https://cdn.modrinth.com/data/AANobbMI/versions/EoNKHoLH/sodium-fabric-0.6.5%2Bmc1.21.1.jar"
+hash-format = "sha1"
+hash = "abcdef0000000000000000000000000000000000"
+
+[update]
+[update.modrinth]
+mod-id = "AANobbMI"
+version = "EoNKHoLH"

tests/fixture-pack/options.txt

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+fov:90
+renderDistance:12

tests/fixture-pack/pack.toml

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+name = "Test Pack"
+author = "tester"
+version = "0.1.0"
+pack-format = "packwiz:1.1.0"
+
+[index]
+file = "index.toml"
+hash-format = "sha256"
+hash = "0000000000000000000000000000000000000000000000000000000000000000"
+
+[versions]
+minecraft = "1.21.1"
+fabric = "0.16.5"

tests/fixture-pack/resourcepacks/branding.pw.toml

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+name = "Server Branding"
+filename = "automc-branding-0.3.zip"
+side = "client"
+
+[download]
+url = "https://example.com/automc-branding-0.3.zip"
+hash-format = "sha256"
+hash = "aaaa000000000000000000000000000000000000000000000000000000000000"

tests/fixture-pack/shaderpacks/iris.pw.toml

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+name = "Complementary Shaders"
+filename = "complementary-r5.5.zip"
+side = "client"
+
+[download]
+url = "https://example.com/complementary-r5.5.zip"
+hash-format = "sha256"
+hash = "bbbb000000000000000000000000000000000000000000000000000000000000"

tests/test_packwiz_to_sms.py

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+"""Unit tests for packwiz_to_sms.convert + CLI."""
+
+from __future__ import annotations
+
+import json
+import subprocess
+import sys
+import zipfile
+from pathlib import Path
+
+import pytest
+
+
+ROOT = Path(__file__).resolve().parent.parent
+FIXTURE = Path(__file__).resolve().parent / "fixture-pack"
+SCRIPT = ROOT / "packwiz_to_sms.py"
+
+sys.path.insert(0, str(ROOT))
+import packwiz_to_sms as p2s  # noqa: E402
+
+
+def _by_name(sync: list[dict]) -> dict[str, dict]:
+    return {e["name"]: e for e in sync}
+
+
+def test_convert_emits_client_and_both_only() -> None:
+    r = p2s.convert(FIXTURE)
+    names = {e["name"] for e in r.manifest["sync"]}
+    # client + both kept
+    assert "Sodium" in names
+    assert "Fabric API" in names
+    # server-only dropped
+    assert "Server Side Tool" not in names
+    # CurseForge metadata-mode dropped (no URL)
+    assert "CF Only Mod" not in names
+    # resourcepack + shader kept
+    assert "Server Branding" in names
+    assert "Complementary Shaders" in names
+
+
+def test_convert_skip_reasons() -> None:
+    r = p2s.convert(FIXTURE)
+    assert "Server Side Tool" in r.skipped_server_only
+    assert "CF Only Mod" in r.skipped_no_url
+    assert r.skipped_unknown_type == []
+
+
+def test_convert_content_types() -> None:
+    r = p2s.convert(FIXTURE)
+    entries = _by_name(r.manifest["sync"])
+    assert entries["Sodium"]["type"] == "mod"
+    assert entries["Fabric API"]["type"] == "mod"
+    assert entries["Server Branding"]["type"] == "resourcepack"
+    assert entries["Complementary Shaders"]["type"] == "shader"
+
+
+def test_convert_url_preserved_verbatim() -> None:
+    r = p2s.convert(FIXTURE)
+    sodium = _by_name(r.manifest["sync"])["Sodium"]
+    assert sodium["url"] == (
+        "https://cdn.modrinth.com/data/AANobbMI/versions/EoNKHoLH/"
+        "sodium-fabric-0.6.5%2Bmc1.21.1.jar"
+    )
+
+
+def test_convert_version_extracted_from_filename() -> None:
+    r = p2s.convert(FIXTURE)
+    entries = _by_name(r.manifest["sync"])
+    assert entries["Sodium"]["version"] == "0.6.5+mc1.21.1"
+    assert entries["Fabric API"]["version"] == "0.110.5+1.21.1"
+    # Zip artifacts (resourcepacks, shaders) — same extractor handles them.
+    assert entries["Server Branding"]["version"] == "0.3"
+    assert entries["Complementary Shaders"]["version"] == "r5.5"
+
+
+def test_convert_lists_non_mod_files() -> None:
+    r = p2s.convert(FIXTURE)
+    files = {str(p) for p in r.non_mod_files}
+    assert "config/voicechat-client.properties" in files
+    assert "options.txt" in files
+
+
+def test_convert_top_level_shape() -> None:
+    r = p2s.convert(FIXTURE)
+    assert r.manifest["sync_version"] == 3
+    assert isinstance(r.manifest["sync"], list)
+    assert r.manifest["_generator"]["tool"] == "packwiz-to-sms"
+    assert r.manifest["_generator"]["pack_name"] == "Test Pack"
+    assert r.manifest["_generator"]["pack_version"] == "0.1.0"
+
+
+def test_bundle_non_mods(tmp_path: Path) -> None:
+    r = p2s.convert(FIXTURE)
+    out = tmp_path / "overrides.zip"
+    p2s.bundle_non_mods(FIXTURE, r.non_mod_files, out)
+    with zipfile.ZipFile(out) as zf:
+        names = set(zf.namelist())
+    assert "config/voicechat-client.properties" in names
+    assert "options.txt" in names
+
+
+def test_bundle_entry_appended() -> None:
+    r = p2s.convert(FIXTURE)
+    n_before = len(r.manifest["sync"])
+    p2s.add_bundle_entry(r.manifest, "https://example.com/overrides.zip", "0.1.0")
+    assert len(r.manifest["sync"]) == n_before + 1
+    bundle = r.manifest["sync"][-1]
+    assert bundle["type"] == "packed"
+    assert bundle["directory"] == "."
+    assert bundle["url"] == "https://example.com/overrides.zip"
+
+
+def test_cli_writes_to_stdout(tmp_path: Path) -> None:
+    proc = subprocess.run(
+        [sys.executable, str(SCRIPT), str(FIXTURE), "--quiet"],
+        capture_output=True, text=True, check=True,
+    )
+    payload = json.loads(proc.stdout)
+    assert payload["sync_version"] == 3
+    assert any(e["name"] == "Sodium" for e in payload["sync"])
+
+
+def test_cli_writes_to_output_flag(tmp_path: Path) -> None:
+    out = tmp_path / "manifest.json"
+    subprocess.run(
+        [sys.executable, str(SCRIPT), str(FIXTURE), "--quiet", "-o", str(out)],
+        check=True,
+    )
+    payload = json.loads(out.read_text())
+    assert payload["sync_version"] == 3
+
+
+def test_cli_bundle_requires_url(tmp_path: Path) -> None:
+    proc = subprocess.run(
+        [sys.executable, str(SCRIPT), str(FIXTURE),
+         "--bundle-non-mods", str(tmp_path / "x.zip"), "--quiet"],
+        capture_output=True, text=True,
+    )
+    assert proc.returncode == 2
+    assert "--bundle-url" in proc.stderr
+
+
+def test_cli_full_bundle_pipeline(tmp_path: Path) -> None:
+    bundle = tmp_path / "overrides.zip"
+    out = tmp_path / "manifest.json"
+    subprocess.run(
+        [sys.executable, str(SCRIPT), str(FIXTURE), "--quiet",
+         "-o", str(out),
+         "--bundle-non-mods", str(bundle),
+         "--bundle-url", "https://example.com/overrides.zip"],
+        check=True,
+    )
+    payload = json.loads(out.read_text())
+    bundle_entry = next(
+        (e for e in payload["sync"] if e.get("type") == "packed"), None
+    )
+    assert bundle_entry is not None
+    assert bundle_entry["url"] == "https://example.com/overrides.zip"
+    assert bundle.is_file()
+
+
+def test_cli_missing_pack_toml(tmp_path: Path) -> None:
+    proc = subprocess.run(
+        [sys.executable, str(SCRIPT), str(tmp_path), "--quiet"],
+        capture_output=True, text=True,
+    )
+    assert proc.returncode == 2
+    assert "pack.toml" in proc.stderr
+
+
+def test_convert_against_real_packwiz_example_pack(tmp_path: Path) -> None:
+    """Integration: clone the upstream packwiz-example-pack and convert it.
+
+    Skipped if no network / git unavailable. Verifies the tool works on
+    a real pack, not just our hand-rolled fixture.
+    """
+    pack_root = tmp_path / "example-pack"
+    try:
+        subprocess.run(
+            ["git", "clone", "--depth", "1", "--branch", "v1",
+             "https://github.com/packwiz/packwiz-example-pack.git",
+             str(pack_root)],
+            check=True, capture_output=True, timeout=30,
+        )
+    except (subprocess.CalledProcessError, subprocess.TimeoutExpired, FileNotFoundError):
+        pytest.skip("network/git unavailable")
+
+    r = p2s.convert(pack_root)
+    assert r.manifest["sync_version"] == 3
+    # Example pack has at least two mods we recognize
+    names = {e["name"] for e in r.manifest["sync"]}
+    assert any("Borderless" in n for n in names)
+    # All entries have a URL
+    assert all(e.get("url") for e in r.manifest["sync"])