新しい iPhone の幅を足す前に、既存の分岐表を Gemini に書き出してもらいました

from google import genai
from google.genai import types
 
client = genai.Client(api_key="YOUR_API_KEY")
 
BRANCH_SCHEMA = {
    "type": "object",
    "properties": {
        "branches": {
            "type": "array",
            "items": {
                "type": "object",
                "properties": {
                    "file": {"type": "string"},
                    "line": {"type": "integer"},
                    "threshold": {"type": "integer"},
                    "comparison": {"type": "string", "enum": [">=", ">", "==", "<=", "<"]},
                    "value": {"type": "string"},
                },
                # 欠けたまま返させない。あとの検査が静かに壊れる
                "required": ["file", "line", "threshold", "comparison", "value"],
                "propertyOrdering": ["file", "line", "threshold", "comparison", "value"],
            },
        }
    },
    "required": ["branches"],
}
 
PROMPT = """次のソースから、画面幅で分岐している箇所だけを抽出してください。
- 行番号はソース先頭を 1 行目として数えます
- 幅以外の条件（OS バージョン・言語など）は対象外です
- 判断が付かない行は出力せず、そのまま省いてください
 
--- source: {name} ---
{source}
"""
 
def extract(name: str, source: str) -> dict:
    numbered = "\n".join(f"{i}: {l}" for i, l in enumerate(source.splitlines(), 1))
    res = client.models.generate_content(
        model="gemini-3.5-flash-lite",
        contents=PROMPT.format(name=name, source=numbered),
        config=types.GenerateContentConfig(
            response_mime_type="application/json",
            response_schema=BRANCH_SCHEMA,
            temperature=0,
        ),
    )
    return res.parsed  # {"branches": [...]}

# 既存のしきい値（ソース上の評価順）
BRANCHES = [
    (430, "proMax"), (428, "plus"), (414, "legacyPlus"),
    (393, "standardPro"), (390, "standard"), (0, "compact"),
]
 
# アプリが対象にしている画面幅（pt・縦持ち）
DEVICES = {
    "compact-375": 375, "mini-375": 375, "standard-390": 390,
    "standard-393": 393, "new-402": 402, "new-420": 420,
    "legacy-414": 414, "plus-428": 428, "proMax-430": 430, "new-440": 440,
}
 
# 設計上こうなってほしい割り当て（意図）
INTENT = {
    "compact-375": "compact", "mini-375": "compact", "standard-390": "standard",
    "standard-393": "standardPro", "new-402": "standard402", "new-420": "air420",
    "legacy-414": "legacyPlus", "plus-428": "plus", "proMax-430": "proMax",
    "new-440": "proMax440",
}
 
def resolve(width: int) -> str:
    for threshold, bucket in BRANCHES:
        if width >= threshold:
            return bucket
    return "unreachable"
 
mismatch = 0
for name, w in DEVICES.items():
    got, want = resolve(w), INTENT[name]
    if got != want:
        mismatch += 1
    print(f"{name:<14}{w:>6}  {got:<14}{want:<14}{'OK' if got == want else 'MISMATCH'}")
 
print(f"\ndevices: {len(DEVICES)}  mismatch: {mismatch}  ({mismatch / len(DEVICES) * 100:.0f}%)")

compact-375      375  compact       compact       OK
mini-375         375  compact       compact       OK
standard-390     390  standard      standard      OK
standard-393     393  standardPro   standardPro   OK
new-402          402  standardPro   standard402   MISMATCH
new-420          420  legacyPlus    air420        MISMATCH
legacy-414       414  legacyPlus    legacyPlus    OK
plus-428         428  plus          plus          OK
proMax-430       430  proMax        proMax        OK
new-440          440  proMax        proMax440     MISMATCH
 
devices: 10  mismatch: 3  (30%)

import json
 
branches = json.loads(payload)["branches"]  # 抽出結果をそのまま渡します
 
order_errors = []
for prev, cur in zip(branches, branches[1:]):
    if cur["threshold"] > prev["threshold"]:
        order_errors.append(
            f'{cur["file"]}:{cur["line"]} threshold {cur["threshold"]} '
            f'is above the earlier {prev["threshold"]} (unreachable)'
        )
 
for e in order_errors:
    print("ORDER:", e)
print(f"branches: {len(branches)}  order errors: {len(order_errors)}")

ORDER: DefineManager.h:43 threshold 430 is above the earlier 414 (unreachable)
branches: 4  order errors: 1