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Upgrading multidict 2 to 3

Breaking2.1.6 → 3.3.2Breaking4New3Changed1Fixed5Other2

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BreakingUpgrade verdict

4 breaking changes.

In plain terms
  • When you update a key, the new value takes the place of the last matching entry and any earlier duplicates are dropped; new keys are appended at the end.
  • Popping a key now removes just the first matching entry; a new popone() method is available.
  • Proxy objects can no longer be serialized with pickle.
  • Keys must now be strings; other key types are no longer accepted.
Must act Top 3 of 4 that need code or config changes

Requires Python >=3.4.1 from 3.3.2 (none stated before).

What you must change

Breaking4
Preserves order on multidict updates: the last entry is replaced and previous occurrences removed.
md[key] = valmd.update()
3.0.0GitHub ReleaseSummarizedView source
.pop() removes only the first occurrence, and .popone() is added.
.pop().popone()
3.0.0GitHub ReleaseSummarizedView source
Proxies are no longer picklable.
3.0.0GitHub ReleaseSummarizedView source
Forces keys to be str instances.
3.0.0GitHub ReleaseSummarizedView source

API changes

Generated by DepDelta from published Python source. Not mixed with prose notes.

  • removed: method MultiDict.clear() -> None
  • removed: method MultiDict.get(key: _S, default: Optional[_T]=…) -> _T
  • removed: method MultiDict.items() -> ItemsView[_S, _T]
  • removed: method MultiDict.keys() -> KeysView[_S]
  • removed: method MultiDict.pop(key: _S) -> _T | (key: _S, default: _T=…) -> _T
  • removed: method MultiDict.popitem() -> Tuple[_S, _T]
  • removed: method MultiDict.setdefault(key: _S, default: _T=…) -> _T
  • removed: method MultiDict.values() -> ValuesView[_T]
  • removed: method MultiDictProxy.get(key: _S, default: Optional[_T]=…) -> _T
  • removed: method MultiDictProxy.items() -> ItemsView[_S, _T]
  • removed: method MultiDictProxy.keys() -> KeysView[_S]
  • removed: method MultiDictProxy.values() -> ValuesView[_T]
  • changed: class CIMultiDict(MultiDict[_T], Generic[_T]) → class CIMultiDict(MultiDict[_T])
  • changed: class CIMultiDictProxy(MultiDictProxy[_T], Generic[_T]) → class CIMultiDictProxy(MultiDictProxy[_T])
  • changed: class MultiDict(MutableMapping[_S, _T], Generic[_T]) → class MultiDict(MutableMapping[_S, _T])
  • changed: class MultiDictProxy(Mapping[_S, _T], Generic[_T]) → class MultiDictProxy(Mapping[_S, _T])
  • added: function getversion(md: Union[MultiDict[_T], CIMultiDict[_T], MultiDictProxy[_T], CIMultiDictProxy[_T]]) -> int
  • added: method MultiDict.extend(dct: MultiDict[_T]) -> None | (map: Mapping[_S, _T]) -> None | (iterable: Iterable[Tuple[_S, _T]]) -> None
  • added: method MultiDict.popall(key: _S) -> List[_T] | (key: _S, default: _T=…) -> List[_T]
  • added: method MultiDict.popone(key: _S) -> _T | (key: _S, default: _T=…) -> _T