reportTypedDictNotRequiredAccess seems not works correctly.

[AiroPi]

Environment data

PyLance : v2021.10.1-pre.1

• Language Server version: v2021.10.1-pre.1
• OS and version: Windows 11 Professionnel Education version 21H2
• Python version (& distribution if applicable, e.g. Anaconda): Python 3.10.0

Expected behaviour

PyLance should know that we defined the key when creating the object, and nowhere after declaration we deleted any key.
Also, even if we add a check if the key exist there is an avert.

Actual behaviour

PyLance trigger the reportTypedDictNotRequiredAccess error even if it should not.

Logs

[Info  - 16:50:45] Pylance language server 2021.10.1-pre.1 (pyright d5878534) starting
[Info  - 16:50:45] Server root directory: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist
[Info  - 16:50:45] No configuration file found.
[Info  - 16:50:45] No pyproject.toml file found.
[Info  - 16:50:45] Setting pythonPath for service "test": "C:\Users\pierr\AppData\Local\Programs\Python\Python310\python.exe"
[Warn  - 16:50:45] stubPath c:\Users\pierr\Documents\programmation\git\test\typings is not a valid directory.
[Info  - 16:50:45] Assuming Python version 3.10
[Info  - 16:50:45] Assuming Python platform Windows
Search paths for c:\Users\pierr\Documents\programmation\git\test
  c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stdlib
  c:\Users\pierr\Documents\programmation\git\test
  c:\Users\pierr\Documents\programmation\git\test\typings
  c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stubs\...
  c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\bundled\stubs
  c:\Users\pierr\AppData\Local\Programs\Python\Python310\DLLs
  c:\Users\pierr\AppData\Local\Programs\Python\Python310\Lib
  c:\Users\pierr\AppData\Local\Programs\Python\Python310
  c:\Users\pierr\AppData\Roaming\Python\Python310\site-packages
  c:\Users\pierr\AppData\Local\Programs\Python\Python310\Lib\site-packages
[Info  - 16:50:46] Searching for source files
[Info  - 16:50:47] Found 1 source file
[FG] parsing: c:\Users\pierr\Documents\programmation\git\test\test.py (129ms)
[FG] parsing: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stdlib\builtins.pyi [fs read 68ms] (580ms)
[FG] binding: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stdlib\builtins.pyi (163ms)
[FG] binding: c:\Users\pierr\Documents\programmation\git\test\test.py (1ms)
[Info  - 16:50:47] Background analysis(1) root directory: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist
[Info  - 16:50:47] Background analysis(1) started
Background analysis message: setConfigOptions
Background analysis message: setImportResolver
Background analysis message: ensurePartialStubPackages
Background analysis message: setTrackedFiles
Background analysis message: markAllFilesDirty
Background analysis message: setFileOpened
Background analysis message: getDiagnosticsForRange
Background analysis message: analyze
[BG(1)] analyzing: c:\Users\pierr\Documents\programmation\git\test\test.py ...
[BG(1)]   parsing: c:\Users\pierr\Documents\programmation\git\test\test.py (211ms)
[BG(1)]   parsing: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stdlib\builtins.pyi [fs read 42ms] (532ms)
[Info  - 16:50:48] Indexer background runner(2) root directory: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist
[Info  - 16:50:48] Indexing(2) started
[BG(1)]   binding: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stdlib\builtins.pyi (134ms)
[BG(1)]   binding: c:\Users\pierr\Documents\programmation\git\test\test.py (1ms)
[BG(1)]   checking: c:\Users\pierr\Documents\programmation\git\test\test.py ...
[BG(1)]     parsing: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stdlib\typing.pyi [fs read 30ms] (222ms)
[BG(1)]     binding: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stdlib\typing.pyi (65ms)
[BG(1)]     parsing: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stdlib\_typeshed\__init__.pyi [fs read 44ms] (63ms)
[BG(1)]     binding: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stdlib\_typeshed\__init__.pyi (3ms)
[BG(1)]     parsing: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stdlib\types.pyi [fs read 30ms] (98ms)
[BG(1)]     binding: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stdlib\types.pyi (38ms)
[BG(1)]     parsing: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stdlib\typing_extensions.pyi [fs read 41ms] (78ms)
[BG(1)]     binding: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stdlib\typing_extensions.pyi (7ms)
[BG(1)]     parsing: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stdlib\abc.pyi [fs read 19ms] (21ms)
[BG(1)]     binding: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stdlib\abc.pyi (1ms)
[BG(1)]   checking: c:\Users\pierr\Documents\programmation\git\test\test.py (809ms)
[BG(1)] analyzing: c:\Users\pierr\Documents\programmation\git\test\test.py (1702ms)
Background analysis message: getSemanticTokens full
[BG(1)] getSemanticTokens full at c:\Users\pierr\Documents\programmation\git\test\test.py (86ms)
Background analysis message: getDiagnosticsForRange
Background analysis message: getSemanticTokens range
[BG(1)] getSemanticTokens range 0:0 - 17:0 at c:\Users\pierr\Documents\programmation\git\test\test.py (4ms)
Background analysis message: resumeAnalysis
[BG(1)] indexing: c:\Users\pierr\Documents\programmation\git\test\test.py [found 2] (1ms)
Indexing Done: c:\Users\pierr\Documents\programmation\git\test\test.py
[IDX(2)] index libraries c:\Users\pierr\Documents\programmation\git\test ...
[IDX(2)]   read stdlib indices (1082ms)
Background analysis message: getDiagnosticsForRange
Background analysis message: getDiagnosticsForRange
[IDX(2)]   scan packages [found 18 modules over 1 exec env] (2063ms)
[Info  - 16:50:52] [IDX(2)] Long operation: scan packages (2063ms)
[IDX(2)]   index execution environment c:\Users\pierr\Documents\programmation\git\test ...
[IDX(2)]     parsing: c:\Users\pierr\AppData\Local\Programs\Python\Python310\Lib\xml\__init__.py [fs read 0ms] (65ms)
[IDX(2)]     parsing: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stdlib\builtins.pyi [fs read 10ms] (224ms)
[IDX(2)]     binding: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stdlib\builtins.pyi (35ms)
[IDX(2)]     binding: c:\Users\pierr\AppData\Local\Programs\Python\Python310\Lib\xml\__init__.py (0ms)
[IDX(2)]     indexing: c:\Users\pierr\AppData\Local\Programs\Python\Python310\Lib\xml\__init__.py [found 0] (1ms)
[IDX(2)]     parsing: c:\Users\pierr\AppData\Local\Programs\Python\Python310\Lib\site-packages\pip\__init__.py [fs read 3ms] (4ms)
[IDX(2)]     binding: c:\Users\pierr\AppData\Local\Programs\Python\Python310\Lib\site-packages\pip\__init__.py (4ms)
[IDX(2)]     indexing: c:\Users\pierr\AppData\Local\Programs\Python\Python310\Lib\site-packages\pip\__init__.py ...
[IDX(2)]       parsing: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stdlib\typing.pyi [fs read 1ms] (69ms)
[IDX(2)]       binding: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stdlib\typing.pyi (6ms)
[IDX(2)]     indexing: c:\Users\pierr\AppData\Local\Programs\Python\Python310\Lib\site-packages\pip\__init__.py [found 4] (79ms)
[IDX(2)]     parsing: c:\Users\pierr\AppData\Local\Programs\Python\Python310\Lib\site-packages\pkg_resources\__init__.py [fs read 1ms] (193ms)
[IDX(2)]     binding: c:\Users\pierr\AppData\Local\Programs\Python\Python310\Lib\site-packages\pkg_resources\__init__.py (8ms)
[IDX(2)]     indexing: c:\Users\pierr\AppData\Local\Programs\Python\Python310\Lib\site-packages\pkg_resources\__init__.py ...
[IDX(2)]       parsing: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stdlib\pkgutil.pyi [fs read 27ms] (57ms)
[IDX(2)]       binding: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stdlib\pkgutil.pyi (2ms)
[IDX(2)]     indexing: c:\Users\pierr\AppData\Local\Programs\Python\Python310\Lib\site-packages\pkg_resources\__init__.py [found 71] (63ms)
[IDX(2)]     parsing: c:\Users\pierr\AppData\Local\Programs\Python\Python310\Lib\site-packages\setuptools\__init__.py [fs read 0ms] (37ms)
[IDX(2)]     binding: c:\Users\pierr\AppData\Local\Programs\Python\Python310\Lib\site-packages\setuptools\__init__.py (3ms)
[IDX(2)]     indexing: c:\Users\pierr\AppData\Local\Programs\Python\Python310\Lib\site-packages\setuptools\__init__.py ...
[IDX(2)]       parsing: c:\Users\pierr\AppData\Local\Programs\Python\Python310\Lib\site-packages\setuptools\_deprecation_warning.py [fs read 4ms] (9ms)
[IDX(2)]       binding: c:\Users\pierr\AppData\Local\Programs\Python\Python310\Lib\site-packages\setuptools\_deprecation_warning.py (0ms)
[IDX(2)]       parsing: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stubs\setuptools\setuptools\extension.pyi [fs read 25ms] (26ms)
[IDX(2)]       binding: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stubs\setuptools\setuptools\extension.pyi (0ms)
[IDX(2)]       parsing: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stubs\setuptools\setuptools\dist.pyi [fs read 43ms] (48ms)
[IDX(2)]       binding: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stubs\setuptools\setuptools\dist.pyi (1ms)
[IDX(2)]       parsing: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stubs\setuptools\setuptools\depends.pyi [fs read 20ms] (24ms)
[IDX(2)]       binding: c:\Users\pierr\.vscode-insiders\extensions\ms-python.vscode-pylance-2021.10.1-pre.1\dist\typeshed-fallback\stubs\setuptools\setuptools\depends.pyi (0ms)
[IDX(2)]     indexing: c:\Users\pierr\AppData\Local\Programs\Python\Python310\Lib\site-packages\setuptools\__init__.py [found 8] (109ms)
[IDX(2)]   index execution environment c:\Users\pierr\Documents\programmation\git\test [found 8812 in 421 files] (1152ms)
[IDX(2)] index libraries c:\Users\pierr\Documents\programmation\git\test [found 8812 in 1 exec envs] (4300ms)
[Info  - 16:50:53] [IDX(2)] Long operation: index libraries c:\Users\pierr\Documents\programmation\git\test (4300ms)
[Info  - 16:50:53] Indexer done(2). indexed 421 files

Code Snippet / Additional information

from typing import TypedDict


class MyDict(TypedDict, total=False):
    key1: int
    key2: str


my_dict: MyDict = {
    'key1': 1,
    'key2': "test"
}

print(my_dict['key1'])  # Here there is an "error"

if 'key1' in my_dict.keys():
    print(my_dict['key1'])  # Here there is an "error"

[yvvt0379]

To see logs, you should:

1. add this line "python.analysis.logLevel": "Trace" to your settings.json file.
2. go to Output, click the drop-down box, and select Pylance Language Server.

[erictraut]

The type MyDict in your example indicates that the keys are not required. In general, a type checker must assume that a not-required key is potentially not present and accessing it through an index operation will result in a runtime error.

Pyright (the type checker that underlies pylance) will "narrow" the type and (internally mark the corresponding key as no longer "not-required") based on conditional checks, like this:

if "key1" in my_dict:
    print(my_dict["key1"])

Note that you don't need to fetch the .keys() explicitly, and pyright's narrowing logic doesn't know about that pattern.

Pyright doesn't currently narrow the TypedDict type on assignment. I think that's a good enhancement request. I've created a tracking feature request in the pyright repo.

In the meantime, you can use the pattern above. Another solution is to enclose the usage in a try block. Or you can suppress the reportTypedDictNotRequiredAccess diagnostic temporarily within that file by adding the following comment somewhere:

# pyright: reportTypedDictNotRequiredAccess=false

Or you can disable that diagnostic rule throughout your entire project using pylance settings to set the diagnostic severity to "none".

[erictraut]

I've added support for TypedDict narrowing on assignment. This support will be in the next release of pylance.

[bschnurr]

This issue has been fixed in version 2021.10.1, which we've just released. You can find the changelog here: https://github.com/microsoft/pylance-release/blob/main/CHANGELOG.md#2021101-14-october-2021