Use [] and {} instead of list() and dict()

[benediktjohannes]

Description

See also #8747

Types of changes

• Non-breaking change (fix or new feature that would not break existing functionality).
• Breaking change (fix or new feature that would cause existing functionality to change).
• New tests added to cover the changes.
• Integration tests passed locally by running ./runtests.sh -f -u --net --coverage.
• Quick tests passed locally by running ./runtests.sh --quick --unittests --disttests.
• In-line docstrings updated.
• Documentation updated, tested make html command in the docs/ folder.

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📥 Commits

Reviewing files that changed from the base of the PR and between 8dafee7 and 9764d2b.

📒 Files selected for processing (1)

• monai/transforms/inverse.py

✅ Files skipped from review due to trivial changes (1)

• monai/transforms/inverse.py

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📝 Walkthrough

Walkthrough

Updated monai/transforms/inverse.py in track_transform_meta to use literal container initializers when reading nested trace-status data: statuses = pend.get(TraceKeys.STATUSES, {}) and messages = statuses.get(TraceStatusKeys.PENDING_DURING_APPLY, []). The code then appends the pending message, writes it back to statuses[TraceStatusKeys.PENDING_DURING_APPLY], stores statuses into info[TraceKeys.STATUSES], and pushes the applied operation. No API or behavior changes.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~2 minutes

🚥 Pre-merge checks | ✅ 2 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	Description references a related issue but lacks the required 'Description' section explaining the changes. Only checklist items are provided.	Add a brief description explaining why list() and dict() are being replaced with [] and {} in the Description section.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title check	✅ Passed	Title accurately summarizes the main change: replacing list() and dict() calls with literal forms [] and {}.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.

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[benediktjohannes]

@coderabbitai do you agree with these changes?

[coderabbitai]

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🧩 Analysis chain

🏁 Script executed:

#!/bin/bash
# Get the diff for the PR
git diff origin/dev...HEAD -- monai/transforms/inverse.py

Length of output: 792

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🏁 Script executed:

#!/bin/bash
# Get more context around the changed lines
cat monai/transforms/inverse.py | grep -n -B 5 -A 5 "get(TraceKeys.STATUSES"

Length of output: 551

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🏁 Script executed:

#!/bin/bash
# Check if there are any other occurrences of dict() or list() in the same file
rg -n '\b(dict|list)\(\)' monai/transforms/inverse.py

Length of output: 0

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@benediktjohannes Yes, I agree with these changes. Using [] and {} instead of list() and dict() is:

1. More Pythonic - follows PEP 8 style guidelines
2. Slightly faster - literal syntax avoids name lookups
3. More concise - improves readability

The changes are functionally equivalent and safe in this context (default arguments to .get() methods). The PR correctly identified and updated all instances in the file.

[benediktjohannes]

Wow! I am amazed how cool this tool is, I thought that this would definitely not work, just to chat here with the AI, very nice and helpful for workflows! Appreciate it! 👍

[ericspod]

Hi @benediktjohannes I commented in another PR about replacing names like this with literal syntax. I suppose this saves a name lookup but I wonder if the interpreter doesn't replace these things automatically anyway. Do you actually see any speedup here? There's probably many other places in MONAI that should have this done as well.

[benediktjohannes]

Hi @benediktjohannes I commented in another PR about replacing names like this with literal syntax. I suppose this saves a name lookup but I wonder if the interpreter doesn't replace these things automatically anyway. Do you actually see any speedup here? There's probably many other places in MONAI that should have this done as well.

I think (back then (it's already been 4 weeks now, so I'm not quite sure), I've searched for all those list() things) and it should be worth merging, see here https://towardsdatascience.com/no-and-list-are-different-in-python-8940530168b0/

[ericspod]

We can merge this too, but as I said it's something that would only matter in very high frequency code.

[benediktjohannes]

Thanks, See #8747 please