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.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

---

📝 Walkthrough

Walkthrough

Modified monai/transforms/inverse.py to replace two defaultdict-like initializations with literal equivalents. In the track_transform_meta function, changed dict() to {} and list() to [] when accessing nested transform-trace status structures. The behavior remains unchanged; only syntax preference was updated.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~2 minutes

🚥 Pre-merge checks | ✅ 2 | ❌ 1

❌ Failed checks (1 inconclusive)

Check name	Status	Explanation	Resolution
Description check	❓ Inconclusive	Description references issue #8747 and indicates it's a non-breaking change, but lacks a detailed explanation of what was changed and why.	Add a brief description of the specific changes made (which file, which lines, what was replaced) and the rationale for the change.

✅ Passed checks (2 passed)

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

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

• 📝 Generate docstrings (stacked PR)
• 📝 Generate docstrings (commit on current branch)

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[benediktjohannes]

@coderabbitai do you agree with these changes?

[coderabbitai]

Tip

For best results, initiate chat on the files or code changes.

🧩 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

---

🏁 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

---

🏁 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

---

@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! 👍