Code Rename

Code Rename Skill

Safely rename symbols across a codebase. This skill covers the full workflow from finding occurrences to applying changes.

Workflow Overview

1. Find all occurrences (definition + usages)
2. Review matches (verify no false positives)
3. Apply changes (Edit tool or bulk rename)
4. Verify (run tests, lint)

Clojure Rename

Use clj-kondo to find all occurrences, then Edit tool to apply changes.

Step 1: Find All Occurrences

# Find definition and all usages
clj-kondo --lint . \
  --config '{:output {:format :json}, :analysis {:var-definitions true, :var-usages true}}' \
  | jq '[.analysis.var_definitions[], .analysis.var_usages[]]
        | .[] | select(.name == "old-name")
        | {file: .filename, row, col, end_col, type: (if .defined_by then "def" else "usage" end)}'

Step 2: Review Matches

Check the output for:

• Is the definition found?
• Are all usages in expected files?
• Any matches in strings/comments to skip?

Step 3: Apply Changes

Option A: Edit tool (precise) Use the Edit tool for each location, starting from the last occurrence (to preserve line numbers).

Option B: ripgrep + Edit (simple cases)

# Find files
rg -l '\bold-name\b' --type clojure

# Preview matches with context
rg '\bold-name\b' --type clojure -C 2

# Then use Edit tool on each file

Step 4: Handle Namespace-Qualified References

Don't forget qualified references:

rg 'my\.namespace/old-name' --type clojure

Clojure Rename Checklist

• Definition renamed
• All usages in same namespace renamed
• Namespace-qualified usages renamed (ns/old-name)
• Aliased usages renamed (alias/old-name)
• Docstrings/comments updated (if needed)
• Tests pass

JavaScript/TypeScript Rename

Use ast-grep for structural renaming.

Simple Rename (All Occurrences)

# Preview changes
ast-grep run --pattern 'oldName' --rewrite 'newName' --lang js src/

# Apply changes
ast-grep run --pattern 'oldName' --rewrite 'newName' --lang js src/ --update-all

# Interactive review
ast-grep run --pattern 'oldName' --rewrite 'newName' --lang js src/ --interactive

Rename Function Definition + Calls

# Rename function definition
ast-grep run \
  --pattern 'function oldName($$$ARGS) { $$$BODY }' \
  --rewrite 'function newName($$$ARGS) { $$$BODY }' \
  --lang js src/ --update-all

# Rename function calls
ast-grep run \
  --pattern 'oldName($$$)' \
  --rewrite 'newName($$$)' \
  --lang js src/ --update-all

Rename Class

# Rename class definition
ast-grep run \
  --pattern 'class OldClass { $$$BODY }' \
  --rewrite 'class NewClass { $$$BODY }' \
  --lang js src/ --update-all

# Rename instantiations
ast-grep run \
  --pattern 'new OldClass($$$)' \
  --rewrite 'new NewClass($$$)' \
  --lang js src/ --update-all

Rename with YAML Rule

# rename.yaml
id: rename-symbol
language: JavaScript
rule:
  pattern: oldSymbol
fix: newSymbol

ast-grep scan --rule rename.yaml src/ --update-all

Python Rename

# Rename function
ast-grep run --pattern 'old_function' --rewrite 'new_function' --lang py src/ --update-all

# Rename class
ast-grep run --pattern 'OldClass' --rewrite 'NewClass' --lang py src/ --update-all

# Rename with structure preservation
ast-grep run \
  --pattern 'def old_func($$$ARGS):' \
  --rewrite 'def new_func($$$ARGS):' \
  --lang py src/ --update-all

Go Rename

# Rename function
ast-grep run \
  --pattern 'func OldName($$$)' \
  --rewrite 'func NewName($$$)' \
  --lang go . --update-all

# Rename type
ast-grep run \
  --pattern 'type OldType struct { $$$FIELDS }' \
  --rewrite 'type NewType struct { $$$FIELDS }' \
  --lang go . --update-all

Rust Rename

# Rename function
ast-grep run \
  --pattern 'fn old_name($$$)' \
  --rewrite 'fn new_name($$$)' \
  --lang rust src/ --update-all

# Rename struct
ast-grep run \
  --pattern 'struct OldName { $$$FIELDS }' \
  --rewrite 'struct NewName { $$$FIELDS }' \
  --lang rust src/ --update-all

Fallback: ripgrep + Edit

When ast-grep doesn't work (unsupported language, complex case):

# Step 1: Find all occurrences
rg -n '\bold_name\b' src/

# Step 2: List files
rg -l '\bold_name\b' src/

# Step 3: Preview with context
rg '\bold_name\b' -C 3 src/

# Step 4: Use Edit tool on each file
# Start from last file to preserve line numbers

Safety Checklist

Before Renaming

• Commit or stash current changes
• Understand the scope (local vs exported)
• Check for string literals containing the name
• Check for dynamic references (reflection, eval)

During Renaming

• Use --interactive or preview first
• Check for partial matches (e.g., user vs username)
• Use word boundaries (\b) in regex searches

After Renaming

• Run linter (clj-kondo, eslint, etc.)
• Run tests
• Search for remaining occurrences
• Review diff before committing

Common Pitfalls

1. Partial Matches

Problem: Renaming user also changes username

Solution: Use word boundaries

rg '\buser\b'  # Won't match "username"
ast-grep run --pattern 'user' --rewrite 'account'  # ast-grep is syntax-aware

2. String Literals

Problem: Renaming changes strings that shouldn't change

Solution: Review matches, use --interactive

ast-grep run --pattern 'oldName' --rewrite 'newName' --lang js --interactive

3. Different Contexts

Problem: Same name in different contexts

Solution: Use structural patterns

# Only rename in function calls, not variable declarations
ast-grep run --pattern 'oldFunc($$$)' --rewrite 'newFunc($$$)' --lang js

4. Namespace-Qualified Names

Problem: Missing qualified references

Solution: Search for all variations

# Clojure
rg 'old-name|ns/old-name|alias/old-name' --type clojure

# JavaScript
rg 'oldName|module\.oldName|obj\.oldName' --type js

When to Use Each Approach