Update files and folders from camelCase to PascalCase. This script is designed to recursively update the capitalization of both files and directories in the current directory. Intended to update a project from using camelCase to PascalCase.

rename_files.sh

#!/bin/bash

# --------------------------------------------------------------------------
# Script Author: @joshcawthorne
# Warning: BACKUP ALL YOUR FILES BEFORE RUNNING THIS - THIS IS A DESTRUCTIVE 
#          OPERATION, I AM NOT RESPONSIBLE FOR ANY LOST FILES.
# OS Compatibility: MacOS, Linux, and WSL on Windows 10/11.
# --------------------------------------------------------------------------
# Description:
# -
# This script is designed to recursively update the capitalization of both
# files and directories in the current directory. Intended to update a project
# from using camelCase to PascalCase.
#
# - For files: It targets extensions ".js", ".jsx", ".ts", and ".tsx",
#   but excludes any "index.*" files.
# - For directories: It capitalizes the first letter of all directories.
# --------------------------------------------------------------------------
# Git Users:
# -
# Git is case-insensitive by default. Post-execution, explicit renaming in Git is needed.
# 1. Remove all files from Git's index: git rm -r --cached .
# 2. Re-add all files: git add .
# 3. Commit changes: git commit -m "Case-sensitive file renaming"
# --------------------------------------------------------------------------
# Instructions:
# -
# 1. Copy this file to the root of the directory you want to rename.
# 2. Run the following to make the file executable:
#    chmod +x ./rename_files.sh
# 3. Now, run the script:
#    ./rename_files.sh
# 4. Double, Triple, check that all your files and folders were updated
#    correctly BEFORE committing to any source!
# 5. SUGGESTION: If you're using something such as React, you could use
#    a codemod script to update all imports in your project: 
#    https://github.com/facebook/jscodeshift
# --------------------------------------------------------------------------


# `find ./ -type f` finds all files in the directory.
# `-iname "*.js" -o -iname "*.jsx" -o -iname "*.ts" -o -iname "*.tsx"` filters only files with the specified extensions.
# `! -iname "index.*"` excludes any index files.
find ./ -type f \( -iname "*.js" -o -iname "*.jsx" -o -iname "*.ts" -o -iname "*.tsx" \) ! -iname "index.*" | while read -r filepath; do
  # Using awk to capitalize the first letter of the filename
  # The awk logic is built to respect existing capitalization.
  newname=$(basename "$filepath" | awk 'BEGIN{FS=OFS=""} { for(i=1;i<=length($0);i++) { if(i==1 || substr($0,i-1,1)=="-") { $i=tolower($i) } } } 1')
  
  # Check if the new filename is different from the old one.
  if [ "$newname" != "$(basename "$filepath")" ]; then
    # Perform the rename operation.
    mv "$filepath" "$(dirname "$filepath")/$newname"
  fi
done

# `find ./ -type d` finds all directories.
find ./ -type d | while read -r dirpath; do
  # Similar awk logic as above, but this time for directories.
  newname=$(basename "$dirpath" | awk 'BEGIN{FS=OFS=""} { for(i=1;i<=length($0);i++) { if(i==1 || substr($0,i-1,1)=="-") { $i=tolower($i) } } } 1')

  # Check if the new directory name is different from the old one.
  if [ "$newname" != "$(basename "$dirpath")" ]; then
    # Perform the rename operation.
    mv "$dirpath" "$(dirname "$dirpath")/$newname"
  fi
done