The run command executes a codemod against your local codebase, showing you the changes and applying them to your filesystem. 
codegen run rename-function

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Usage

codegen run LABEL [OPTIONS]

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Arguments

  • LABEL: The name of the codemod to run (e.g., “rename-function”)

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Options

  • --diff-preview N: Show a preview of the first N lines of the diff
  • --arguments JSON: Pass arguments to the codemod as a JSON string (required if the codemod expects arguments)

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Examples

Run a codemod: 
codegen run rename-function
Run with a diff preview limited to 50 lines: 
codegen run rename-function --diff-preview 50
Run with arguments (for codemods that require them): 
codegen run rename-function --arguments '{"old_name": "getUserData", "new_name": "fetchUserProfile"}'

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Output

The command will:
  1. Parse your codebase
  2. Run the codemod
  3. Show a diff preview (if requested)
  4. Apply changes to your filesystem

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Execution Flow

When you run a codemod:
  1. Codegen parses your entire codebase into a graph representation
  2. The codemod function is executed against this graph
  3. Any changes made by the codemod are tracked
  4. Changes are automatically applied to your local files
  5. A summary of changes is displayed
The codebase parsing step may take a few moments for larger codebases. Learn more in How it Works