replace-enzyme-with-testing-library.js

export default function transformer(file, api) {
  const AST = api.jscodeshift(file.source);

  const {
    identifier,
    callExpression,
    memberExpression,
    CallExpression,
    ImportDeclaration,
    importDeclaration,
    importSpecifier,
    literal
  } = api.jscodeshift;

  const imports = AST.find(ImportDeclaration, {
    source: { value: "enzyme" }
  });

  if (imports.length < 1) return AST.toSource();

  imports.replaceWith(
    importDeclaration(
      [importSpecifier(identifier("render"))],
      literal("@testing-library/react")
    )
  );

  function getProgram(p) {
    if (p.name === "program") {
      return true;
    }

    return getProgram(p.parent);
  }

  function replaceFunctionCall(name) {
    AST.find(CallExpression, { callee: { name } })
      .filter(p => getProgram(p) === getProgram(imports.get()))
      .replaceWith(p =>
        memberExpression(
          callExpression(identifier("render"), p.node.arguments),
          callExpression(identifier("asFragment"), []),
          false
        )
      );
  }

  for (const id of ["shallow", "mount", "render"]) {
    replaceFunctionCall(id);
  }

  return AST.toSource();
}