# Background

The package `ctx` was adding to Golang after people had started using requests.
In order to use [ctxerr](https://github.com/mvndaai/ctxerr) you need context passed with every function that returns and error.
This is a find and replace that adds `ctx context.Context` to all functions that return an error.

# What to do

1. Open VSCode or Curser and do an editor serach `cmd + shift + f`
2. Set it to regex find by clicking the `.*` button
3. Paste find below as the search 
4. In `files to include` add `*.go`
5. In `files to exclude` add `mock_*.go, *_test.go`
6. Click the `>` to allow replace
7. In the replace field paste below
   * The `$1` and `$4` are the matched groups in `()`
8. Make sure you didn't change interface functions like `MarshalJSON` or handler funcs


* Empty parameter 
   * Find - `(func (\(.*\) )*[A-za-z]+)(\()(?!ctx)(\).*error.*\{)`
   * Replace - `$1(ctx context.Context$4`
 * Has parameters (needs a comma)
   * Find - `(func (\(.*\) )*[A-za-z]+)(\()(?!ctx)(.*[a-z]+\).*error.*\{)`
   * Replace - `$1(ctx context.Context, $4`

# Testing

In [regex101](https://regex101.com/) I was matching against this list
```
func Foo() {
func Foo() error {
func (h *hello) Foo() {
func (h *hello) Foo() error {
func (h *hello) Foo(s string) error {
func (h *hello) Foo() (int, error) {
func Foo() string {
func Foo() (string, int) {
func Foo(s string) (string, error) {

func Foo(ctx context.Context) {
func Foo(ctx context.Context) error {
func (h *hello) Foo(ctx context.Context) {
func (h *hello) Foo(ctx context.Context) error {
func (h *hello) Foo(ctx context.Context, s string) error {
func (h *hello) Foo(ctx context.Context) (int, error) {
func Foo(ctx context.Context) string {
func Foo(ctx context.Context) (string, int) {
func Foo(ctx context.Context, s string) (string, error) {
```