📝 Update WaitForError comment and add README.md for project documentation.

README.md

@@ -0,0 +1,104 @@
+# waiterr
+
+`waiterr` is a Go package that wraps `sync.WaitGroup` with enhanced error handling capabilities. It allows you to run multiple goroutines, collect any errors they return, and wait for their completion, either returning the first error encountered or aggregating all errors.
+
+## Features
+
+-   **`Go(f func() error)`**: Runs a function `f` in a new goroutine, storing any error it returns.
+-   **`Wait() error`**: Waits for all goroutines to complete and returns a combined error of all non-nil errors.
+-   **`WaitForError() error`**: Waits for the first error to be returned by any goroutine and immediately returns that error. If all goroutines complete without error, it returns `nil`.
+-   **`Unwrap() []error`**: Returns a slice of all non-nil errors encountered by the goroutines.
+
+## Installation
+
+To install `waiterr`, use `go get`:
+
+```bash
+go get codeberg.org/danjones000/waiterr
+```
+
+## Usage
+
+Here's a basic example of how to use `waiterr`:
+
+```go
+package main
+
+import (
+	"errors"
+	"fmt"
+	"time"
+
+	"codeberg.org/danjones000/waiterr"
+)
+
+func main() {
+	we := new(waiterr.WaitErr)
+
+	we.Go(func() error {
+		time.Sleep(100 * time.Millisecond)
+		fmt.Println("Goroutine 1 finished")
+		return nil
+	})
+
+	we.Go(func() error {
+		time.Sleep(50 * time.Millisecond)
+		fmt.Println("Goroutine 2 finished with an error")
+		return errors.New("something went wrong in goroutine 2")
+	})
+
+	we.Go(func() error {
+		time.Sleep(150 * time.Millisecond)
+		fmt.Println("Goroutine 3 finished")
+		return nil
+	})
+
+	// Wait for all goroutines and get all errors
+	if err := we.Wait(); err != nil {
+		fmt.Printf("All goroutines finished. Combined error: %v
+", err)
+	}
+
+	// You can also get the first error immediately
+	we2 := new(waiterr.WaitErr)
+	we2.Go(func() error {
+		time.Sleep(100 * time.Millisecond)
+		return errors.New("first error from we2")
+	})
+	we2.Go(func() error {
+		time.Sleep(50 * time.Millisecond)
+		return errors.New("second error from we2")
+	})
+
+	if err := we2.WaitForError(); err != nil {
+		fmt.Printf("First error from we2: %v
+", err)
+	}
+
+	// Get all unwrapped errors
+	unwrappedErrors := we.Unwrap()
+	if len(unwrappedErrors) > 0 {
+		fmt.Println("Unwrapped errors:")
+		for i, err := range unwrappedErrors {
+			fmt.Printf("  %d: %v
+", i+1, err)
+		}
+	}
+}
+```
+
+## Contributing
+
+Please refer to the [AGENTS.md](AGENTS.md) file for guidelines on contributing to this project, including code style, commit messages, and Git workflow.
+
+## License
+
+This project is licensed under the MIT License. See the [LICENSE](LICENSE) file for details.
+
+## Go Version
+
+Go 1.25.3
+
+## Dependencies
+
+-  `github.com/nalgeon/be v0.3.0` for testing.

waiterr.go

@@ -47,7 +47,7 @@ func (we *WaitErr) Go(f func() error) {
 }
 
 // WaitForError waits for the first error to be returned by one of our go routines, and immediately returns
-// with that error. If all functions return successfully, a nil is returned.
+// with that error. If all functions return successfully, a nil is returned. It will panic if called before Go.
 func (we *WaitErr) WaitForError() error {
 	if we.errCh == nil {
 		panic("WaitForError called before Go, errCh is nil")