continue working on config and default parsing

internal/util/file.go

@@ -0,0 +1,58 @@
+package util
+
+import (
+	"io"
+	"os"
+)
+
+// WriteFile writes a given byte array to the given path.
+func WriteFile(b []byte, p string) error {
+	f, err := os.Create(p)
+	if err != nil {
+		return err
+	}
+	_, err = f.Write(b)
+	defer f.Close()
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// ReadFile reads a byte array from a given path.
+func ReadFile(p string) ([]byte, error) {
+	f, err := os.Open(p)
+	if err != nil {
+		return nil, err
+	}
+	var result []byte
+	buf := make([]byte, 1024)
+	for {
+		n, err := f.Read(buf)
+		// check for a non EOF error
+		if err != nil && err != io.EOF {
+			return nil, err
+		}
+		// n==0 when there are no chunks left to read
+		if n == 0 {
+			defer f.Close()
+			break
+		}
+		result = append(result, buf[:n]...)
+	}
+	return result, nil
+}
+
+// CopyFile reads the file at the input path, and write
+// it to the output path.
+func CopyFile(inPath string, outPath string) error {
+	inB, err := ReadFile(inPath)
+	if err != nil {
+		return err
+	}
+	if err := WriteFile(inB, outPath); err != nil {
+		return err
+	} else {
+		return nil
+	}
+}

internal/util/path.go

@@ -40,6 +40,13 @@ func ReplaceRoot(inPath, outRoot string) string {
 	return outPath
 }
 
+// FileExists returns a boolean indicating
+// whether something exists at the path.
+func FileExists(path string) bool {
+	_, err := os.Stat(path)
+	return !os.IsNotExist(err)
+}
+
 func CreateParents(path string) error {
 	dir := filepath.Dir(path)
 	// Check if the parent directory already exists

internal/util/util.go

@@ -1,6 +1,9 @@
 package util
 
-import "strings"
+import (
+	"errors"
+	"strings"
+)
 
 func NormalizeContent(content string) string {
 	var normalized []string
@@ -13,3 +16,8 @@ func NormalizeContent(content string) string {
 	}
 	return strings.Join(normalized, "\n")
 }
+
+// ErrorPrepend returns a new error with a message prepended to the given error.
+func ErrorPrepend(m string, err error) error {
+	return errors.Join(errors.New(m), err)
+}