Upstream twpayne/chezmoi state of the touched files before 41a618c046

internal/cmd/shellquote.go

@@ -0,0 +1,67 @@
+package cmd
+
+import (
+	"regexp"
+	"strings"
+)
+
+// nonShellLiteralRx is a regular expression that matches anything that is not a
+// shell literal.
+var nonShellLiteralRx = regexp.MustCompile(`[^+\-./0-9=A-Z_a-z]`)
+
+// shellQuote returns s quoted as a shell argument, if necessary.
+func shellQuote(s string) string {
+	const (
+		backslash   = '\\'
+		singleQuote = '\''
+	)
+
+	switch {
+	case s == "":
+		return "''"
+	case nonShellLiteralRx.MatchString(s):
+		result := make([]byte, 0, 2+len(s))
+		inSingleQuotes := false
+		for _, b := range []byte(s) {
+			switch b {
+			case backslash:
+				if !inSingleQuotes {
+					result = append(result, singleQuote)
+					inSingleQuotes = true
+				}
+				result = append(result, backslash, backslash)
+			case singleQuote:
+				if inSingleQuotes {
+					result = append(result, singleQuote)
+					inSingleQuotes = false
+				}
+				result = append(result, '\\', singleQuote)
+			default:
+				if !inSingleQuotes {
+					result = append(result, singleQuote)
+					inSingleQuotes = true
+				}
+				result = append(result, b)
+			}
+		}
+		if inSingleQuotes {
+			result = append(result, singleQuote)
+		}
+		return string(result)
+	default:
+		return s
+	}
+}
+
+// shellQuoteCommand returns a string containing command and args shell quoted.
+func shellQuoteCommand(command string, args []string) string {
+	if len(args) == 0 {
+		return shellQuote(command)
+	}
+	elems := make([]string, 1+len(args))
+	elems[0] = shellQuote(command)
+	for i, arg := range args {
+		elems[i+1] = shellQuote(arg)
+	}
+	return strings.Join(elems, " ")
+}