Merge pull request #1 from iutx/feat/add-Predefined-GenerateOptions

feat: add predefined GenerateOptions

Author: iutx

README.md

@@ -1,5 +1,9 @@
 # RandomX - Random String Generator
 
+[![license](https://img.shields.io/github/license/tailabs/randomx.svg)](https://github.com/tailabs/randomx/blob/main/LICENSE)
+[![Go Report Card](https://goreportcard.com/badge/github.com/tailabs/randomx)](https://goreportcard.com/report/github.com/tailabs/randomx)
+[![release](https://img.shields.io/github/release/tailabs/randomx/all.svg)](https://github.com/tailabs/randomx/releases)
+
 RandomX is a Go package that provides a user-friendly tool for generating random strings. It enables you to generate random strings of specified lengths with various character sets, including lowercase letters, uppercase letters, digits, and symbols.
 
 This package was developed with the assistance of [ChatGPT 3.5](https://openai.com/), an advanced language model created by OpenAI.
@@ -12,7 +16,6 @@ To incorporate RandomX into your Go project, you can easily install it with the
 go get -u github.com/tailabs/randomx
 ```
 
-
 ## Usage
 
 Here's an example demonstrating how to use the RandomX package to generate random strings:

randomx.go

@@ -13,6 +13,30 @@ const (
 	Symbols          = "!@#$%^&*()-_=+[]{}|;:,.<>?/~"
 )
 
+// Predefined GenerateOptions for commonly used character sets
+var (
+	OptionAllChars = GenerateOptions{
+		UseLowercase: true,
+		UseUppercase: true,
+		UseDigits:    true,
+		UseSymbols:   true,
+	}
+
+	OptionLetters = GenerateOptions{
+		UseLowercase: true,
+		UseUppercase: true,
+		UseDigits:    false,
+		UseSymbols:   false,
+	}
+
+	OptionDigitsOnly = GenerateOptions{
+		UseLowercase: false,
+		UseUppercase: false,
+		UseDigits:    true,
+		UseSymbols:   false,
+	}
+)
+
 // Interface defines the methods for generating random strings.
 type Interface interface {
 	GenerateRandomString(length int, charSet string) string

randomx_test.go

@@ -60,3 +60,44 @@ func TestProvider_GenerateRandomStringFromBuiltin(t *testing.T) {
 		}
 	}
 }
+
+func TestProvider_GenerateRandomStringFromBuiltin_PredefinedOptions(t *testing.T) {
+	rx := New().(*provider)
+
+	tests := []struct {
+		length  int
+		options GenerateOptions
+	}{
+		{15, OptionAllChars},
+		{10, OptionLetters},
+		{8, OptionDigitsOnly},
+	}
+
+	for _, test := range tests {
+		randomStr := rx.GenerateRandomStringFromBuiltin(test.length, test.options)
+
+		expectedCharSet := ""
+		if test.options.UseLowercase {
+			expectedCharSet += LowercaseLetters
+		}
+		if test.options.UseUppercase {
+			expectedCharSet += UppercaseLetters
+		}
+		if test.options.UseDigits {
+			expectedCharSet += Digits
+		}
+		if test.options.UseSymbols {
+			expectedCharSet += Symbols
+		}
+
+		if len(randomStr) != test.length {
+			t.Errorf("Generated string length does not match expected length for options %+v", test.options)
+		}
+
+		for _, char := range randomStr {
+			if !strings.Contains(expectedCharSet, string(char)) {
+				t.Errorf("Generated string contains unexpected character: %s", string(char))
+			}
+		}
+	}
+}