Added unit tests for stringutils GenerateRandomAlphaOnlyString and GenerateRandomAsciiString

Signed-off-by: Peter Esbensen <pkesbensen@gmail.com>

stringutils/stringutils_test.go

@@ -23,3 +23,58 @@ func TestRandomStringUniqueness(t *testing.T) {
 		set[str] = struct{}{}
 	}
 }
+
+func testLengthHelper(generator func(int) string, t *testing.T) {
+	expectedLength := 20
+	s := generator(expectedLength)
+	if len(s) != expectedLength {
+		t.Fatalf("Length of %s was %d but expected length %d", s, len(s), expectedLength)
+	}	
+}
+
+func testUniquenessHelper(generator func(int) string, t *testing.T) {
+	repeats := 25
+	set := make(map[string]struct{}, repeats)
+	for i := 0; i < repeats; i = i + 1 {
+		str := generator(64)
+		if len(str) != 64 {
+			t.Fatalf("Id returned is incorrect: %s", str)
+		}
+		if _, ok := set[str]; ok {
+			t.Fatalf("Random number is repeated")
+		}
+		set[str] = struct{}{}
+	}
+}
+
+func isASCII(s string) bool {
+	for _, c := range s {
+		if c > 127 {
+			return false
+		}
+	}
+	return true
+}
+
+func TestGenerateRandomAlphaOnlyStringLength(t *testing.T) {
+	testLengthHelper(GenerateRandomAlphaOnlyString, t)
+}
+
+func TestGenerateRandomAlphaOnlyStringUniqueness(t *testing.T) {
+	testUniquenessHelper(GenerateRandomAlphaOnlyString, t)
+}
+
+func TestGenerateRandomAsciiStringLength(t *testing.T) {
+	testLengthHelper(GenerateRandomAsciiString, t) 
+}
+
+func TestGenerateRandomAsciiStringUniqueness(t *testing.T) {
+	testUniquenessHelper(GenerateRandomAsciiString, t)
+}
+
+func TestGenerateRandomAsciiStringIsAscii(t *testing.T) {
+	str := GenerateRandomAsciiString(64)
+	if !isASCII(str) {
+		t.Fatalf("%s contained non-ascii characters", str)
+	}
+}