feat(tricks): strings is empty

Signed-off-by: Pouyan Heyratpour <[email protected]>

tricks/string.go

@@ -1,5 +1,11 @@
 package tricks
 
+import "strings"
+
 func StringToRunes(src string) []rune {
 	return []rune(src)
 }
+
+func IsEmptyString(s string) bool {
+	return len(strings.TrimSpace(s)) == 0
+}

tricks/string_test.go

@@ -14,3 +14,25 @@ func TestStringToRunes(t *testing.T) {
 	assert.Equal(t, []rune{'a', 'b', ' ', 'c', 'd'}, tricks.StringToRunes("ab cd"))
 	assert.Equal(t, []rune{'a', 'b', 'b', 'a'}, tricks.StringToRunes("abba"))
 }
+
+func TestIsEmptyString(t *testing.T) {
+	tcc := []struct {
+		s      string
+		result bool
+	}{
+		{"", true},
+		{" ", true},
+		{"   ", true},
+		{".", false},
+		{" .", false},
+		{" . ", false},
+		{" _ ", false},
+		{" - ", false},
+		{"hello", false},
+	}
+
+	for k, tc := range tcc {
+		result := tricks.IsEmptyString(tc.s)
+		assert.Equalf(t, tc.result, result, "test case #%d '%s': expected %v, got %v", k, tc.s, tc.result, result)
+	}
+}