validation: move validation crate to crates folder

crates/validation/Cargo.toml

@@ -0,0 +1,9 @@
+[package]
+authors = ["Simon Broeng Jensen <sbj@cwconsult.dk>"]
+description = "Validation logic for LLDAP"
+edition = "2021"
+homepage = "https://github.com/lldap/lldap"
+license = "GPL-3.0-only"
+name = "lldap_validation"
+repository = "https://github.com/lldap/lldap"
+version = "0.6.0"

crates/validation/src/attributes.rs

@@ -0,0 +1,45 @@
+// Description of allowed characters. Intended for error messages.
+pub const ALLOWED_CHARACTERS_DESCRIPTION: &str = "a-z, A-Z, 0-9, and dash (-)";
+
+pub fn validate_attribute_name(attribute_name: &str) -> Result<(), Vec<char>> {
+    let invalid_chars: Vec<char> = attribute_name
+        .chars()
+        .filter(|c| !(c.is_alphanumeric() || *c == '-'))
+        .collect();
+    if invalid_chars.is_empty() {
+        Ok(())
+    } else {
+        Err(invalid_chars)
+    }
+}
+
+mod tests {
+
+    #[test]
+    fn test_valid_attribute_name() {
+        let valid1: String = "AttrName-01".to_string();
+        let result = super::validate_attribute_name(&valid1);
+        assert!(result == Ok(()));
+    }
+
+    #[test]
+    fn test_invalid_attribute_name_chars() {
+        fn test_invalid_char(c: char) {
+            let prefix: String = "AttrName".to_string();
+            let suffix: String = "01".to_string();
+            let name: String = format!("{prefix}{c}{suffix}");
+            let result = super::validate_attribute_name(&name);
+            match result {
+                Ok(()) => {
+                    panic!()
+                }
+                Err(invalid) => {
+                    assert!(invalid == vec![c.to_owned()]);
+                }
+            }
+        }
+        test_invalid_char(' ');
+        test_invalid_char('_');
+        test_invalid_char('#');
+    }
+}

crates/validation/src/lib.rs

@@ -0,0 +1,3 @@
+#![forbid(non_ascii_idents)]
+
+pub mod attributes;