chore(basic): Fixed a few clippy issues

Author: ngeor

rusty_basic/src/interpreter/built_ins/string_fn.rs

@@ -40,7 +40,7 @@ fn run_with_ascii_code_argument(count: usize, ascii: i32) -> Result<String, Runt
 }
 
 fn run_with_char(count: usize, ch: char) -> Result<String, RuntimeError> {
-    Ok(std::iter::repeat(ch).take(count).collect())
+    Ok(std::iter::repeat_n(ch, count).collect())
 }
 
 #[cfg(test)]

rusty_basic/src/interpreter/built_ins/val.rs

@@ -27,7 +27,7 @@ fn val(s: &str) -> Result<Variant, VariantError> {
     let mut state: u8 = STATE_INITIAL;
 
     for c in s.chars() {
-        if ('0'..='9').contains(&c) {
+        if c.is_ascii_digit() {
             if state == STATE_INITIAL || state == STATE_SIGN {
                 state = STATE_INT;
             } else if state == STATE_DOT {

rusty_basic/src/interpreter/default_stdlib.rs

@@ -8,10 +8,7 @@ impl Stdlib for DefaultStdlib {
     }
 
     fn get_env_var(&self, name: &str) -> String {
-        match std::env::var(name) {
-            Ok(x) => x,
-            Err(_) => String::new(),
-        }
+        std::env::var(name).unwrap_or_default()
     }
 
     fn set_env_var(&mut self, name: String, value: String) {

rusty_basic/src/interpreter/handlers/allocation.rs

@@ -4,7 +4,7 @@ use rusty_variant::{UserDefinedTypeValue, VArray, Variant};
 
 use crate::RuntimeError;
 
-/// TODO add unit tests
+// TODO add unit tests
 
 /// Creates the default variant for the given type.
 pub fn allocate_built_in(type_qualifier: TypeQualifier) -> Variant {

rusty_basic/src/interpreter/io.rs

@@ -92,7 +92,7 @@ impl FileInfo {
         let offset = ((record_number - 1) * self.rec_len) as u64;
         let file = self.random.as_mut().expect("Should have file");
         file.seek(SeekFrom::Start(offset))?;
-        let mut buffer: Vec<u8> = std::iter::repeat(0_u8).take(self.rec_len).collect();
+        let mut buffer: Vec<u8> = std::iter::repeat_n(0_u8, self.rec_len).collect();
         let bytes_read = file.read(&mut buffer)?;
         if bytes_read < buffer.len() {
             // zero out missing bytes

rusty_basic/src/interpreter/read_input.rs

@@ -81,12 +81,11 @@ impl<T: Read> ReadInputSource<T> {
             if let Some(ch) = self.read()? {
                 if predicate(ch as char) {
                     // if it was '\r', try to also get the next '\n', if exists
-                    if ch as char == '\r' {
-                        if let Some(next_ch) = self.peek()?
-                            && next_ch as char == '\n'
-                        {
-                            self.read()?;
-                        }
+                    if ch as char == '\r'
+                        && let Some(next_ch) = self.peek()?
+                        && next_ch as char == '\n'
+                    {
+                        self.read()?;
                     }
                 } else {
                     buf.push(ch);