nathanbabcock · February 13, 2023 19:20 · Feb 13, 2023
diff --git a/comma_iter.rs b/comma_iter.rs
@@ -0,0 +1,59 @@
+use std::str::Chars;
+
+/// An iterator over comma-separated values, **ignoring commas inside parentheses**.
+///
+/// ## Examples
+///
+/// ```rust
+/// use ffmpeg_sidecar::util::CommaIter;
+///
+/// let string = "foo(bar,baz),quux";
+/// let mut iter = CommaIter::new(string);
+///
+/// assert_eq!(iter.next(), Some("foo(bar,baz)"));
+/// assert_eq!(iter.next(), Some("quux"));
+/// assert_eq!(iter.next(), None);
+/// ```
+pub struct CommaIter<'a> {
+  chars: Chars<'a>,
+}
+
+impl<'a> CommaIter<'a> {
+  pub fn new(string: &'a str) -> Self {
+    Self {
+      chars: string.chars(),
+    }
+  }
+}
+
+impl<'a> Iterator for CommaIter<'a> {
+  type Item = &'a str;
+
+  /// Return the next comma-separated section, not including the comma.
+  fn next(&mut self) -> Option<Self::Item> {
+    let chars_clone = self.chars.clone();
+    let mut i = 0;
+
+    while let Some(char) = self.chars.next() {
+      match char {
+        '(' => {
+          // advance until closing paren (only handles one level nesting)
+          while let Some(close_paren) = self.chars.next() {
+            i += 1;
+            if close_paren == ')' {
+              break;
+            }
+          }
+        }
+        ',' => break,
+        _ => {}
+      }
+      i += 1;
+    }
+
+    match i {
+      0 => None,
+      _ => Some(&chars_clone.as_str()[..i]),
+    }
+  }
+}