Restrict channel names, too.

Thankfully, channel creation only happens in one place, so we don't need a state machine for this.

1 files changed, 23 insertions, 0 deletions

diff --git a/src/channel/validate.rs b/src/channel/validate.rs
new file mode 100644
index 0000000..0c97293
--- /dev/null
+++ b/src/channel/validate.rs
@@ -0,0 +1,23 @@
+use unicode_segmentation::UnicodeSegmentation as _;
+
+use crate::name::Name;
+
+// Picked out of a hat. The power of two is not meaningful.
+const NAME_TOO_LONG: usize = 64;
+
+pub fn name(name: &Name) -> bool {
+    let display = name.display();
+
+    [
+        display.graphemes(true).count() < NAME_TOO_LONG,
+        display.chars().all(|ch| !ch.is_control()),
+        display.chars().next().is_some_and(|c| !c.is_whitespace()),
+        display.chars().last().is_some_and(|c| !c.is_whitespace()),
+        display
+            .chars()
+            .zip(display.chars().skip(1))
+            .all(|(a, b)| !(a.is_whitespace() && b.is_whitespace())),
+    ]
+    .into_iter()
+    .all(|value| value)
+}