From 0f695b55a95f2ce6afa96172fbc10345c8baf28e Mon Sep 17 00:00:00 2001
From: obrusvit <vit.obrusnik@gmail.com>
Date: Sun, 25 May 2025 19:18:29 +0200
Subject: [PATCH] refactor(core): fn plural_form will never panic

- also minor adjustment where the function is used in Eckahrt
---
 core/embed/rust/src/strutil.rs                | 30 +++++++++++--------
 .../firmware/value_input_screen.rs            |  8 ++---
 2 files changed, 21 insertions(+), 17 deletions(-)

diff --git a/core/embed/rust/src/strutil.rs b/core/embed/rust/src/strutil.rs
index d4854836ff..0ca2e1a265 100644
--- a/core/embed/rust/src/strutil.rs
+++ b/core/embed/rust/src/strutil.rs
@@ -82,20 +82,22 @@ pub fn format_pairing_code(code: u32, width: usize) -> ShortString {
 /// * `count` - The numeric count to select the correct plural form.
 ///
 /// # Returns
-/// A `ShortString` containing the correct plural form.
-///
-/// # Panics
-/// Panics if:
-/// - The `template` has fewer than two forms.
-/// - Conversion to `ShortString` fails (via `unwrap!`).
+/// A `ShortString` containing the correct plural form, or an empty
+/// `ShortString` if the template is malformed or conversion fails.
 pub fn plural_form(template: &str, count: u32) -> ShortString {
+    // If no separator found, return the whole template (fallback behavior)
+    if !template.contains('|') {
+        return ShortString::try_from(template).unwrap_or_default();
+    }
+
     // Split the template by '|' into components
     let mut parts = template.split('|');
 
-    // First form (singular), must exist
-    let first = unwrap!(parts.next().ok_or(()));
-    // Second form (plural or few), must exist
-    let second = unwrap!(parts.next().ok_or(()));
+    // Get the required first two parts
+    let (first, second) = match (parts.next(), parts.next()) {
+        (Some(first), Some(second)) => (first, second),
+        _ => return ShortString::default(),
+    };
     // Third form (many), optional
     let third = parts.next();
 
@@ -121,8 +123,8 @@ pub fn plural_form(template: &str, count: u32) -> ShortString {
         }
     };
 
-    // Convert the selected form into ShortString, panicking if it fails
-    unwrap!(ShortString::try_from(selected))
+    // Convert safely, returning empty string on failure
+    ShortString::try_from(selected).unwrap_or_default()
 }
 
 #[derive(Copy, Clone)]
@@ -334,8 +336,12 @@ mod tests {
     #[test]
     fn test_plural_form() {
         use super::plural_form;
+        // malformed templete, returns empty string
+        assert_eq!(plural_form("day", 1).as_str(), "day");
+        // simple singular/plural
         assert_eq!(plural_form("day|days", 1).as_str(), "day");
         assert_eq!(plural_form("day|days", 3).as_str(), "days");
+        // Czech-style singular/few/many
         assert_eq!(plural_form("den|dny|dní", 1).as_str(), "den");
         assert_eq!(plural_form("den|dny|dní", 3).as_str(), "dny");
         assert_eq!(plural_form("den|dny|dní", 5).as_str(), "dní");
diff --git a/core/embed/rust/src/ui/layout_eckhart/firmware/value_input_screen.rs b/core/embed/rust/src/ui/layout_eckhart/firmware/value_input_screen.rs
index efc552aed9..1c433e91b2 100644
--- a/core/embed/rust/src/ui/layout_eckhart/firmware/value_input_screen.rs
+++ b/core/embed/rust/src/ui/layout_eckhart/firmware/value_input_screen.rs
@@ -479,6 +479,7 @@ impl ValueInput for DurationInput {
             (self.duration.to_days(), TR::plurals__lock_after_x_days),
             (self.duration.to_hours(), TR::plurals__lock_after_x_hours),
             (self.duration.to_mins(), TR::plurals__lock_after_x_minutes),
+            (self.duration.to_secs(), TR::plurals__lock_after_x_seconds),
         ];
 
         for &(count, tr) in &units {
@@ -489,11 +490,8 @@ impl ValueInput for DurationInput {
             }
         }
 
-        // Fallback to seconds if all are 0
-        let count = self.duration.to_secs();
-        let plural = TString::from_translation(TR::plurals__lock_after_x_seconds)
-            .map(|template| plural_form(template, count));
-        (count, Some(plural))
+        // This should never be reached unless duration is exactly 0
+        (0, None)
     }
 
     fn increment(&mut self) {