feat: add `Grid` as a usable widget

2 files changed, 110 insertions, 0 deletions

diff --git a/src/values.rs b/src/values.rs
index d2dae74..62997ad 100644
--- a/src/values.rs
+++ b/src/values.rs
@@ -5,6 +5,7 @@ mod line_height;
 mod padding;
 mod pixels;
 mod rotation;
+mod sizing;
 
 pub trait Value: Sized {
     type Err;
diff --git a/src/values/sizing.rs b/src/values/sizing.rs
new file mode 100644
index 0000000..e6a5086
--- /dev/null
+++ b/src/values/sizing.rs
@@ -0,0 +1,109 @@
+use std::num::ParseFloatError;
+use std::str::FromStr;
+
+use iced::Length;
+use iced::widget::grid::Sizing;
+
+use super::Value;
+use super::length::ParseLengthError;
+
+#[derive(Debug, thiserror::Error, Clone, PartialEq)]
+pub enum ParseSizingError {
+    #[error("float parsing error: {0}")]
+    ParseFloatError(ParseFloatError),
+    #[error("length parsing error: {0}")]
+    ParseLengthError(#[from] ParseLengthError),
+    #[error("invalid prefix")]
+    InvalidPrefix,
+    #[error("missing prefix")]
+    MissingPrefix,
+    #[error("cannot parse sizing from empty string")]
+    Empty,
+}
+
+impl From<ParseFloatError> for ParseSizingError {
+    fn from(value: ParseFloatError) -> Self {
+        Self::ParseFloatError(value)
+    }
+}
+
+impl Value for Sizing {
+    type Err = ParseSizingError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        let s = s.trim();
+
+        if s.is_empty() {
+            return Err(ParseSizingError::Empty);
+        }
+
+        if s.starts_with(|c: char| c.is_ascii_digit()) {
+            return Err(ParseSizingError::MissingPrefix);
+        }
+
+        let (prefix, value) = s.split_at(2);
+        match prefix.to_lowercase().as_str() {
+            "ar" => Ok(Self::AspectRatio(f32::from_str(value)?)),
+            "ed" => Ok(Self::EvenlyDistribute(Length::from_str(value)?)),
+            _ => Err(ParseSizingError::InvalidPrefix),
+        }
+    }
+
+    fn to_string(&self) -> String {
+        match self {
+            Self::AspectRatio(ratio) => format!("ar{ratio}"),
+            Self::EvenlyDistribute(length) => {
+                format!("ed{}", length.to_string())
+            }
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn can_parse_ratio() {
+        assert_eq!(Sizing::from_str("ar5.1"), Ok(Sizing::AspectRatio(5.1)))
+    }
+
+    #[test]
+    fn can_parse_distribute_with_space() {
+        assert_eq!(
+            Sizing::from_str("  edfp2 "),
+            Ok(Sizing::EvenlyDistribute(Length::FillPortion(2)))
+        )
+    }
+
+    #[test]
+    fn cant_parse_invalid_prefix() {
+        assert_eq!(
+            Sizing::from_str("bc4.1 "),
+            Err(ParseSizingError::InvalidPrefix)
+        )
+    }
+
+    #[test]
+    fn cant_parse_invalid_float() {
+        assert_eq!(
+            Sizing::from_str(" ar2.a"),
+            Err(ParseSizingError::ParseFloatError(
+                f32::from_str("2.a").expect_err("float parse should fail")
+            ))
+        )
+    }
+
+    #[test]
+    fn cant_parse_with_missing_prefix() {
+        assert_eq!(
+            Sizing::from_str("2.4"),
+            Err(ParseSizingError::MissingPrefix)
+        )
+    }
+
+    #[test]
+    fn cant_parse_empty_string() {
+        assert_eq!(Sizing::from_str(" "), Err(ParseSizingError::Empty))
+    }
+}