Handle Maxspeed Bugs Gracefully (#190)

* Handle Maxspeed Bugs Gracefully

* Passthrough error display

data/tests.yml

@@ -309,9 +309,8 @@
 - way_id: 102917976
   description: Road with impossible speed limit
   rust:
-    false
-    #expect_warnings: true
-    #separator: true
+    expect_warnings: true
+    separator: false
   tags:
     bicycle: "designated"
     cycleway: "lane"

osm2lanes/src/metric.rs

@@ -75,8 +75,22 @@ pub enum SpeedError {
     Empty,
     Parse(std::num::ParseFloatError),
     UnknownUnit(String),
+    OutOfRange,
 }
 
+impl std::fmt::Display for SpeedError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            Self::Empty => write!(f, "empty"),
+            Self::Parse(e) => e.fmt(f),
+            Self::UnknownUnit(unit) => write!(f, "unknown unit '{unit}'"),
+            Self::OutOfRange => write!(f, "out of range"),
+        }
+    }
+}
+
+impl std::error::Error for SpeedError {}
+
 impl std::convert::From<std::num::ParseFloatError> for SpeedError {
     fn from(e: std::num::ParseFloatError) -> Self {
         SpeedError::Parse(e)
@@ -89,12 +103,16 @@ impl std::str::FromStr for Speed {
         if s.is_empty() {
             return Err(SpeedError::Empty);
         }
-        match s.split_once(' ') {
-            None => Ok(Self::Kph(s.parse()?)),
-            Some((s, "mph")) => Ok(Self::Mph(s.parse()?)),
-            Some((s, "knots")) => Ok(Self::Knots(s.parse()?)),
-            Some((_, unit)) => Err(SpeedError::UnknownUnit(unit.to_owned())),
+        let speed = match s.split_once(' ') {
+            None => Self::Kph(s.parse()?),
+            Some((s, "mph")) => Self::Mph(s.parse()?),
+            Some((s, "knots")) => Self::Knots(s.parse()?),
+            Some((_, unit)) => return Err(SpeedError::UnknownUnit(unit.to_owned())),
+        };
+        if speed.kph() < 0_f64 || speed.kph() > 300_f64 {
+            return Err(SpeedError::OutOfRange);
         }
+        Ok(speed)
     }
 }
 

osm2lanes/src/transform/tags_to_lanes/road.rs

@@ -178,8 +178,11 @@ impl RoadBuilder {
         const MAXSPEED: TagKey = TagKey::from("maxspeed");
         let max_speed = match tags.get(MAXSPEED).map(str::parse::<Speed>).transpose() {
             Ok(max_speed) => max_speed,
-            Err(_e) => {
-                warnings.push(TagsToLanesMsg::unsupported_tags(tags.subset(&[MAXSPEED])));
+            Err(e) => {
+                warnings.push(TagsToLanesMsg::unsupported(
+                    &e.to_string(),
+                    tags.subset(&[MAXSPEED]),
+                ));
                 None
             },
         };