Fix temperature values not being accessible due to NaN values (#650)

* Fix NaN values making JSON not accessible

* Explain NaN replacement

* Report fix in changelog

CHANGELOG.md

@@ -26,6 +26,7 @@ All notable changes to eww will be listed here, starting at changes since versio
 - Fix deflisten scripts not always getting cleaned up properly
 - Add `:round-digits` to scale widget (By: gavynriebau)
 - Fix cirular-progress not properly displaying 100% values when clockwise is false
+- Fix temperatures inside `EWW_TEMPS` not being accessible if at least one value is `NaN`
 
 
 ## 0.3.0 (26.05.2022)

crates/eww/src/config/system_stats.rs

@@ -60,7 +60,13 @@ pub fn get_temperatures() -> String {
         "{{ {} }}",
         c.components()
             .iter()
-            .map(|c| format!(r#""{}": {}"#, c.label().to_uppercase().replace(' ', "_"), c.temperature()))
+            .map(|c| format!(
+                r#""{}": {}"#,
+                c.label().to_uppercase().replace(' ', "_"),
+                // It is common for temperatures to report a non-numeric value.
+                // Tolerate it by serializing it as the string "null"
+                c.temperature().to_string().replace("NaN", "\"null\"")
+            ))
             .join(",")
     )
 }