fix(format): Correctly deserialize json5 (#690)

Fixes #689

Author: epage

src/file/format/json5.rs

@@ -25,7 +25,7 @@ impl<'de> serde::de::Deserialize<'de> for Val {
             .i64(|value| Ok(Self::Integer(value)))
             .f64(|value| Ok(Self::Float(value)))
             .string(|value| Ok(Val::String(value.to_owned())))
-            .none(|| Ok(Self::Null))
+            .unit(|| Ok(Self::Null))
             .seq(|value| value.deserialize().map(Val::Array))
             .map(|value| value.deserialize().map(Val::Object))
             .deserialize(d)

tests/testsuite/file_json.rs

@@ -16,6 +16,7 @@ fn test_file() {
         place: Place,
         #[serde(rename = "arr")]
         elements: Vec<String>,
+        nullable: Option<String>,
     }
 
     #[derive(Debug, Deserialize)]
@@ -52,7 +53,8 @@ fn test_file() {
     }
   },
   "FOO": "FOO should be overridden",
-  "bar": "I am bar"
+  "bar": "I am bar",
+  "nullable": null
 }
 "#,
             FileFormat::Json,
@@ -92,6 +94,7 @@ fn test_file() {
             "John Smith".to_owned()
         );
     }
+    assert_eq!(s.nullable, None);
 }
 
 #[test]

tests/testsuite/file_json5.rs

@@ -16,6 +16,7 @@ fn test_file() {
         place: Place,
         #[serde(rename = "arr")]
         elements: Vec<String>,
+        nullable: Option<String>,
     }
 
     #[derive(Debug, Deserialize)]
@@ -54,6 +55,7 @@ fn test_file() {
   },
   FOO: "FOO should be overridden",
   bar: "I am bar",
+  nullable: null
 }
 "#,
             FileFormat::Json5,
@@ -93,6 +95,7 @@ fn test_file() {
             "John Smith".to_owned()
         );
     }
+    assert_eq!(s.nullable, None);
 }
 
 #[test]

tests/testsuite/file_ron.rs

@@ -16,6 +16,7 @@ fn test_file() {
         place: Place,
         #[serde(rename = "arr")]
         elements: Vec<String>,
+        nullable: Option<String>,
     }
 
     #[derive(Debug, Deserialize)]
@@ -54,7 +55,8 @@ fn test_file() {
     }
   ),
   FOO: "FOO should be overridden",
-  bar: "I am bar"
+  bar: "I am bar",
+  nullable: None
 )
 "#,
             FileFormat::Ron,
@@ -95,6 +97,7 @@ fn test_file() {
             "John Smith".to_owned()
         );
     }
+    assert_eq!(s.nullable, None);
 }
 
 #[test]

tests/testsuite/file_yaml.rs

@@ -18,6 +18,7 @@ fn test_file() {
         place: Place,
         #[serde(rename = "arr")]
         elements: Vec<String>,
+        nullable: Option<String>,
     }
 
     #[derive(Debug, Deserialize)]
@@ -52,6 +53,7 @@ place:
 # For override tests
 FOO: FOO should be overridden
 bar: I am bar
+nullable: null
 "#,
             FileFormat::Yaml,
         ))
@@ -90,6 +92,7 @@ bar: I am bar
             "John Smith".to_owned()
         );
     }
+    assert_eq!(s.nullable, None);
 }
 
 #[test]