Quote args containing spaces in ArgsStringOrList

When ArgsStringOrList::List elements contain spaces, they are now
wrapped in double quotes before joining. This prevents the debugger
from splitting paths with spaces into multiple arguments.

Add tests covering list with spaces, list without spaces, single
element with spaces, empty list, and single string passthrough.

Author: Riccardo Strina

src/util.rs

@@ -414,7 +414,7 @@ pub fn should_use_local_or_download(
 /// A type that can be deserialized from either a single string or a list of strings.
 ///
 /// When serialized, it always produces a single string. If it was a list,
-/// the elements are joined with a space.
+/// the elements are joined with a space, quoting elements that contain spaces.
 #[derive(Deserialize, Debug, Clone)]
 #[serde(untagged)]
 pub enum ArgsStringOrList {
@@ -429,7 +429,71 @@ impl Serialize for ArgsStringOrList {
     {
         match self {
             ArgsStringOrList::String(s) => serializer.serialize_str(s),
-            ArgsStringOrList::List(l) => serializer.serialize_str(&l.join(" ")),
+            ArgsStringOrList::List(l) => {
+                let quoted: Vec<String> = l
+                    .iter()
+                    .map(|s| if s.contains(' ') { format!("\"{}\"", s) } else { s.clone() })
+                    .collect();
+                serializer.serialize_str(&quoted.join(" "))
+            }
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use serde_json;
+
+    #[derive(Deserialize, Serialize)]
+    struct ArgsWrapper {
+        args: ArgsStringOrList,
+    }
+
+    #[test]
+    fn test_args_list_with_spaces_quotes_elements() {
+        let json = std::fs::read_to_string("testdata/args_with_spaces.json").unwrap();
+        let wrapper: ArgsWrapper = serde_json::from_str(&json).unwrap();
+        let serialized = serde_json::to_value(&wrapper).unwrap();
+        assert_eq!(
+            serialized["args"],
+            r#""C:\path with spaces\some file.txt" arg2"#
+        );
+    }
+
+    #[test]
+    fn test_args_single_string_preserved_as_is() {
+        let json = std::fs::read_to_string("testdata/args_single_string.json").unwrap();
+        let wrapper: ArgsWrapper = serde_json::from_str(&json).unwrap();
+        let serialized = serde_json::to_value(&wrapper).unwrap();
+        assert_eq!(
+            serialized["args"],
+            r#"C:\path with spaces\some file.txt"#
+        );
+    }
+
+    #[test]
+    fn test_args_list_no_spaces_not_quoted() {
+        let json = std::fs::read_to_string("testdata/args_list_no_spaces.json").unwrap();
+        let wrapper: ArgsWrapper = serde_json::from_str(&json).unwrap();
+        let serialized = serde_json::to_value(&wrapper).unwrap();
+        assert_eq!(serialized["args"], "arg1 arg2");
+    }
+
+    #[test]
+    fn test_args_single_element_with_spaces_quoted() {
+        let json =
+            std::fs::read_to_string("testdata/args_single_element_with_spaces.json").unwrap();
+        let wrapper: ArgsWrapper = serde_json::from_str(&json).unwrap();
+        let serialized = serde_json::to_value(&wrapper).unwrap();
+        assert_eq!(serialized["args"], r#""path with spaces""#);
+    }
+
+    #[test]
+    fn test_args_empty_list() {
+        let json = std::fs::read_to_string("testdata/args_empty_list.json").unwrap();
+        let wrapper: ArgsWrapper = serde_json::from_str(&json).unwrap();
+        let serialized = serde_json::to_value(&wrapper).unwrap();
+        assert_eq!(serialized["args"], "");
+    }
+}

testdata/args_empty_list.json

@@ -0,0 +1,3 @@
+{
+  "args": []
+}

testdata/args_list_no_spaces.json

@@ -0,0 +1,3 @@
+{
+  "args": ["arg1", "arg2"]
+}

testdata/args_single_element_with_spaces.json

@@ -0,0 +1,3 @@
+{
+  "args": ["path with spaces"]
+}

testdata/args_single_string.json

@@ -0,0 +1,3 @@
+{
+  "args": "C:\\path with spaces\\some file.txt"
+}

testdata/args_with_spaces.json

@@ -0,0 +1,3 @@
+{
+  "args": ["C:\\path with spaces\\some file.txt", "arg2"]
+}