fix tag fields not loading pre-set value correctly

src/main.rs

@@ -3,6 +3,8 @@
 #[macro_use] extern crate rocket;
 #[macro_use] extern crate serde;
 
+use serde_json::json;
+
 //use rocket::request::FromSegments;
 //use rocket::http::uri::Segments;
 use rocket_contrib::serve::StaticFiles;
@@ -28,10 +30,17 @@ struct FormContext<'a> {
 fn index(store : State<RwLock<Store>>) -> Template {
     let rg = store.read();
 
+    let tags = json!(["foo", "bar"]);
+
     let indexes = &rg.index;
     let context = FormContext {
         fields: rg.model.fields.iter().map(|(key, field)| {
-            RenderedField::from_template_field(key, field, None, indexes)
+            let value = if key == "tags" {
+                Some(&tags)
+            } else {
+                None
+            };
+            RenderedField::from_template_field(key, field, value, indexes)
         }).collect()
     };
 

src/store/form.rs

@@ -43,17 +43,9 @@ impl<'a> RenderedField<'a> {
         match &field.kind {
             FieldKind::String => {
                 rendered.kind = "string";
-
-                if let Some(Value::String(s)) = value {
-                    rendered.value = Cow::Borrowed(&s.as_str());
-                }
             }
             FieldKind::Text => {
                 rendered.kind = "text";
-
-                if let Some(Value::String(s)) = value {
-                    rendered.value = Cow::Borrowed(&s.as_str());
-                }
             }
             FieldKind::Bool { default } => {
                 rendered.kind = "bool";
@@ -117,26 +109,11 @@ impl<'a> RenderedField<'a> {
                 let group = enum_group.as_ref().unwrap_or(key);
                 let options = index.free_enums.get(group).unwrap_or(&EMPTY_VEC);
                 rendered.options = Some(options);
-
-                if let Some(Value::String(s)) = value {
-                    rendered.value = Cow::Borrowed(&s.as_str());
-                }
             }
             FieldKind::Tags { options } => {
                 rendered.kind = "tags";
                 rendered.options = Some(options);
 
-                if value.is_some() {
-                    rendered.value = serde_json::from_value::<Vec<String>>(value.unwrap().clone())
-                        .unwrap().join(" ").into();
-                }
-
-                if let Some(Value::Array(items)) = value {
-                    rendered.tags_json = serde_json::to_string(items).unwrap();
-                } else {
-                    rendered.tags_json = "[]".into();
-                };
-
                 rendered.all_tags_json = serde_json::to_string(options).unwrap();
             }
             FieldKind::FreeTags { tag_group } => {
@@ -144,20 +121,33 @@ impl<'a> RenderedField<'a> {
                 let group = tag_group.as_ref().unwrap_or(key);
                 let options = index.free_tags.get(group).unwrap_or(&EMPTY_VEC);
 
-                if value.is_some() {
-                    rendered.value = serde_json::from_value::<Vec<String>>(value.unwrap().clone())
-                        .unwrap().join(" ").into();
-                }
+                rendered.options = Some(options);
+                rendered.all_tags_json = "[]".into();
+            }
+        }
 
-                if let Some(Value::Array(items)) = value {
-                    rendered.tags_json = serde_json::to_string(items).unwrap();
+        // Shared code by multiple variants
+        match field.kind {
+            FieldKind::Text | FieldKind::String => {
+                if let Some(Value::String(s)) = value {
+                    rendered.value = Cow::Borrowed(&s.as_str());
+                }
+            },
+            FieldKind::Enum { .. } | FieldKind::FreeEnum { .. } => {
+                if let Some(Value::String(s)) = value {
+                    rendered.value = Cow::Borrowed(&s.as_str());
+                }
+            },
+            FieldKind::Tags { .. } | FieldKind::FreeTags { .. } => {
+                if let Some(v) = value {
+                    rendered.value = serde_json::from_value::<Vec<String>>(v.clone())
+                        .unwrap().join(" ").into();
+                    rendered.tags_json = serde_json::to_string(v).unwrap();
                 } else {
                     rendered.tags_json = "[]".into();
-                };
-
-                rendered.options = Some(options);
-                rendered.tags_json = serde_json::to_string(options).unwrap();
-            }
+                }
+            },
+            _ => {}
         }
 
         rendered