From 140075b58e936c3a03212f9e88a5625b37f75dae Mon Sep 17 00:00:00 2001
From: Aaron Dewes <aaron.dewes@protonmail.com>
Date: Fri, 17 May 2024 21:50:32 +0200
Subject: [PATCH] Improve detecting whether default can be derived

This checks if a struct contains a required member for which `Default` is not implemented (Enums or other structs which don't have `Default`). If it does, Default will not be derived for that struct.

Signed-off-by: Aaron Dewes <aaron.dewes@protonmail.com>
---
 src/main.rs   | 19 ++++++++++---------
 src/output.rs | 30 ++++++++++++++++++++++++++++++
 2 files changed, 40 insertions(+), 9 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index b1037e3..94ddf17 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -246,7 +246,7 @@ impl Kopium {
             }
             self.print_docstr(&s.docs, "");
             if s.is_main_container() {
-                self.print_derives(s);
+                self.print_derives(s, &structs);
                 //root struct gets kube derives unless opted out
                 if !self.hide_kube {
                     println!(
@@ -277,7 +277,7 @@ impl Kopium {
                     println!("pub struct {} {{", s.name);
                 }
             } else {
-                self.print_derives(s);
+                self.print_derives(s, &structs);
                 let spec_trimmed_name = s.name.as_str().replace(&format!("{}Spec", kind), kind);
                 if s.is_enum {
                     println!("pub enum {} {{", spec_trimmed_name);
@@ -338,23 +338,24 @@ impl Kopium {
         }
     }
 
-    fn print_derives(&self, s: &Container) {
+    fn print_derives(&self, s: &Container, containers: &[Container]) {
         let mut derives = vec!["Serialize", "Deserialize", "Clone", "Debug"];
 
         if s.is_main_container() && !self.hide_kube {
             // CustomResource first for root struct
             derives.insert(0, "CustomResource");
         }
-        if self.builders {
+
+        // TypedBuilder does not work with enums
+        if self.builders && !s.is_enum {
             derives.push("TypedBuilder");
         }
 
         for derive in &self.derive {
-            if s.is_enum && derive.derived_trait == "Default" {
-                // Need to drop Default from enum as this cannot be derived.
-                // Enum defaults need to either be manually derived
-                // or we can insert enum defaults
-                continue;
+            if derive.derived_trait == "Default" {
+                if !s.can_derive_default(containers) {
+                    continue;
+                }
             }
 
             if derive.is_applicable_to(s) && !derives.contains(&derive.derived_trait.as_str()) {
diff --git a/src/output.rs b/src/output.rs
index fb25e07..daabbe0 100644
--- a/src/output.rs
+++ b/src/output.rs
@@ -80,6 +80,36 @@ impl Container {
     pub fn contains_conditions(&self) -> bool {
         self.members.iter().any(|m| m.type_.contains("Vec<Condition>"))
     }
+
+    pub fn can_derive_default(&self, containers: &[Container]) -> bool {
+        if self.is_enum {
+            // Need to drop Default from enum as this cannot be derived.
+            // Enum defaults need to either be manually derived
+            // or we can insert enum defaults
+            return false;
+        }
+
+        for m in &self.members {
+            if !m.type_.contains('<')
+                && !m.type_.contains("::")
+                && m.type_ != "String"
+                && m.type_ != "IntOrString"
+                && m.type_ != "NaiveDate"
+                && m.type_ != "DateTime"
+                && m.type_.chars().next().unwrap_or_default().is_uppercase()
+            {
+                if containers
+                    .iter()
+                    .find(|c| c.name == m.type_)
+                    .is_some_and(|c| !c.can_derive_default(containers))
+                {
+                    return false;
+                }
+            }
+        }
+
+        true
+    }
 }
 
 impl Container {