From 756007f438cee52a47f757447149c7744be3208a Mon Sep 17 00:00:00 2001
From: Gris Ge <fge@redhat.com>
Date: Sat, 4 Jan 2025 16:53:11 +0800
Subject: [PATCH] Serializer should always produce YAML end with '\n'

Signed-off-by: Gris Ge <fge@redhat.com>
---
 src/serializer.rs  |  5 ++++-
 src/value.rs       |  2 ++
 tests/to_string.rs | 17 +++++++++++------
 3 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/src/serializer.rs b/src/serializer.rs
index d898f80..11786dc 100644
--- a/src/serializer.rs
+++ b/src/serializer.rs
@@ -59,9 +59,12 @@ where
         ..Default::default()
     };
     value.serialize(&mut serializer)?;
-    if serializer.output.ends_with("\n") {
+    if serializer.output.ends_with("\n\n") {
         serializer.output.pop();
     }
+    if !serializer.output.ends_with("\n") {
+        serializer.output.push('\n');
+    }
     Ok(serializer.output)
 }
 
diff --git a/src/value.rs b/src/value.rs
index 7e1761d..0b7053a 100644
--- a/src/value.rs
+++ b/src/value.rs
@@ -60,6 +60,8 @@ impl YamlValue {
             // The `as_str()` is called to get tag name of enum instead of
             // content.
             Ok(tag.name.as_str())
+        } else if &self.data == &YamlValueData::Null {
+            Ok("")
         } else {
             Err(RmsdError::unexpected_yaml_node_type(
                 format!("Expecting a string, but got {}", &self.data),
diff --git a/tests/to_string.rs b/tests/to_string.rs
index 5bf6f3f..ef34dae 100644
--- a/tests/to_string.rs
+++ b/tests/to_string.rs
@@ -25,7 +25,8 @@ fn test_struct_to_string() -> Result<(), RmsdError> {
         yaml_str,
         r#"uint_a: 129
 str_b: abc
-bool_c: false"#
+bool_c: false
+"#
     );
 
     assert_eq!(rmsd_yaml::from_str::<FooTest>(&yaml_str)?, data);
@@ -37,7 +38,7 @@ fn test_array_to_string() -> Result<(), RmsdError> {
     let data = vec![1u8, 2, 3, 4];
     let yaml_str = rmsd_yaml::to_string_with_opt(&data, Default::default())?;
 
-    assert_eq!(yaml_str, "- 1\n- 2\n- 3\n- 4");
+    assert_eq!(yaml_str, "- 1\n- 2\n- 3\n- 4\n");
 
     assert_eq!(rmsd_yaml::from_str::<Vec<u8>>(&yaml_str)?, data);
     Ok(())
@@ -77,7 +78,8 @@ fn test_array_of_map() -> Result<(), RmsdError> {
   bool_c: false
 - uint_a: 128
   str_b: abd
-  bool_c: true"#
+  bool_c: true
+"#
     );
 
     assert_eq!(rmsd_yaml::from_str::<Vec<FooTest>>(&yaml_str)?, data);
@@ -108,7 +110,8 @@ uint_a:
   - 129
   - 128
   - 127
-str_b: abc"#
+str_b: abc
+"#
     );
 
     assert_eq!(rmsd_yaml::from_str::<FooTest>(&yaml_str)?, data);
@@ -132,7 +135,8 @@ fn test_nested_array() -> Result<(), RmsdError> {
 - - 5
   - 6
   - 7
-  - 8"#
+  - 8
+"#
     );
 
     assert_eq!(rmsd_yaml::from_str::<FooTest>(&yaml_str)?, data);
@@ -171,7 +175,8 @@ bar:
     - 1
     - 2
     - 3
-    - 4"#
+    - 4
+"#
     );
 
     assert_eq!(rmsd_yaml::from_str::<FooTest>(&yaml_str)?, data);