Add expand_empty_elements fn to Serializer

Setting this to true will serialize empty elements to <element></element> instead of <element/>.
tafia · Jun 27, 2023 · 1f44bb4 · 1f44bb4
1 parent 60249ae
commit 1f44bb4
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Showing 3 changed files with 53 additions and 1 deletion.
diff --git a/src/se/content.rs b/src/se/content.rs
@@ -56,6 +56,9 @@ pub struct ContentSerializer<'w, 'i, W: Write> {
     /// If `true`, then current indent will be written before writing the content,
     /// but only if content is not empty.
     pub write_indent: bool,
+    // If `true`, then empty elements will be serialized as `<element></element>`
+    // instead of `<element/>`.
+    pub expand_empty_elements: bool,
     //TODO: add settings to disallow consequent serialization of primitives
 }
 
@@ -85,6 +88,7 @@ impl<'w, 'i, W: Write> ContentSerializer<'w, 'i, W> {
             level: self.level,
             indent: self.indent.borrow(),
             write_indent: self.write_indent,
+            expand_empty_elements: false,
         }
     }
 
@@ -483,6 +487,7 @@ pub(super) mod tests {
                         level: QuoteLevel::Full,
                         indent: Indent::None,
                         write_indent: false,
+                        expand_empty_elements: false,
                     };
 
                     $data.serialize(ser).unwrap();
@@ -503,6 +508,7 @@ pub(super) mod tests {
                         level: QuoteLevel::Full,
                         indent: Indent::None,
                         write_indent: false,
+                        expand_empty_elements: false,
                     };
 
                     match $data.serialize(ser).unwrap_err() {
@@ -672,6 +678,7 @@ pub(super) mod tests {
                         level: QuoteLevel::Full,
                         indent: Indent::Owned(Indentation::new(b' ', 2)),
                         write_indent: false,
+                        expand_empty_elements: false,
                     };
 
                     $data.serialize(ser).unwrap();
@@ -692,6 +699,7 @@ pub(super) mod tests {
                         level: QuoteLevel::Full,
                         indent: Indent::Owned(Indentation::new(b' ', 2)),
                         write_indent: false,
+                        expand_empty_elements: false,
                     };
 
                     match $data.serialize(ser).unwrap_err() {

diff --git a/src/se/element.rs b/src/se/element.rs
@@ -66,7 +66,7 @@ impl<'w, 'k, W: Write> Serializer for ElementSerializer<'w, 'k, W> {
     write_primitive!(serialize_bytes(&[u8]));
 
     fn serialize_str(self, value: &str) -> Result<Self::Ok, Self::Error> {
-        if value.is_empty() {
+        if value.is_empty() && !self.ser.expand_empty_elements {
             self.ser.write_empty(self.key)
         } else {
             self.ser
@@ -397,6 +397,7 @@ impl<'w, 'k, W: Write> Struct<'w, 'k, W> {
             level: self.ser.ser.level,
             indent: self.ser.ser.indent.borrow(),
             write_indent: true,
+            expand_empty_elements: false,
         };
 
         if key == TEXT_KEY {
@@ -574,6 +575,7 @@ mod tests {
                             level: QuoteLevel::Full,
                             indent: Indent::None,
                             write_indent: false,
+                            expand_empty_elements: false,
                         },
                         key: XmlName("root"),
                     };
@@ -597,6 +599,7 @@ mod tests {
                             level: QuoteLevel::Full,
                             indent: Indent::None,
                             write_indent: false,
+                            expand_empty_elements: false,
                         },
                         key: XmlName("root"),
                     };
@@ -1533,6 +1536,7 @@ mod tests {
                             level: QuoteLevel::Full,
                             indent: Indent::Owned(Indentation::new(b' ', 2)),
                             write_indent: false,
+                            expand_empty_elements: false,
                         },
                         key: XmlName("root"),
                     };
@@ -1556,6 +1560,7 @@ mod tests {
                             level: QuoteLevel::Full,
                             indent: Indent::Owned(Indentation::new(b' ', 2)),
                             write_indent: false,
+                            expand_empty_elements: false,
                         },
                         key: XmlName("root"),
                     };
@@ -2533,4 +2538,35 @@ mod tests {
                     </root>");
         }
     }
+
+    mod expand_empty_elements {
+        use super::*;
+        use pretty_assertions::assert_eq;
+
+        /// Checks that given `$data` successfully serialized as `$expected`
+        macro_rules! serialize_as {
+            ($name:ident: $data:expr => $expected:expr) => {
+                #[test]
+                fn $name() {
+                    let mut buffer = String::new();
+                    let ser = ElementSerializer {
+                        ser: ContentSerializer {
+                            writer: &mut buffer,
+                            level: QuoteLevel::Full,
+                            indent: Indent::None,
+                            write_indent: false,
+                            expand_empty_elements: true,
+                        },
+                        key: XmlName("root"),
+                    };
+
+                    $data.serialize(ser).unwrap();
+                    assert_eq!(buffer, $expected);
+                }
+            };
+        }
+
+        serialize_as!(option_some_empty: Some("") => "<root></root>");
+        serialize_as!(option_some_empty_str: Some("") => "<root></root>");
+    }
 }
diff --git a/src/se/mod.rs b/src/se/mod.rs
@@ -458,6 +458,7 @@ impl<'w, 'r, W: Write> Serializer<'w, 'r, W> {
                 level: QuoteLevel::Full,
                 indent: Indent::None,
                 write_indent: false,
+                expand_empty_elements: false,
             },
             root_tag: None,
         }
@@ -522,11 +523,18 @@ impl<'w, 'r, W: Write> Serializer<'w, 'r, W> {
                 level: QuoteLevel::Full,
                 indent: Indent::None,
                 write_indent: false,
+                expand_empty_elements: false,
             },
             root_tag: root_tag.map(|tag| XmlName::try_from(tag)).transpose()?,
         })
     }
 
+    /// Enable or disable expansion of empty elements.
+    pub fn expand_empty_elements(&mut self, expand: bool) -> &mut Self {
+        self.ser.expand_empty_elements = expand;
+        self
+    }
+
     /// Configure indent for a serializer
     pub fn indent(&mut self, indent_char: char, indent_size: usize) -> &mut Self {
         self.ser.indent = Indent::Owned(Indentation::new(indent_char as u8, indent_size));