fix: address code review findings from DRY refactoring

- Use std::mem::take() instead of clone() for zero-cost string moves
- Enhance unsafe block documentation with detailed safety invariants
- Add ignore attribute to doc tests for private modules
- Add explicit fn main() wrapper to set_generator doc test

All 315 tests pass, zero clippy warnings.

Author: bug-ops

crates/feedparser-rs-core/src/parser/common.rs

@@ -31,7 +31,7 @@ pub const TEXT_BUFFER_CAPACITY: usize = 256;
 ///
 /// # Examples
 ///
-/// ```
+/// ```ignore
 /// use feedparser_rs_core::parser::common::new_event_buffer;
 ///
 /// let mut buf = new_event_buffer();
@@ -56,7 +56,7 @@ pub fn new_event_buffer() -> Vec<u8> {
 ///
 /// # Examples
 ///
-/// ```
+/// ```ignore
 /// use feedparser_rs_core::parser::common::new_text_buffer;
 ///
 /// let mut text = new_text_buffer();

crates/feedparser-rs-core/src/parser/namespace_detection.rs

@@ -6,7 +6,7 @@
 //!
 //! # Examples
 //!
-//! ```
+//! ```ignore
 //! use feedparser_rs_core::parser::namespace_detection::namespaces;
 //!
 //! let tag_name = b"dc:creator";
@@ -32,7 +32,7 @@ impl NamespacePrefix {
     ///
     /// # Examples
     ///
-    /// ```
+    /// ```ignore
     /// use feedparser_rs_core::parser::namespace_detection::NamespacePrefix;
     ///
     /// const CUSTOM: NamespacePrefix = NamespacePrefix::new("custom:");
@@ -63,7 +63,7 @@ impl NamespacePrefix {
     ///
     /// # Examples
     ///
-    /// ```
+    /// ```ignore
     /// use feedparser_rs_core::parser::namespace_detection::namespaces;
     ///
     /// assert_eq!(namespaces::DC.matches(b"dc:creator"), Some("creator"));
@@ -83,9 +83,19 @@ impl NamespacePrefix {
 
     /// Returns the prefix string (e.g., `"dc:"`)
     ///
+    /// # Safety
+    ///
+    /// This function uses `unsafe` because `std::str::from_utf8` is not
+    /// yet `const fn` stable. The safety invariant is guaranteed by:
+    ///
+    /// 1. `new()` only accepts `&'static str` (compile-time valid UTF-8)
+    /// 2. `as_bytes()` is a reversible, safe transformation
+    /// 3. The field is private and immutable - no external mutation
+    /// 4. All instances are const-initialized with string literals
+    ///
     /// # Examples
     ///
-    /// ```
+    /// ```ignore
     /// use feedparser_rs_core::parser::namespace_detection::namespaces;
     ///
     /// assert_eq!(namespaces::DC.prefix(), "dc:");
@@ -94,7 +104,9 @@ impl NamespacePrefix {
     #[must_use]
     #[allow(dead_code)] // Future use
     pub const fn prefix(&self) -> &'static str {
-        // SAFETY: prefix is constructed from &'static str in new(), always valid UTF-8
+        // SAFETY: prefix is always constructed from &'static str in new(),
+        // which guarantees valid UTF-8. The field is private and immutable,
+        // so no external code can violate this invariant.
         #[allow(unsafe_code)]
         unsafe {
             std::str::from_utf8_unchecked(self.prefix)
@@ -117,7 +129,7 @@ impl NamespacePrefix {
 ///
 /// # Examples
 ///
-/// ```
+/// ```ignore
 /// use feedparser_rs_core::parser::namespace_detection::namespaces;
 ///
 /// let tag = b"itunes:author";

crates/feedparser-rs-core/src/types/entry.rs

@@ -114,8 +114,8 @@ impl Entry {
     /// assert_eq!(entry.title.as_deref(), Some("Great Article"));
     /// ```
     #[inline]
-    pub fn set_title(&mut self, text: TextConstruct) {
-        self.title = Some(text.value.clone());
+    pub fn set_title(&mut self, mut text: TextConstruct) {
+        self.title = Some(std::mem::take(&mut text.value));
         self.title_detail = Some(text);
     }
 
@@ -131,8 +131,8 @@ impl Entry {
     /// assert_eq!(entry.summary.as_deref(), Some("A summary"));
     /// ```
     #[inline]
-    pub fn set_summary(&mut self, text: TextConstruct) {
-        self.summary = Some(text.value.clone());
+    pub fn set_summary(&mut self, mut text: TextConstruct) {
+        self.summary = Some(std::mem::take(&mut text.value));
         self.summary_detail = Some(text);
     }
 
@@ -148,8 +148,8 @@ impl Entry {
     /// assert_eq!(entry.author.as_deref(), Some("Jane Doe"));
     /// ```
     #[inline]
-    pub fn set_author(&mut self, person: Person) {
-        self.author.clone_from(&person.name);
+    pub fn set_author(&mut self, mut person: Person) {
+        self.author = person.name.take();
         self.author_detail = Some(person);
     }
 
@@ -165,8 +165,8 @@ impl Entry {
     /// assert_eq!(entry.publisher.as_deref(), Some("ACME Corp"));
     /// ```
     #[inline]
-    pub fn set_publisher(&mut self, person: Person) {
-        self.publisher.clone_from(&person.name);
+    pub fn set_publisher(&mut self, mut person: Person) {
+        self.publisher = person.name.take();
         self.publisher_detail = Some(person);
     }
 }

crates/feedparser-rs-core/src/types/feed.rs

@@ -265,8 +265,8 @@ impl FeedMeta {
     /// assert_eq!(meta.title.as_deref(), Some("Example Feed"));
     /// ```
     #[inline]
-    pub fn set_title(&mut self, text: TextConstruct) {
-        self.title = Some(text.value.clone());
+    pub fn set_title(&mut self, mut text: TextConstruct) {
+        self.title = Some(std::mem::take(&mut text.value));
         self.title_detail = Some(text);
     }
 
@@ -282,8 +282,8 @@ impl FeedMeta {
     /// assert_eq!(meta.subtitle.as_deref(), Some("A great feed"));
     /// ```
     #[inline]
-    pub fn set_subtitle(&mut self, text: TextConstruct) {
-        self.subtitle = Some(text.value.clone());
+    pub fn set_subtitle(&mut self, mut text: TextConstruct) {
+        self.subtitle = Some(std::mem::take(&mut text.value));
         self.subtitle_detail = Some(text);
     }
 
@@ -299,8 +299,8 @@ impl FeedMeta {
     /// assert_eq!(meta.rights.as_deref(), Some("© 2025 Example"));
     /// ```
     #[inline]
-    pub fn set_rights(&mut self, text: TextConstruct) {
-        self.rights = Some(text.value.clone());
+    pub fn set_rights(&mut self, mut text: TextConstruct) {
+        self.rights = Some(std::mem::take(&mut text.value));
         self.rights_detail = Some(text);
     }
 
@@ -311,18 +311,20 @@ impl FeedMeta {
     /// ```
     /// use feedparser_rs_core::{FeedMeta, Generator};
     ///
+    /// # fn main() {
     /// let mut meta = FeedMeta::default();
-    /// let gen = Generator {
+    /// let generator = Generator {
     ///     value: "Example Generator".to_string(),
     ///     uri: None,
     ///     version: None,
     /// };
-    /// meta.set_generator(gen);
+    /// meta.set_generator(generator);
     /// assert_eq!(meta.generator.as_deref(), Some("Example Generator"));
+    /// # }
     /// ```
     #[inline]
-    pub fn set_generator(&mut self, generator: Generator) {
-        self.generator = Some(generator.value.clone());
+    pub fn set_generator(&mut self, mut generator: Generator) {
+        self.generator = Some(std::mem::take(&mut generator.value));
         self.generator_detail = Some(generator);
     }
 
@@ -338,8 +340,8 @@ impl FeedMeta {
     /// assert_eq!(meta.author.as_deref(), Some("John Doe"));
     /// ```
     #[inline]
-    pub fn set_author(&mut self, person: Person) {
-        self.author.clone_from(&person.name);
+    pub fn set_author(&mut self, mut person: Person) {
+        self.author = person.name.take();
         self.author_detail = Some(person);
     }
 
@@ -355,8 +357,8 @@ impl FeedMeta {
     /// assert_eq!(meta.publisher.as_deref(), Some("ACME Corp"));
     /// ```
     #[inline]
-    pub fn set_publisher(&mut self, person: Person) {
-        self.publisher.clone_from(&person.name);
+    pub fn set_publisher(&mut self, mut person: Person) {
+        self.publisher = person.name.take();
         self.publisher_detail = Some(person);
     }
 }