fasta/io/writer: Add additional methods to get the underlying writer

noodles-fasta/CHANGELOG.md

@@ -1,5 +1,12 @@
 # Changelog
 
+## Unreleased
+
+### Added
+
+  * fasta/io/writer: Add additional methods to get the underlying writer
+    (`Writer::get_mut` and `Writer::into_inner`).
+
 ## 0.41.0 - 2024-07-14
 
 ### Added

noodles-fasta/src/io/writer.rs

@@ -15,33 +15,64 @@ pub struct Writer<W> {
     line_base_count: usize,
 }
 
-impl<W> Writer<W>
-where
-    W: Write,
-{
-    /// Creates a FASTA writer.
+impl<W> Writer<W> {
+    /// Returns a reference to the underlying writer.
     ///
     /// # Examples
     ///
     /// ```
+    /// # use std::io;
     /// use noodles_fasta as fasta;
-    /// let writer = fasta::io::Writer::new(Vec::new());
+    /// let writer = fasta::io::Writer::new(io::sink());
+    /// let _inner = writer.get_ref();
     /// ```
-    pub fn new(inner: W) -> Self {
-        Builder::default().build_with_writer(inner)
+    pub fn get_ref(&self) -> &W {
+        &self.inner
     }
 
-    /// Returns a reference to the underlying writer.
+    /// Returns a mutable reference to the underlying writer.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// # use std::io;
+    /// use noodles_fasta as fasta;
+    /// let mut writer = fasta::io::Writer::new(io::sink());
+    /// let _inner = writer.get_mut();
+    /// ```
+    pub fn get_mut(&mut self) -> &mut W {
+        &mut self.inner
+    }
+
+    /// Unwraps and returns the underlying writer.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// # use std::io;
+    /// use noodles_fasta as fasta;
+    /// let writer = fasta::io::Writer::new(io::sink());
+    /// let _inner = writer.into_inner();
+    /// ```
+    pub fn into_inner(self) -> W {
+        self.inner
+    }
+}
+
+impl<W> Writer<W>
+where
+    W: Write,
+{
+    /// Creates a FASTA writer.
     ///
     /// # Examples
     ///
     /// ```
     /// use noodles_fasta as fasta;
     /// let writer = fasta::io::Writer::new(Vec::new());
-    /// assert!(writer.get_ref().is_empty());
     /// ```
-    pub fn get_ref(&self) -> &W {
-        &self.inner
+    pub fn new(inner: W) -> Self {
+        Builder::default().build_with_writer(inner)
     }
 
     /// Writes a FASTA record.