do not implement DerefMut

src/buf.rs

@@ -1,5 +1,5 @@
 use super::Primitive;
-use std::ops::{Deref, DerefMut};
+use std::ops::Deref;
 
 /// Track the limits of data types used in a buffer.
 #[derive(Clone, PartialEq, Debug, Default)]
@@ -87,39 +87,33 @@ impl Limits {
 /// A buffer of arbitrary PDF content.
 #[derive(Clone, PartialEq, Debug)]
 pub struct Buf {
-    buf: Vec<u8>,
+    pub(crate) inner: Vec<u8>,
     pub(crate) limits: Limits,
 }
 
 impl Deref for Buf {
     type Target = Vec<u8>;
 
     fn deref(&self) -> &Self::Target {
-        &self.buf
-    }
-}
-
-impl DerefMut for Buf {
-    fn deref_mut(&mut self) -> &mut Self::Target {
-        &mut self.buf
+        &self.inner
     }
 }
 
 impl Buf {
     pub(crate) fn new() -> Self {
-        Self { buf: Vec::new(), limits: Limits::new() }
+        Self { inner: Vec::new(), limits: Limits::new() }
     }
 
     pub(crate) fn with_capacity(capacity: usize) -> Self {
         Self {
-            buf: Vec::with_capacity(capacity),
+            inner: Vec::with_capacity(capacity),
             limits: Limits::new(),
         }
     }
 
     /// Get the underlying bytes of the buffer.
     pub fn to_bytes(self) -> Vec<u8> {
-        self.buf
+        self.inner
     }
 
     /// Return the limits of the buffer.
@@ -160,7 +154,7 @@ impl Buf {
             #[inline(never)]
             fn write_extreme(buf: &mut Buf, value: f32) {
                 use std::io::Write;
-                write!(buf, "{}", value).unwrap();
+                write!(buf.inner, "{}", value).unwrap();
             }
 
             write_extreme(self, value);
@@ -169,18 +163,18 @@ impl Buf {
 
     #[inline]
     pub(crate) fn extend_slice(&mut self, other: &[u8]) {
-        self.buf.extend(other);
+        self.inner.extend(other);
     }
 
     #[inline]
     pub(crate) fn extend(&mut self, other: &Buf) {
         self.limits.merge(&other.limits);
-        self.buf.extend(&other.buf);
+        self.inner.extend(&other.inner);
     }
 
     #[inline]
     pub(crate) fn push(&mut self, b: u8) {
-        self.buf.push(b);
+        self.inner.push(b);
     }
 
     #[inline]
@@ -213,4 +207,9 @@ impl Buf {
         self.push(octal((value >> 3) & 7));
         self.push(octal(value & 7));
     }
+
+    #[inline]
+    pub(crate) fn reserve(&mut self, additional: usize) {
+        self.inner.reserve(additional)
+    }
 }

src/content.rs

@@ -30,7 +30,7 @@ impl Content {
     /// Return the raw constructed byte stream.
     pub fn finish(mut self) -> Buf {
         if self.buf.last() == Some(&b'\n') {
-            self.buf.pop();
+            self.buf.inner.pop();
         }
         self.buf
     }

src/font.rs

@@ -991,7 +991,7 @@ where
         }
 
         self.count = 0;
-        self.mappings.clear();
+        self.mappings.inner.clear();
     }
 }
 

src/functions.rs

@@ -351,7 +351,7 @@ impl<'a> PostScriptOp<'a> {
             buf.push(b' ');
         }
         if ops.len() == 1 {
-            buf.pop();
+            buf.inner.pop();
         }
         buf.push(b'}');
     }

src/lib.rs

@@ -241,7 +241,7 @@ impl Pdf {
     ///
     /// _Default value_: \x80\x80\x80\x80
     pub fn set_binary_marker(&mut self, marker: &[u8; 4]) {
-        self.chunk.buf[10..14].copy_from_slice(marker);
+        self.chunk.buf.inner[10..14].copy_from_slice(marker);
     }
 
     /// Set the PDF version.
@@ -252,10 +252,10 @@ impl Pdf {
     /// _Default value_: 1.7.
     pub fn set_version(&mut self, major: u8, minor: u8) {
         if major < 10 {
-            self.chunk.buf[5] = b'0' + major;
+            self.chunk.buf.inner[5] = b'0' + major;
         }
         if minor < 10 {
-            self.chunk.buf[7] = b'0' + minor;
+            self.chunk.buf.inner[7] = b'0' + minor;
         }
     }
 
@@ -305,7 +305,7 @@ impl Pdf {
         buf.push(b'\n');
 
         if offsets.is_empty() {
-            write!(buf, "0000000000 65535 f\r\n").unwrap();
+            write!(buf.inner, "0000000000 65535 f\r\n").unwrap();
         }
 
         let mut written = 0;
@@ -330,11 +330,11 @@ impl Pdf {
                 }
 
                 let gen = if free_id == 0 { "65535" } else { "00000" };
-                write!(buf, "{:010} {} f\r\n", next % xref_len, gen).unwrap();
+                write!(buf.inner, "{:010} {} f\r\n", next % xref_len, gen).unwrap();
                 written += 1;
             }
 
-            write!(buf, "{:010} 00000 n\r\n", offset).unwrap();
+            write!(buf.inner, "{:010} 00000 n\r\n", offset).unwrap();
             written += 1;
         }
 
@@ -362,7 +362,7 @@ impl Pdf {
 
         // Write where the cross-reference table starts.
         buf.extend_slice(b"\nstartxref\n");
-        write!(buf, "{}", xref_offset).unwrap();
+        write!(buf.inner, "{}", xref_offset).unwrap();
 
         // Write the end of file marker.
         buf.extend_slice(b"\n%%EOF");

src/object.rs

@@ -79,7 +79,7 @@ impl Primitive for Str<'_> {
         // - Hex strings for anything non-ASCII.
         if self.0.iter().all(|b| b.is_ascii()) {
             buf.reserve(self.0.len());
-            buf.push(b'(');
+            buf.inner.push(b'(');
 
             let mut balanced = None;
             for &byte in self.0 {
@@ -403,17 +403,17 @@ impl Primitive for Date {
         buf.extend_slice(b"(D:");
 
         (|| {
-            write!(buf, "{:04}", self.year).unwrap();
-            write!(buf, "{:02}", self.month?).unwrap();
-            write!(buf, "{:02}", self.day?).unwrap();
-            write!(buf, "{:02}", self.hour?).unwrap();
-            write!(buf, "{:02}", self.minute?).unwrap();
-            write!(buf, "{:02}", self.second?).unwrap();
+            write!(buf.inner, "{:04}", self.year).unwrap();
+            write!(buf.inner, "{:02}", self.month?).unwrap();
+            write!(buf.inner, "{:02}", self.day?).unwrap();
+            write!(buf.inner, "{:02}", self.hour?).unwrap();
+            write!(buf.inner, "{:02}", self.minute?).unwrap();
+            write!(buf.inner, "{:02}", self.second?).unwrap();
             let utc_offset_hour = self.utc_offset_hour?;
             if utc_offset_hour == 0 && self.utc_offset_minute == 0 {
                 buf.push(b'Z');
             } else {
-                write!(buf, "{:+03}'{:02}", utc_offset_hour, self.utc_offset_minute)
+                write!(buf.inner, "{:+03}'{:02}", utc_offset_hour, self.utc_offset_minute)
                     .unwrap();
             }
             Some(())