de-dup escaping logic

Author: yotamofek

src/librustdoc/html/escape.rs

@@ -7,37 +7,41 @@ use std::fmt;
 
 use unicode_segmentation::UnicodeSegmentation;
 
+#[inline(always)]
+fn escape(s: &str, mut w: impl fmt::Write, escape_quotes: bool) -> fmt::Result {
+    // Because the internet is always right, turns out there's not that many
+    // characters to escape: http://stackoverflow.com/questions/7381974
+    let pile_o_bits = s;
+    let mut last = 0;
+    for (i, ch) in s.char_indices() {
+        let s = match ch {
+            '>' => ">",
+            '<' => "&lt;",
+            '&' => "&amp;",
+            '\'' if escape_quotes => "&#39;",
+            '"' if escape_quotes => "&quot;",
+            _ => continue,
+        };
+        w.write_str(&pile_o_bits[last..i])?;
+        w.write_str(s)?;
+        // NOTE: we only expect single byte characters here - which is fine as long as we
+        // only match single byte characters
+        last = i + 1;
+    }
+
+    if last < s.len() {
+        w.write_str(&pile_o_bits[last..])?;
+    }
+    Ok(())
+}
+
 /// Wrapper struct which will emit the HTML-escaped version of the contained
 /// string when passed to a format string.
 pub(crate) struct Escape<'a>(pub &'a str);
 
 impl fmt::Display for Escape<'_> {
     fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
-        // Because the internet is always right, turns out there's not that many
-        // characters to escape: http://stackoverflow.com/questions/7381974
-        let Escape(s) = *self;
-        let pile_o_bits = s;
-        let mut last = 0;
-        for (i, ch) in s.char_indices() {
-            let s = match ch {
-                '>' => "&gt;",
-                '<' => "&lt;",
-                '&' => "&amp;",
-                '\'' => "&#39;",
-                '"' => "&quot;",
-                _ => continue,
-            };
-            fmt.write_str(&pile_o_bits[last..i])?;
-            fmt.write_str(s)?;
-            // NOTE: we only expect single byte characters here - which is fine as long as we
-            // only match single byte characters
-            last = i + 1;
-        }
-
-        if last < s.len() {
-            fmt.write_str(&pile_o_bits[last..])?;
-        }
-        Ok(())
+        escape(self.0, fmt, true)
     }
 }
 
@@ -51,29 +55,7 @@ pub(crate) struct EscapeBodyText<'a>(pub &'a str);
 
 impl fmt::Display for EscapeBodyText<'_> {
     fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
-        // Because the internet is always right, turns out there's not that many
-        // characters to escape: http://stackoverflow.com/questions/7381974
-        let EscapeBodyText(s) = *self;
-        let pile_o_bits = s;
-        let mut last = 0;
-        for (i, ch) in s.char_indices() {
-            let s = match ch {
-                '>' => "&gt;",
-                '<' => "&lt;",
-                '&' => "&amp;",
-                _ => continue,
-            };
-            fmt.write_str(&pile_o_bits[last..i])?;
-            fmt.write_str(s)?;
-            // NOTE: we only expect single byte characters here - which is fine as long as we
-            // only match single byte characters
-            last = i + 1;
-        }
-
-        if last < s.len() {
-            fmt.write_str(&pile_o_bits[last..])?;
-        }
-        Ok(())
+        escape(self.0, fmt, false)
     }
 }