From 0dd99f9a344d40605005576f37b1c90442f54397 Mon Sep 17 00:00:00 2001
From: Rod S <rsheeter@google.com>
Date: Wed, 23 Aug 2023 21:41:43 -0700
Subject: [PATCH] Try buf.clear

---
 Cargo.toml            |  5 +++++
 benches/glif_parse.rs | 28 +++++++++++++++++++++++++++-
 src/glyph/parse.rs    |  6 ++++++
 3 files changed, 38 insertions(+), 1 deletion(-)

diff --git a/Cargo.toml b/Cargo.toml
index b2802b57..c91c09fb 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -45,6 +45,11 @@ pretty_assertions = "1.0"
 expect-test = "1.4.1"
 criterion = "0.5"
 
+# https://github.com/bheisler/criterion.rs/issues/193
+# Make it possible to save baseline, e.g. cargo bench -- --save-baseline master
+[lib]
+bench = false
+
 [[bench]]
 name = "glif_parse"
 harness = false
diff --git a/benches/glif_parse.rs b/benches/glif_parse.rs
index 0781c221..5c4648ba 100644
--- a/benches/glif_parse.rs
+++ b/benches/glif_parse.rs
@@ -2,19 +2,36 @@
 //!
 //! This should be run when making any changes to glyph parsing.
 
+use std::path::{Path, PathBuf};
+
 use criterion::{black_box, criterion_group, criterion_main, Criterion};
 use norad::Glyph;
 
+static MUTATOR_SANS_GLYPHS_DIR: &str = "testdata/MutatorSansLightWide.ufo/glyphs";
 static S_GLYPH: &str = "testdata/MutatorSansLightWide.ufo/glyphs/S_.glif";
 static DOT: &str = "testdata/MutatorSansLightWide.ufo/glyphs/dot.glif";
 static A_ACUTE_GLYPH: &str = "testdata/MutatorSansLightWide.ufo/glyphs/A_acute.glif";
 // largest glyph in noto cjk
 static CID61855: &str = "testdata/cid61855.glif";
 
-fn load_bytes(path: &str) -> Vec<u8> {
+fn load_bytes<P>(path: P) -> Vec<u8>
+where
+    P: AsRef<Path>,
+{
     std::fs::read(path).unwrap()
 }
 
+fn load_all(dir: &str) -> Vec<(PathBuf, Vec<u8>)> {
+    std::fs::read_dir(dir)
+        .unwrap()
+        .into_iter()
+        .map(|e| e.unwrap())
+        .filter_map(
+            |e| if e.path().is_file() { Some((e.path(), load_bytes(e.path()))) } else { None },
+        )
+        .collect()
+}
+
 pub fn criterion_benchmark(c: &mut Criterion) {
     // a normal glyph
     c.bench_function("parse S", |b| {
@@ -44,6 +61,15 @@ pub fn criterion_benchmark(c: &mut Criterion) {
             Glyph::parse_raw(black_box(&bytes)).unwrap();
         })
     });
+    // many glyphs
+    c.bench_function("parse MutatorSansLightWide glyphs", |b| {
+        let glyphs = load_all(MUTATOR_SANS_GLYPHS_DIR);
+        b.iter(|| {
+            for (_, glyph_bytes) in glyphs.iter().filter(|(p, _)| p.ends_with(".glif")) {
+                Glyph::parse_raw(black_box(&glyph_bytes)).unwrap();
+            }
+        })
+    });
     // Note to somebody using this:
     //
     // It might be nice if we also had some other examples, like a glyph with
diff --git a/src/glyph/parse.rs b/src/glyph/parse.rs
index 7c7b9dd7..52cacb75 100644
--- a/src/glyph/parse.rs
+++ b/src/glyph/parse.rs
@@ -119,6 +119,7 @@ impl<'names> GlifParser<'names> {
                 Event::End(ref end) if end.name().as_ref() == b"glyph" => break,
                 _other => return Err(ErrorKind::MissingCloseTag.into()),
             }
+            buf.clear();
         }
 
         self.glyph.load_object_libs()?;
@@ -158,6 +159,7 @@ impl<'names> GlifParser<'names> {
                 Event::Eof => return Err(ErrorKind::UnexpectedEof.into()),
                 _other => return Err(ErrorKind::UnexpectedElement.into()),
             }
+            buf.clear();
         }
 
         let (mut contours, components) = outline_builder.finish()?;
@@ -235,6 +237,7 @@ impl<'names> GlifParser<'names> {
                 Event::Eof => return Err(ErrorKind::UnexpectedEof.into()),
                 _other => return Err(ErrorKind::UnexpectedElement.into()),
             }
+            buf.clear();
         }
         outline_builder.end_path()?;
 
@@ -302,6 +305,7 @@ impl<'names> GlifParser<'names> {
                 Event::Eof => return Err(ErrorKind::UnexpectedEof.into()),
                 _other => end = reader.buffer_position(),
             }
+            buf.clear();
         }
 
         let plist_slice = &raw_xml[start..end];
@@ -328,6 +332,7 @@ impl<'names> GlifParser<'names> {
                 Event::Eof => return Err(ErrorKind::UnexpectedEof.into()),
                 _other => (),
             }
+            buf.clear();
         }
         Ok(())
     }
@@ -576,5 +581,6 @@ fn start(
             }
             _other => return Err(ErrorKind::WrongFirstElement.into()),
         }
+        buf.clear();
     }
 }