perf: skip while (#24)

* refactor bench to return parsed value

* use `for ... { ... by += 1 ... }` instead of `.iter().take_while(...).count()`

package/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name          = "byte_reader"
-version       = "3.1.0"
+version       = "3.1.1"
 edition       = "2021"
 authors       = ["kanarus <[email protected]>"]
 documentation = "https://docs.rs/byte_reader"

package/src/lib.rs

@@ -80,7 +80,9 @@ impl<'r> Reader<'r> {
 
     /// Skip next byte while `condition` holds on it
     #[inline] pub fn skip_while(&mut self, condition: impl Fn(&u8)->bool) {
-        let by = self.remaining().iter().take_while(|b| condition(b)).count();
+        let mut by = 0; for b in self.remaining() {
+            if condition(b) {by += 1} else {break}
+        }
         self.advance_unchecked_by(by)
     }
     /// `skip_while(u8::is_ascii_whitespace)`

test/benches/prisma.rs

@@ -16,19 +16,26 @@ datasource db {
 #[bench] fn read_a_schema_dot_prisma(b: &mut test::Bencher) {
     use prisma::*;
 
-    b.iter(|| for _ in 0..10 {
-        let mut r = byte_reader::Reader::new(SCHEMA.as_bytes());
-        assert_eq!(Schema::parse(&mut r), Schema {
-            generator_client: GeneratorClient {
-                provider: "qujila",
-                output:   "../src/my_db_module",
-            },
-            datasource: Datasouce {
-                name:     "db",
-                provider: "postgresql",
-                url:      "DATABASE_URL",
-            }
-        })
+    let mut r = byte_reader::Reader::new(SCHEMA.as_bytes());
+    assert_eq!(Schema::parse(&mut r), Schema {
+        generator_client: GeneratorClient {
+            provider: "qujila",
+            output:   "../src/my_db_module",
+        },
+        datasource: Datasouce {
+            name:     "db",
+            provider: "postgresql",
+            url:      "DATABASE_URL",
+        }
+    });
+
+    b.iter(|| {
+        let mut buf = Vec::with_capacity(10);
+        for _ in 0..10 {
+            let mut r = byte_reader::Reader::new(SCHEMA.as_bytes());
+            buf.push(Schema::parse(&mut r))
+        }
+        buf
     })
 }