Fix io::BufReader uses of read_buf

a1phyr · a1phyr · commit 57f279d91b7d · 2024-09-23T22:51:27.000+02:00
diff --git a/std/src/io/buffered/bufreader.rs b/std/src/io/buffered/bufreader.rs
@@ -349,7 +349,7 @@ impl<R: ?Sized + Read> Read for BufReader<R> {
         let prev = cursor.written();
 
         let mut rem = self.fill_buf()?;
-        rem.read_buf(cursor.reborrow())?;
+        rem.read_buf(cursor.reborrow())?; // actually never fails
 
         self.consume(cursor.written() - prev); //slice impl of read_buf known to never unfill buf
 
diff --git a/std/src/io/buffered/bufreader/buffer.rs b/std/src/io/buffered/bufreader/buffer.rs
@@ -133,11 +133,13 @@ impl Buffer {
                 buf.set_init(self.initialized);
             }
 
-            reader.read_buf(buf.unfilled())?;
+            let result = reader.read_buf(buf.unfilled());
 
             self.pos = 0;
             self.filled = buf.len();
             self.initialized = buf.init_len();
+
+            result?;
         }
         Ok(self.buffer())
     }

Original file line number	Diff line number	Diff line change
`@@ -133,11 +133,13 @@ impl Buffer {`
`133`	`133`	`buf.set_init(self.initialized);`
`134`	`134`	`}`
`135`	`135`
`136`		`- reader.read_buf(buf.unfilled())?;`
	`136`	`+ let result = reader.read_buf(buf.unfilled());`
`137`	`137`
`138`	`138`	`self.pos = 0;`
`139`	`139`	`self.filled = buf.len();`
`140`	`140`	`self.initialized = buf.init_len();`
	`141`	`+`
	`142`	`+ result?;`
`141`	`143`	`}`
`142`	`144`	`Ok(self.buffer())`
`143`	`145`	`}`