Use try_reserve instead of with_capacity to handle error

rust-ethereum · Apr 13, 2023 · fa299d8 · fa299d8
1 parent 23a0f85
commit fa299d8
Showing 1 changed file with 23 additions and 23 deletions.
diff --git a/ethabi/src/decoder.rs b/ethabi/src/decoder.rs
@@ -48,17 +48,16 @@ fn decode_impl(types: &[ParamType], data: &[u8], validate: bool) -> Result<(Vec<
 		));
 	}
 
-	let mut offset = 0;
+	let mut tokens = vec![];
+	tokens.try_reserve_exact(types.len()).map_err(|_| Error::InvalidData)?;
 
-	let tokens = types
-		.iter()
-		.map(|param| {
-			let res = decode_param(param, data, offset, validate)?;
-			offset = res.new_offset;
-			Ok(res.token)
-		})
-		.collect::<Result<Vec<Token>, Error>>()?;
+	let mut offset = 0;
 
+	for param in types {
+		let res = decode_param(param, data, offset, validate)?;
+		offset = res.new_offset;
+		tokens.push(res.token);
+	}
 	if validate && offset != data.len() {
 		return Err(Error::InvalidData);
 	}
@@ -180,15 +179,15 @@ fn decode_param(param: &ParamType, data: &[u8], offset: usize, validate: bool) -
 			let tail_offset = len_offset + 32;
 			let tail = &data[tail_offset..];
 
+			let mut tokens = vec![];
+			tokens.try_reserve_exact(len).map_err(|_| Error::InvalidData)?;
 			let mut new_offset = 0;
 
-			let tokens = (0..len)
-				.map(|_| {
-					let res = decode_param(t, tail, new_offset, validate)?;
-					new_offset = res.new_offset;
-					Ok(res.token)
-				})
-				.collect::<Result<Vec<Token>, Error>>()?;
+			for _ in 0..len {
+				let res = decode_param(t, tail, new_offset, validate)?;
+				new_offset = res.new_offset;
+				tokens.push(res.token);
+			}
 
 			let result = DecodeResult { token: Token::Array(tokens), new_offset: offset + 32 };
 
@@ -207,13 +206,14 @@ fn decode_param(param: &ParamType, data: &[u8], offset: usize, validate: bool) -
 				(data, offset)
 			};
 
-			let tokens = (0..len)
-				.map(|_| {
-					let res = decode_param(t, tail, new_offset, validate)?;
-					new_offset = res.new_offset;
-					Ok(res.token)
-				})
-				.collect::<Result<Vec<Token>, Error>>()?;
+			let mut tokens = vec![];
+			tokens.try_reserve_exact(len).map_err(|_| Error::InvalidData)?;
+
+			for _ in 0..len {
+				let res = decode_param(t, tail, new_offset, validate)?;
+				new_offset = res.new_offset;
+				tokens.push(res.token);
+			}
 
 			let result = DecodeResult {
 				token: Token::FixedArray(tokens),