moved several utils

libp2p/streams/utils.nim

@@ -6,7 +6,7 @@ template toFuture*[T](v: T): Future[T] =
   fut.complete(v)
   fut
 
-template toThrough*[T](s: Stream[T]): Through[T] =
+proc toThrough*[T](s: Stream[T]): Through[T] {.inline.} =
   proc sinkit(i: Source[T]) {.async.} =
     await s.sink()(i)
 
@@ -29,6 +29,12 @@ template pipe*[T](s: Stream[T] | Source[T],
 
 template pipe*[T](s: Stream[T] | Source[T],
                   x: Stream[T] | Sink[T]): Future[void] =
+  var pipeline: Source[T]
+  when s is Source[T]:
+    pipeline = s
+  elif s is Stream[T]:
+    pipeline = s.source
+
   var terminal: Future[void]
   when x is Stream[T]:
     terminal = x.sink()(pipeline)
@@ -41,6 +47,25 @@ template pipe*[T](s: Stream[T] | Source[T],
                   t: varargs[Through[T]],
                   x: Stream[T] | Sink[T]): Future[void] =
   var pipeline = pipe(s, t)
-  pipe(s, x)
+  pipe(pipeline, x)
 
+proc appendNl*(): Through[seq[byte]] =
+  proc append(item: Future[seq[byte]]): Future[seq[byte]] {.async.} =
+    result = await item
+    result.add(byte('\n'))
 
+  return proc(i: Source[seq[byte]]): Source[seq[byte]] {.gcsafe.} =
+    return iterator(): Future[seq[byte]] {.closure.} =
+      for item in i:
+        yield append(item)
+
+proc stripNl*(): Through[seq[byte]] =
+  proc strip(item: Future[seq[byte]]): Future[seq[byte]] {.async.} =
+    result = await item
+    if result.len > 0 and result[^1] == byte('\n'):
+      result.setLen(result.high)
+
+  return proc(i: Source[seq[byte]]): Source[seq[byte]] {.gcsafe.} =
+    return iterator(): Future[seq[byte]] {.closure.} =
+      for item in i:
+        yield strip(item)