use Genny to generate typed lists, based on Go standard library code

codecov.yml

@@ -10,6 +10,7 @@ coverage:
     - internal/ackhandler/packet_linkedlist.go
     - internal/utils/byteinterval_linkedlist.go
     - internal/utils/packetinterval_linkedlist.go
+    - internal/utils/linkedlist/linkedlist.go
   status:
     project:
       default:

internal/ackhandler/gen.go

@@ -0,0 +1,3 @@
+package ackhandler
+
+//go:generate genny -pkg ackhandler -in ../utils/linkedlist/linkedlist.go -out packet_linkedlist.go gen Item=Packet

internal/ackhandler/packet.go

@@ -8,7 +8,6 @@ import (
 )
 
 // A Packet is a packet
-// +gen linkedlist
 type Packet struct {
 	PacketNumber    protocol.PacketNumber
 	PacketType      protocol.PacketType

internal/ackhandler/packet_linkedlist.go

@@ -1,13 +1,10 @@
-// Generated by: main
-// TypeWriter: linkedlist
-// Directive: +gen on Packet
+// This file was automatically generated by genny.
+// Any changes will be lost if this file is regenerated.
+// see https://github.com/cheekybits/genny
 
 package ackhandler
 
-// List is a modification of http://golang.org/pkg/container/list/
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
+// Linked list implementation from the Go standard library.
 
 // PacketElement is an element of a linked list.
 type PacketElement struct {
@@ -41,8 +38,7 @@ func (e *PacketElement) Prev() *PacketElement {
 	return nil
 }
 
-// PacketList represents a doubly linked list.
-// The zero value for PacketList is an empty list ready to use.
+// PacketList is a linked list of Packets.
 type PacketList struct {
 	root PacketElement // sentinel list element, only &root, root.prev, and root.next are used
 	len  int           // current list length excluding (this) sentinel element
@@ -63,23 +59,23 @@ func NewPacketList() *PacketList { return new(PacketList).Init() }
 // The complexity is O(1).
 func (l *PacketList) Len() int { return l.len }
 
-// Front returns the first element of list l or nil.
+// Front returns the first element of list l or nil if the list is empty.
 func (l *PacketList) Front() *PacketElement {
 	if l.len == 0 {
 		return nil
 	}
 	return l.root.next
 }
 
-// Back returns the last element of list l or nil.
+// Back returns the last element of list l or nil if the list is empty.
 func (l *PacketList) Back() *PacketElement {
 	if l.len == 0 {
 		return nil
 	}
 	return l.root.prev
 }
 
-// lazyInit lazily initializes a zero PacketList value.
+// lazyInit lazily initializes a zero List value.
 func (l *PacketList) lazyInit() {
 	if l.root.next == nil {
 		l.Init()
@@ -98,7 +94,7 @@ func (l *PacketList) insert(e, at *PacketElement) *PacketElement {
 	return e
 }
 
-// insertValue is a convenience wrapper for insert(&PacketElement{Value: v}, at).
+// insertValue is a convenience wrapper for insert(&Element{Value: v}, at).
 func (l *PacketList) insertValue(v Packet, at *PacketElement) *PacketElement {
 	return l.insert(&PacketElement{Value: v}, at)
 }
@@ -116,10 +112,11 @@ func (l *PacketList) remove(e *PacketElement) *PacketElement {
 
 // Remove removes e from l if e is an element of list l.
 // It returns the element value e.Value.
+// The element must not be nil.
 func (l *PacketList) Remove(e *PacketElement) Packet {
 	if e.list == l {
 		// if e.list == l, l must have been initialized when e was inserted
-		// in l or l == nil (e is a zero PacketElement) and l.remove will crash
+		// in l or l == nil (e is a zero Element) and l.remove will crash
 		l.remove(e)
 	}
 	return e.Value
@@ -139,46 +136,51 @@ func (l *PacketList) PushBack(v Packet) *PacketElement {
 
 // InsertBefore inserts a new element e with value v immediately before mark and returns e.
 // If mark is not an element of l, the list is not modified.
+// The mark must not be nil.
 func (l *PacketList) InsertBefore(v Packet, mark *PacketElement) *PacketElement {
 	if mark.list != l {
 		return nil
 	}
-	// see comment in PacketList.Remove about initialization of l
+	// see comment in List.Remove about initialization of l
 	return l.insertValue(v, mark.prev)
 }
 
 // InsertAfter inserts a new element e with value v immediately after mark and returns e.
 // If mark is not an element of l, the list is not modified.
+// The mark must not be nil.
 func (l *PacketList) InsertAfter(v Packet, mark *PacketElement) *PacketElement {
 	if mark.list != l {
 		return nil
 	}
-	// see comment in PacketList.Remove about initialization of l
+	// see comment in List.Remove about initialization of l
 	return l.insertValue(v, mark)
 }
 
 // MoveToFront moves element e to the front of list l.
 // If e is not an element of l, the list is not modified.
+// The element must not be nil.
 func (l *PacketList) MoveToFront(e *PacketElement) {
 	if e.list != l || l.root.next == e {
 		return
 	}
-	// see comment in PacketList.Remove about initialization of l
+	// see comment in List.Remove about initialization of l
 	l.insert(l.remove(e), &l.root)
 }
 
 // MoveToBack moves element e to the back of list l.
 // If e is not an element of l, the list is not modified.
+// The element must not be nil.
 func (l *PacketList) MoveToBack(e *PacketElement) {
 	if e.list != l || l.root.prev == e {
 		return
 	}
-	// see comment in PacketList.Remove about initialization of l
+	// see comment in List.Remove about initialization of l
 	l.insert(l.remove(e), l.root.prev)
 }
 
 // MoveBefore moves element e to its new position before mark.
 // If e or mark is not an element of l, or e == mark, the list is not modified.
+// The element and mark must not be nil.
 func (l *PacketList) MoveBefore(e, mark *PacketElement) {
 	if e.list != l || e == mark || mark.list != l {
 		return
@@ -187,7 +189,8 @@ func (l *PacketList) MoveBefore(e, mark *PacketElement) {
 }
 
 // MoveAfter moves element e to its new position after mark.
-// If e is not an element of l, or e == mark, the list is not modified.
+// If e or mark is not an element of l, or e == mark, the list is not modified.
+// The element and mark must not be nil.
 func (l *PacketList) MoveAfter(e, mark *PacketElement) {
 	if e.list != l || e == mark || mark.list != l {
 		return
@@ -196,7 +199,7 @@ func (l *PacketList) MoveAfter(e, mark *PacketElement) {
 }
 
 // PushBackList inserts a copy of an other list at the back of list l.
-// The lists l and other may be the same.
+// The lists l and other may be the same. They must not be nil.
 func (l *PacketList) PushBackList(other *PacketList) {
 	l.lazyInit()
 	for i, e := other.Len(), other.Front(); i > 0; i, e = i-1, e.Next() {
@@ -205,7 +208,7 @@ func (l *PacketList) PushBackList(other *PacketList) {
 }
 
 // PushFrontList inserts a copy of an other list at the front of list l.
-// The lists l and other may be the same.
+// The lists l and other may be the same. They must not be nil.
 func (l *PacketList) PushFrontList(other *PacketList) {
 	l.lazyInit()
 	for i, e := other.Len(), other.Back(); i > 0; i, e = i-1, e.Prev() {

internal/utils/byteinterval_linkedlist.go

@@ -1,13 +1,10 @@
-// Generated by: main
-// TypeWriter: linkedlist
-// Directive: +gen on ByteInterval
+// This file was automatically generated by genny.
+// Any changes will be lost if this file is regenerated.
+// see https://github.com/cheekybits/genny
 
 package utils
 
-// List is a modification of http://golang.org/pkg/container/list/
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
+// Linked list implementation from the Go standard library.
 
 // ByteIntervalElement is an element of a linked list.
 type ByteIntervalElement struct {
@@ -41,8 +38,7 @@ func (e *ByteIntervalElement) Prev() *ByteIntervalElement {
 	return nil
 }
 
-// ByteIntervalList represents a doubly linked list.
-// The zero value for ByteIntervalList is an empty list ready to use.
+// ByteIntervalList is a linked list of ByteIntervals.
 type ByteIntervalList struct {
 	root ByteIntervalElement // sentinel list element, only &root, root.prev, and root.next are used
 	len  int                 // current list length excluding (this) sentinel element
@@ -63,23 +59,23 @@ func NewByteIntervalList() *ByteIntervalList { return new(ByteIntervalList).Init
 // The complexity is O(1).
 func (l *ByteIntervalList) Len() int { return l.len }
 
-// Front returns the first element of list l or nil.
+// Front returns the first element of list l or nil if the list is empty.
 func (l *ByteIntervalList) Front() *ByteIntervalElement {
 	if l.len == 0 {
 		return nil
 	}
 	return l.root.next
 }
 
-// Back returns the last element of list l or nil.
+// Back returns the last element of list l or nil if the list is empty.
 func (l *ByteIntervalList) Back() *ByteIntervalElement {
 	if l.len == 0 {
 		return nil
 	}
 	return l.root.prev
 }
 
-// lazyInit lazily initializes a zero ByteIntervalList value.
+// lazyInit lazily initializes a zero List value.
 func (l *ByteIntervalList) lazyInit() {
 	if l.root.next == nil {
 		l.Init()
@@ -98,7 +94,7 @@ func (l *ByteIntervalList) insert(e, at *ByteIntervalElement) *ByteIntervalEleme
 	return e
 }
 
-// insertValue is a convenience wrapper for insert(&ByteIntervalElement{Value: v}, at).
+// insertValue is a convenience wrapper for insert(&Element{Value: v}, at).
 func (l *ByteIntervalList) insertValue(v ByteInterval, at *ByteIntervalElement) *ByteIntervalElement {
 	return l.insert(&ByteIntervalElement{Value: v}, at)
 }
@@ -116,10 +112,11 @@ func (l *ByteIntervalList) remove(e *ByteIntervalElement) *ByteIntervalElement {
 
 // Remove removes e from l if e is an element of list l.
 // It returns the element value e.Value.
+// The element must not be nil.
 func (l *ByteIntervalList) Remove(e *ByteIntervalElement) ByteInterval {
 	if e.list == l {
 		// if e.list == l, l must have been initialized when e was inserted
-		// in l or l == nil (e is a zero ByteIntervalElement) and l.remove will crash
+		// in l or l == nil (e is a zero Element) and l.remove will crash
 		l.remove(e)
 	}
 	return e.Value
@@ -139,46 +136,51 @@ func (l *ByteIntervalList) PushBack(v ByteInterval) *ByteIntervalElement {
 
 // InsertBefore inserts a new element e with value v immediately before mark and returns e.
 // If mark is not an element of l, the list is not modified.
+// The mark must not be nil.
 func (l *ByteIntervalList) InsertBefore(v ByteInterval, mark *ByteIntervalElement) *ByteIntervalElement {
 	if mark.list != l {
 		return nil
 	}
-	// see comment in ByteIntervalList.Remove about initialization of l
+	// see comment in List.Remove about initialization of l
 	return l.insertValue(v, mark.prev)
 }
 
 // InsertAfter inserts a new element e with value v immediately after mark and returns e.
 // If mark is not an element of l, the list is not modified.
+// The mark must not be nil.
 func (l *ByteIntervalList) InsertAfter(v ByteInterval, mark *ByteIntervalElement) *ByteIntervalElement {
 	if mark.list != l {
 		return nil
 	}
-	// see comment in ByteIntervalList.Remove about initialization of l
+	// see comment in List.Remove about initialization of l
 	return l.insertValue(v, mark)
 }
 
 // MoveToFront moves element e to the front of list l.
 // If e is not an element of l, the list is not modified.
+// The element must not be nil.
 func (l *ByteIntervalList) MoveToFront(e *ByteIntervalElement) {
 	if e.list != l || l.root.next == e {
 		return
 	}
-	// see comment in ByteIntervalList.Remove about initialization of l
+	// see comment in List.Remove about initialization of l
 	l.insert(l.remove(e), &l.root)
 }
 
 // MoveToBack moves element e to the back of list l.
 // If e is not an element of l, the list is not modified.
+// The element must not be nil.
 func (l *ByteIntervalList) MoveToBack(e *ByteIntervalElement) {
 	if e.list != l || l.root.prev == e {
 		return
 	}
-	// see comment in ByteIntervalList.Remove about initialization of l
+	// see comment in List.Remove about initialization of l
 	l.insert(l.remove(e), l.root.prev)
 }
 
 // MoveBefore moves element e to its new position before mark.
 // If e or mark is not an element of l, or e == mark, the list is not modified.
+// The element and mark must not be nil.
 func (l *ByteIntervalList) MoveBefore(e, mark *ByteIntervalElement) {
 	if e.list != l || e == mark || mark.list != l {
 		return
@@ -187,7 +189,8 @@ func (l *ByteIntervalList) MoveBefore(e, mark *ByteIntervalElement) {
 }
 
 // MoveAfter moves element e to its new position after mark.
-// If e is not an element of l, or e == mark, the list is not modified.
+// If e or mark is not an element of l, or e == mark, the list is not modified.
+// The element and mark must not be nil.
 func (l *ByteIntervalList) MoveAfter(e, mark *ByteIntervalElement) {
 	if e.list != l || e == mark || mark.list != l {
 		return
@@ -196,7 +199,7 @@ func (l *ByteIntervalList) MoveAfter(e, mark *ByteIntervalElement) {
 }
 
 // PushBackList inserts a copy of an other list at the back of list l.
-// The lists l and other may be the same.
+// The lists l and other may be the same. They must not be nil.
 func (l *ByteIntervalList) PushBackList(other *ByteIntervalList) {
 	l.lazyInit()
 	for i, e := other.Len(), other.Front(); i > 0; i, e = i-1, e.Next() {
@@ -205,7 +208,7 @@ func (l *ByteIntervalList) PushBackList(other *ByteIntervalList) {
 }
 
 // PushFrontList inserts a copy of an other list at the front of list l.
-// The lists l and other may be the same.
+// The lists l and other may be the same. They must not be nil.
 func (l *ByteIntervalList) PushFrontList(other *ByteIntervalList) {
 	l.lazyInit()
 	for i, e := other.Len(), other.Back(); i > 0; i, e = i-1, e.Prev() {

internal/utils/gen.go

@@ -0,0 +1,4 @@
+package utils
+
+//go:generate genny -pkg utils -in linkedlist/linkedlist.go -out byteinterval_linkedlist.go gen Item=ByteInterval
+//go:generate genny -pkg utils -in linkedlist/linkedlist.go -out packetinterval_linkedlist.go gen Item=PacketInterval

internal/utils/linkedlist/README.md

@@ -0,0 +1,11 @@
+# Usage
+
+This is the Go standard library implementation of a linked list 
+(https://golang.org/src/container/list/list.go), modified such that genny
+(https://github.com/cheekybits/genny) can be used to generate a typed linked
+list.
+
+To generate, run
+```
+genny -pkg $PACKAGE -in linkedlist.go -out $OUTFILE gen Item=$TYPE
+```