.golangci: update linter rules

.golangci.yml

@@ -15,23 +15,42 @@ linters-settings:
   govet:
     # Don't report about shadowed variables
     check-shadowing: false
+
   gofmt:
     # simplify code: gofmt with `-s` option, true by default
     simplify: true
+
   funlen:
     # Checks the number of lines in a function.
     # If lower than 0, disable the check.
     lines: 200
     # Checks the number of statements in a function.
     statements: 80
+
   gosec:
     excludes:
       - G402 # Look for bad TLS connection settings.
       - G306 # Poor file permissions used when writing to a new file.
 
+  whitespace:
+    multi-func: true
+    multi-if: true
+
 linters:
   enable-all: true
   disable:
+    # Allow dynamic errors.
+    - goerr113
+
+    # We want to allow short variable names.
+    - varnamelen
+
+    # Allow tests to be put in the same package.
+    - testpackage
+
+    # We want to allow TODOs.
+    - godox
+
     # Init functions are used by loggers throughout the codebase.
     - gochecknoinits
 
@@ -46,6 +65,17 @@ linters:
     # instances are created.
     - exhaustruct
 
+    # Disable gofumpt as it has weird behavior regarding formatting multiple
+    # lines for a function which is in conflict with our contribution
+    # guidelines. See https://github.com/mvdan/gofumpt/issues/235.
+    - gofumpt
+
+    # Disable whitespace linter as it has conflict rules against our
+    # contribution guidelines. See https://github.com/bombsimon/wsl/issues/109.
+    #
+    # TODO: bring it back when the above issue is fixed.
+    - wsl
+
     # Deprecated linters. See https://golangci-lint.run/usage/linters/.
     - interfacer
     - golint

gbn/gbn_client.go

@@ -41,13 +41,13 @@ func NewClientConn(ctx context.Context, n uint8, sendFunc sendBytesFunc,
 
 // clientHandshake initiates the client side GBN handshake.
 // The handshake sequence from the client side is as follows:
-// 1.  The client sends SYN to the server along with the N value that the
-//     client wishes to use for the connection.
-// 2.  The client then waits for the server to respond with SYN.
-// 3a. If the client receives SYN from the server then the client sends back
-//     SYNACK.
+// 1. The client sends SYN to the server along with the N value that the
+// client wishes to use for the connection.
+// 2. The client then waits for the server to respond with SYN.
+// 3a. If the client receives SYN from the server, then the client sends back
+// SYNACK.
 // 3b. If the client does not receive SYN from the server within a given
-//     timeout, then the client restarts the handshake from step 1.
+// timeout, then the client restarts the handshake from step 1.
 func (g *GoBackNConn) clientHandshake() error {
 	// Spin off the recv function in a goroutine so that we can use
 	// a select to choose to timeout waiting for data from the receive
@@ -94,7 +94,10 @@ func (g *GoBackNConn) clientHandshake() error {
 		}
 	}()
 
-	var resp Message
+	var (
+		resp    Message
+		respSYN *PacketSYN
+	)
 handshake:
 	for {
 		// start Handshake
@@ -142,8 +145,10 @@ handshake:
 			}
 
 			log.Debugf("Client got %T", resp)
-			switch resp.(type) {
+			switch r := resp.(type) {
 			case *PacketSYN:
+				respSYN = r
+
 				break handshake
 			default:
 			}
@@ -155,7 +160,8 @@ handshake:
 	}
 
 	log.Debugf("Client got SYN")
-	if resp.(*PacketSYN).N != g.n {
+
+	if respSYN.N != g.n {
 		return io.EOF
 	}
 

gbn/gbn_conn.go

@@ -97,7 +97,7 @@ type GoBackNConn struct {
 	pongTicker *IntervalAwareForceTicker
 	pongWait   chan struct{}
 
-	ctx    context.Context
+	ctx    context.Context //nolint:containedctx
 	cancel func()
 
 	// remoteClosed is closed if the remote party initiated the FIN sequence.

mailbox/server.go

@@ -26,7 +26,7 @@ type Server struct {
 
 	sid [64]byte
 
-	ctx context.Context
+	ctx context.Context //nolint:containedctx
 
 	quit   chan struct{}
 	cancel func()