all: fix lint suggestions

Signed-off-by: Koichi Shiraishi <zchee.io@gmail.com>

Author: zchee

.golangci.yml

@@ -105,6 +105,7 @@ linters:
     - goerr113          # Golang linter to check the errors handling expressions
     - gofumpt           # Gofumpt checks whether code was gofumpt-ed
     - goheader          # Checks is file header matches to pattern
+    - golint            # Golint differs from gofmt. Gofmt reformats Go source code, whereas golint prints out style mistakes
     - gomnd             # An analyzer to detect magic numbers
     - gomodguard        # Allow and block list linter for direct Go module dependencies
     - gosec             # Inspects source code for security problems
@@ -114,14 +115,16 @@ linters:
     - sqlclosecheck     # Checks that sql.Rows and sql.Stmt are closed
     - wrapcheck         # Checks that errors returned from external packages are wrapped TODO(zchee): enable
     - wsl               # Whitespace Linter
+    # TODO(zchee): enable
+    - deadcode          # Finds unused code
+    - errcheck          # Errcheck is a program for checking for unchecked errors in go programs
+    - unparam           # Reports unused function parameters
   enable:
     - asciicheck        # Simple linter to check that your code does not contain non-ASCII identifiers
     - bodyclose         # checks whether HTTP response body is closed successfully
-    - deadcode          # Finds unused code
     - depguard          # Go linter that checks if package imports are in a list of acceptable packages
     - dogsled           # Checks assignments with too many blank identifiers
     - dupl              # Tool for code clone detection
-    - errcheck          # Errcheck is a program for checking for unchecked errors in go programs
     - errorlint         # source code linter for Go software that can be used to find code that will cause problemswith the error wrapping scheme introduced in Go 1.13
     - exhaustive        # check exhaustiveness of enum switch statements
     - exportloopref     # checks for pointers to enclosing loop variables
@@ -133,7 +136,6 @@ linters:
     - godot             # Check if comments end in a period
     - gofmt             # Gofmt checks whether code was gofmt-ed. By default this tool runs with -s option to check for code simplification
     - goimports         # Goimports does everything that gofmt does. Additionally it checks unused imports
-    - golint            # Golint differs from gofmt. Gofmt reformats Go source code, whereas golint prints out style mistakes
     - goprintffuncname  # Checks that printf-like functions are named with `f` at the end
     - gosimple          # Linter for Go source code that specializes in simplifying a code
     - govet             # Vet examines Go source code and reports suspicious constructs, such as Printf calls whose arguments do not align with the format string
@@ -157,7 +159,6 @@ linters:
     - tparallel         # tparallel detects inappropriate usage of t.Parallel() method in your Go test codes
     - typecheck         # Like the front-end of a Go compiler, parses and type-checks Go code
     - unconvert         # Remove unnecessary type conversions
-    - unparam           # Reports unused function parameters
     - unused            # Checks Go code for unused constants, variables, functions and types
     - varcheck          # Finds unused global variables and constants
     - whitespace        # Tool for detection of leading and trailing whitespace

conn.go

@@ -151,7 +151,7 @@ func (c *conn) Notify(ctx context.Context, method string, params interface{}) (e
 	return err
 }
 
-func (c *conn) replier(req Message, spanDone func()) Replier {
+func (c *conn) replier(req Message) Replier {
 	return func(ctx context.Context, result interface{}, err error) error {
 		call, ok := req.(*Call)
 		if !ok {
@@ -173,9 +173,9 @@ func (c *conn) replier(req Message, spanDone func()) Replier {
 	}
 }
 
-func (c *conn) write(ctx context.Context, msg Message) (n int64, err error) {
+func (c *conn) write(ctx context.Context, msg Message) (int64, error) {
 	c.writeMu.Lock()
-	n, err = c.stream.Write(ctx, msg)
+	n, err := c.stream.Write(ctx, msg)
 	c.writeMu.Unlock()
 	if err != nil {
 		return 0, fmt.Errorf("write to stream: %w", err)
@@ -203,7 +203,9 @@ func (c *conn) run(ctx context.Context, handler Handler) {
 
 		switch msg := msg.(type) {
 		case Request:
-			handler(ctx, c.replier(msg, func() {}), msg)
+			if err := handler(ctx, c.replier(msg), msg); err != nil {
+				c.fail(err)
+			}
 
 		case *Response:
 			// If method is not set, this should be a response, in which case we must

handler.go

@@ -111,7 +111,7 @@ func AsyncHandler(handler Handler) (h Handler) {
 
 		go func() {
 			<-waitForPrevious
-			handler(ctx, reply, req)
+			_ = handler(ctx, reply, req)
 		}()
 		return nil
 	})