fix(inline handlers): panic on invalid argument

Author: samber

handler_inline.go

@@ -11,6 +11,13 @@ func NewInlineHandler(
 	enabledFunc func(ctx context.Context, groups []string, attrs []slog.Attr, level slog.Level) bool,
 	handleFunc func(ctx context.Context, groups []string, attrs []slog.Attr, record slog.Record) error,
 ) slog.Handler {
+	if enabledFunc == nil {
+		panic("slog-multi: enabledFunc is required")
+	}
+	if handleFunc == nil {
+		panic("slog-multi: handleFunc is required")
+	}
+
 	return &InlineHandler{
 		groups:      []string{},
 		attrs:       []slog.Attr{},

middleware_inline.go

@@ -14,6 +14,22 @@ func NewInlineMiddleware(
 	withGroupFunc func(name string, next func(string) slog.Handler) slog.Handler,
 ) Middleware {
 	return func(next slog.Handler) slog.Handler {
+		if next == nil {
+			panic("slog-multi: next is required")
+		}
+		if enabledFunc == nil {
+			panic("slog-multi: enabledFunc is required")
+		}
+		if handleFunc == nil {
+			panic("slog-multi: handleFunc is required")
+		}
+		if withAttrsFunc == nil {
+			panic("slog-multi: withAttrsFunc is required")
+		}
+		if withGroupFunc == nil {
+			panic("slog-multi: withGroupFunc is required")
+		}
+
 		return &InlineMiddleware{
 			next:          next,
 			enabledFunc:   enabledFunc,

middleware_inline_enabled.go

@@ -9,6 +9,13 @@ import (
 // NewEnabledInlineMiddleware is shortcut to a middleware that implements only the `Enable` method.
 func NewEnabledInlineMiddleware(enabledFunc func(ctx context.Context, level slog.Level, next func(context.Context, slog.Level) bool) bool) Middleware {
 	return func(next slog.Handler) slog.Handler {
+		if enabledFunc == nil {
+			panic("slog-multi: enabledFunc is required")
+		}
+		if next == nil {
+			panic("slog-multi: next is required")
+		}
+
 		return &EnabledInlineMiddleware{
 			next:        next,
 			enabledFunc: enabledFunc,

middleware_inline_handle.go

@@ -9,6 +9,13 @@ import (
 // NewHandleInlineMiddleware is a shortcut to a middleware that implements only the `Handle` method.
 func NewHandleInlineMiddleware(handleFunc func(ctx context.Context, record slog.Record, next func(context.Context, slog.Record) error) error) Middleware {
 	return func(next slog.Handler) slog.Handler {
+		if next == nil {
+			panic("slog-multi: next is required")
+		}
+		if handleFunc == nil {
+			panic("slog-multi: handleFunc is required")
+		}
+
 		return &HandleInlineMiddleware{
 			next:       next,
 			handleFunc: handleFunc,

middleware_inline_with_attrs.go

@@ -9,6 +9,13 @@ import (
 // NewWithAttrsInlineMiddleware is a shortcut to a middleware that implements only the `WithAttrs` method.
 func NewWithAttrsInlineMiddleware(withAttrsFunc func(attrs []slog.Attr, next func([]slog.Attr) slog.Handler) slog.Handler) Middleware {
 	return func(next slog.Handler) slog.Handler {
+		if withAttrsFunc == nil {
+			panic("slog-multi: withAttrsFunc is required")
+		}
+		if next == nil {
+			panic("slog-multi: next is required")
+		}
+
 		return &WithAttrsInlineMiddleware{
 			next:          next,
 			withAttrsFunc: withAttrsFunc,

middleware_inline_with_group.go

@@ -9,6 +9,13 @@ import (
 // NewWithGroupInlineMiddleware is a shortcut to a middleware that implements only the `WithAttrs` method.
 func NewWithGroupInlineMiddleware(withGroupFunc func(name string, next func(string) slog.Handler) slog.Handler) Middleware {
 	return func(next slog.Handler) slog.Handler {
+		if next == nil {
+			panic("slog-multi: next is required")
+		}
+		if withGroupFunc == nil {
+			panic("slog-multi: withGroupFunc is required")
+		}
+
 		return &WithGroupInlineMiddleware{
 			next:          next,
 			withGroupFunc: withGroupFunc,