Allow a resolver to be injected before the system resolver

This allows, for example, cdi mode to be detected.

Signed-off-by: Evan Lezar <[email protected]>

Author: elezar

pkg/nvlib/info/builder.go

@@ -27,6 +27,7 @@ type builder struct {
 	nvmllib   nvml.Interface
 	devicelib device.Interface
 
+	preHook    Resolver
 	properties Properties
 }
 
@@ -48,6 +49,9 @@ func New(opts ...Option) Interface {
 	if b.devicelib == nil {
 		b.devicelib = device.New(device.WithNvml(b.nvmllib))
 	}
+	if b.preHook == nil {
+		b.preHook = noop{}
+	}
 	if b.properties == nil {
 		b.properties = &info{
 			root:      b.root,
@@ -79,6 +83,7 @@ func (b *builder) getResolvers() Resolver {
 
 	return firstOf([]Resolver{
 		auto,
+		b.preHook,
 		systemMode,
 	})
 }

pkg/nvlib/info/options.go

@@ -52,6 +52,13 @@ func WithRoot(root string) Option {
 	}
 }
 
+// WithPreHookResolver provides an Option to set resolvers to use before others.
+func WithPreHookResolver(preHook Resolver) Option {
+	return func(i *builder) {
+		i.preHook = preHook
+	}
+}
+
 // WithProperties provides an Option to set the Properties interface implementation.
 // This is predominantly used for testing.
 func WithProperties(properties Properties) Option {