Update function descriptions (#3025)

* Made changes to componenttest package

* Changes to nop_exporter_test

* Reverted the changes in exporter and nop_exporter

* Updated comments for the Factory

* reverted usage of singletons

component/componenttest/nop_extension.go

@@ -31,7 +31,7 @@ type nopExtensionFactory struct{}
 
 var nopExtensionFactoryInstance = &nopExtensionFactory{}
 
-// NewNopExtensionFactory returns a component.ExtensionFactory that constructs nop exporters.
+// NewNopExtensionFactory returns a component.ExtensionFactory that constructs nop extensions.
 func NewNopExtensionFactory() component.ExtensionFactory {
 	return nopExtensionFactoryInstance
 }

component/componenttest/nop_processor.go

@@ -35,7 +35,7 @@ type nopProcessorFactory struct {
 
 var nopProcessorFactoryInstance = &nopProcessorFactory{}
 
-// NewNopProcessorFactory returns a component.ProcessorFactory that constructs nop exporters.
+// NewNopProcessorFactory returns a component.ProcessorFactory that constructs nop processors.
 func NewNopProcessorFactory() component.ProcessorFactory {
 	return nopProcessorFactoryInstance
 }

component/componenttest/nop_receiver.go

@@ -32,7 +32,7 @@ type nopReceiverFactory struct{}
 
 var nopReceiverFactoryInstance = &nopReceiverFactory{}
 
-// NewNopReceiverFactory returns a component.ReceiverFactory that constructs nop exporters.
+// NewNopReceiverFactory returns a component.ReceiverFactory that constructs nop receivers.
 func NewNopReceiverFactory() component.ReceiverFactory {
 	return nopReceiverFactoryInstance
 }

component/exporter_test.go

@@ -48,7 +48,7 @@ func (f *TestExporterFactory) CreateMetricsExporter(context.Context, ExporterCre
 	return nil, componenterror.ErrDataTypeIsNotSupported
 }
 
-// CreateMetricsExporter creates a logs exporter based on this config.
+// CreateLogsExporter creates a logs exporter based on this config.
 func (f *TestExporterFactory) CreateLogsExporter(context.Context, ExporterCreateParams, config.Exporter) (LogsExporter, error) {
 	return nil, componenterror.ErrDataTypeIsNotSupported
 }

component/receiver.go

@@ -65,8 +65,8 @@ type ReceiverCreateParams struct {
 	BuildInfo BuildInfo
 }
 
-// ReceiverFactory can create TracesReceiver and MetricsReceiver. This is the
-// new preferred factory type to create receivers.
+// ReceiverFactory can create TracesReceiver, MetricsReceiver and
+// and LogsReceiver. This is the new preferred factory type to create receivers.
 type ReceiverFactory interface {
 	Factory