add source with func name

source_example_test.go

@@ -0,0 +1,25 @@
+package log_test
+
+import (
+	"context"
+
+	"gitoa.ru/go-4devs/log"
+)
+
+func ExampleWithSource() {
+	ctx := context.Background()
+	logger := log.New(log.WithStdout()).With(log.WithSource(1))
+
+	logger.Debug(ctx, "debug message")
+	// Output:
+	// msg="debug message" source=source_example_test.go:13
+}
+
+func ExampleWithSource_json() {
+	ctx := context.Background()
+	logger := log.New(log.WithStdout(), log.WithJSONFormat()).With(log.WithSource(1))
+
+	logger.Debug(ctx, "debug message")
+	// Output:
+	// {"msg":"debug message","source":{"file":"source_example_test.go","line":22,"func":"log_test.ExampleWithSource_json"}}
+}