From f20984e6f08489a697988bf6c1cd93556cab46f6 Mon Sep 17 00:00:00 2001
From: Alex Yatskov <alex@foosoft.net>
Date: Sun, 21 Aug 2016 12:54:44 -0700
Subject: [PATCH] Improved error logging

---
 context.go   |  8 ++++----
 core.go      |  4 ++--
 goldsmith.go | 15 ++++++++++++---
 loader.go    |  4 ++++
 4 files changed, 22 insertions(+), 9 deletions(-)

diff --git a/context.go b/context.go
index a29e9c9..7b33e4c 100644
--- a/context.go
+++ b/context.go
@@ -45,7 +45,7 @@ func (ctx *context) chain() {
 		var err error
 		filters, err = initializer.Initialize(ctx)
 		if err != nil {
-			ctx.gs.fault(nil, err)
+			ctx.gs.fault(ctx.plug.Name(), nil, err)
 			return
 		}
 	}
@@ -77,10 +77,10 @@ func (ctx *context) chain() {
 
 					if accept {
 						if _, err := f.Seek(0, os.SEEK_SET); err != nil {
-							ctx.gs.fault(f, err)
+							ctx.gs.fault("core", f, err)
 						}
 						if err := processor.Process(ctx, f); err != nil {
-							ctx.gs.fault(f, err)
+							ctx.gs.fault(ctx.plug.Name(), f, err)
 						}
 					} else {
 						ctx.output <- f
@@ -93,7 +93,7 @@ func (ctx *context) chain() {
 
 	if finalizer, ok := ctx.plug.(Finalizer); ok {
 		if err := finalizer.Finalize(ctx); err != nil {
-			ctx.gs.fault(nil, err)
+			ctx.gs.fault(ctx.plug.Name(), nil, err)
 		}
 	}
 }
diff --git a/core.go b/core.go
index 4a47e5d..8421c37 100644
--- a/core.go
+++ b/core.go
@@ -85,11 +85,11 @@ func (gs *goldsmith) exportFile(f *file) error {
 	return nil
 }
 
-func (gs *goldsmith) fault(f *file, err error) {
+func (gs *goldsmith) fault(name string, f *file, err error) {
 	gs.errorMtx.Lock()
 	defer gs.errorMtx.Unlock()
 
-	ferr := &Error{Err: err}
+	ferr := &Error{Name: name, Err: err}
 	if f != nil {
 		ferr.Path = f.path
 	}
diff --git a/goldsmith.go b/goldsmith.go
index b61b865..407cc7a 100644
--- a/goldsmith.go
+++ b/goldsmith.go
@@ -25,6 +25,7 @@ package goldsmith
 import (
 	"bytes"
 	"errors"
+	"fmt"
 	"io"
 	"os"
 	"time"
@@ -97,12 +98,18 @@ type Context interface {
 }
 
 type Error struct {
-	Err  error
+	Name string
 	Path string
+	Err  error
 }
 
 func (e Error) Error() string {
-	return e.Err.Error()
+	var path string
+	if len(e.Path) > 0 {
+		path = "@" + e.Path
+	}
+
+	return fmt.Sprintf("[%s%s]: %s", e.Name, path, e.Err.Error())
 }
 
 type Initializer interface {
@@ -117,4 +124,6 @@ type Finalizer interface {
 	Finalize(ctx Context) error
 }
 
-type Plugin interface{}
+type Plugin interface {
+	Name() string
+}
diff --git a/loader.go b/loader.go
index 9aae5ac..f077e03 100644
--- a/loader.go
+++ b/loader.go
@@ -26,6 +26,10 @@ import "path/filepath"
 
 type loader struct{}
 
+func (*loader) Name() string {
+	return "loader"
+}
+
 func (*loader) Initialize(ctx Context) ([]string, error) {
 	infos := make(chan fileInfo)
 	go scanDir(ctx.SrcDir(), infos)