Implement PDF comparison with rudimentary byte-difference display. If a reference file exists, it will be compared with its associated example file. If the reference file is missing, the associated example file is considered to be without differences. PDF files in any subdirectory named reference are not deleted when the test begins. This commit is broken -- it illustrates how the use of maps for fonts, images and other resources lead to different dictionary tables in the PDF document.

1 files changed, 23 insertions, 29 deletions

diff --git a/internal/example/example.go b/internal/example/example.go
index 9e2c736..b95972c 100644
--- a/internal/example/example.go
+++ b/internal/example/example.go
@@ -18,13 +18,14 @@
 package example
 
 import (
-	"bytes"
 	"fmt"
-	"io/ioutil"
+	//	"io/ioutil"
 	"os"
 	"path/filepath"
 	"regexp"
 	"strings"
+
+	"github.com/jung-kurt/gofpdf"
 )
 
 var gofpdfDir string
@@ -39,8 +40,7 @@ func setRoot() {
 	wdStr, err := os.Getwd()
 	if err == nil {
 		gofpdfDir = ""
-		sepStr := string(os.PathSeparator)
-		list := strings.Split(wdStr, sepStr)
+		list := strings.Split(filepath.ToSlash(wdStr), "/")
 		for j := len(list) - 1; j >= 0 && list[j] != "gofpdf"; j-- {
 			gofpdfDir = filepath.Join(gofpdfDir, "..")
 		}
@@ -103,38 +103,32 @@ var (
 // compared except for the value of the /CreationDate field in the PDF. An
 // error is returned if the two files do not match. If the reference file does
 // not exist, a copy of the specified file is made and a non-nil error is
-// returned only if this copy fails.
+// returned only if this copy fails. If the reference file exists but has zero
+// length, the file will not be overwritten and will be considered to be equal
+// to the example file. This is intended to facilitate initial example
+// development.
 func referenceCompare(fileStr string) (err error) {
-	var fileBuf, refFileBuf []byte
 	var refFileStr, refDirStr, dirStr, baseFileStr string
+	// var fileBuf []byte
+	// var info os.FileInfo
 	dirStr, baseFileStr = filepath.Split(fileStr)
 	refDirStr = filepath.Join(dirStr, "reference")
 	err = os.MkdirAll(refDirStr, 0755)
 	if err == nil {
 		refFileStr = filepath.Join(refDirStr, baseFileStr)
-		fileBuf, err = ioutil.ReadFile(fileStr)
-		if err == nil {
-			// Replace the creation timestamp of this PDF with a fixed value
-			fileBuf = creationDateRe.ReplaceAll(fileBuf, fixDate)
-			refFileBuf, err = ioutil.ReadFile(refFileStr)
-			if err == nil {
-				if len(fileBuf) == len(refFileBuf) {
-					if bytes.Equal(fileBuf, refFileBuf) {
-						// Files match
-					} else {
-						err = fmt.Errorf("%s differs from %s", fileStr, refFileStr)
-					}
-				} else {
-					err = fmt.Errorf("size of %s (%d) does not match size of %s (%d)",
-						fileStr, len(fileBuf), refFileStr, len(refFileBuf))
-				}
-			} else {
-				// Reference file is missing. Create it with a copy of the newly produced
-				// file in which the creation date has been fixed. Overwrite error with copy
-				// error.
-				err = ioutil.WriteFile(refFileStr, fileBuf, 0644)
-			}
-		}
+		// info, err = os.Stat(refFileStr)
+		// if err == nil {
+		//	if info.Size() > 0 {
+		err = gofpdf.ComparePDFFiles(fileStr, refFileStr)
+		//	}
+		// 		} else {
+		// 			// Reference file is missing. Create it with a copy of the example file.
+		// 			// Overwrite error with copy error.
+		// 			fileBuf, err = ioutil.ReadFile(fileStr)
+		// 			if err == nil {
+		// 				err = ioutil.WriteFile(refFileStr, fileBuf, 0644)
+		// 			}
+		// 		}
 	}
 	return
 }