Add tests for helpers

sign/helpers.go

@@ -1,14 +1,14 @@
 package sign
 
 import (
-	"bitbucket.org/digitorus/pdf"
 	"errors"
 	"fmt"
 	"io"
 	"math"
-	"os"
 	"strings"
 	"time"
+
+	"bitbucket.org/digitorus/pdf"
 )
 
 func findFirstPage(parent pdf.Value) (pdf.Value, error) {
@@ -73,10 +73,13 @@ func pdfDateTime(date time.Time) string {
 }
 
 func leftPad(s string, padStr string, pLen int) string {
+	if pLen <= 0 {
+		return s
+	}
 	return strings.Repeat(padStr, pLen) + s
 }
 
-func writePartFromSourceFileToTargetFile(input_file *os.File, output_file *os.File, offset int64, length int64) error {
+func writePartFromSourceFileToTargetFile(input_file io.ReadSeeker, output_file io.Writer, offset int64, length int64) error {
 	input_file.Seek(offset, 0)
 
 	// Create a small buffer for proper IO handling.

sign/helpers_test.go

@@ -0,0 +1,183 @@
+package sign
+
+import (
+	"bufio"
+	"bytes"
+	"os"
+	"testing"
+	"time"
+
+	"bitbucket.org/digitorus/pdf"
+)
+
+func TestFindFirstPage(t *testing.T) {
+	input_file, reader := loadHelpersTestPDF()
+	if input_file == nil || reader == nil {
+		t.Errorf("Failed to load test PDF")
+		return
+	}
+
+	root := reader.Trailer().Key("Root")
+	root_keys := root.Keys()
+	found_pages := false
+	for _, key := range root_keys {
+		if key == "Pages" {
+			found_pages = true
+			break
+		}
+	}
+
+	if !found_pages {
+		input_file.Close()
+		t.Errorf("Could not find pages element")
+		return
+	}
+
+	first_page, err := findFirstPage(root.Key("Pages"))
+	if err != nil {
+		input_file.Close()
+		t.Errorf("Could not find first page")
+		return
+	}
+
+	first_page_ptr := first_page.GetPtr()
+	if first_page_ptr.GetGen() != 0 {
+		input_file.Close()
+		t.Errorf("First page gen mismatch")
+	}
+
+	if first_page_ptr.GetID() != 4 {
+		t.Errorf("First page ID mismatch")
+	}
+
+	input_file.Close()
+}
+
+func TestPDFString(t *testing.T) {
+	string_compare := map[string]string{
+		"Test":    "(Test)",
+		"((Test)": "(\\(\\(Test\\))",
+		"\\TEst":  "(\\\\TEst)",
+		"\rnew":   "(\\rnew)",
+	}
+
+	for text, expected := range string_compare {
+		if pdfString(text) != expected {
+			t.Errorf("Error while escaping %s. Expected %s, got %s.", text, expected, pdfString(text))
+		}
+	}
+}
+
+func TestPdfDateTime(t *testing.T) {
+	timezone, _ := time.LoadLocation("Europe/Tallinn")
+	timezone_1, _ := time.LoadLocation("Africa/Casablanca")
+	timezone_2, _ := time.LoadLocation("America/New_York")
+	timezone_3, _ := time.LoadLocation("Asia/Jerusalem")
+	timezone_4, _ := time.LoadLocation("Europe/Amsterdam")
+	timezone_5, _ := time.LoadLocation("Pacific/Honolulu")
+
+	now := time.Date(2017, 9, 23, 14, 39, 0, 0, timezone)
+
+	date_compare := map[time.Time]string{
+		now.In(timezone_1): "(D:20170923123900+01'00')",
+		now.In(timezone_2): "(D:20170923073900-04'00')",
+		now.In(timezone_3): "(D:20170923143900+03'00')",
+		now.In(timezone_4): "(D:20170923133900+02'00')",
+		now.In(timezone_5): "(D:20170923013900-10'00')",
+	}
+
+	for date, expected := range date_compare {
+		if pdfDateTime(date) != expected {
+			t.Errorf("Error while converting date %s to string. Expected %s, got %s.", date.String(), expected, pdfDateTime(date))
+		}
+	}
+}
+
+func TestLeftPad(t *testing.T) {
+	string_compare := map[string]string{
+		"123456789": "123456789",
+		"12345678":  "12345678",
+		"1234567":   "_1234567",
+		"123456":    "__123456",
+		"12345":     "___12345",
+		"1234":      "____1234",
+		"123":       "_____123",
+		"12":        "______12",
+		"1":         "_______1",
+		"":          "________",
+	}
+
+	for text, expected := range string_compare {
+		if leftPad(text, "_", 8-len(text)) != expected {
+			t.Errorf("Error while left padding %s. Expected %s, got %s.", text, expected, leftPad(text, "_", 8-len(text)))
+		}
+	}
+}
+
+func TestWritePartFromSourceFileToTargetFile(t *testing.T) {
+	var b bytes.Buffer
+	writer := bufio.NewWriter(&b)
+
+	input_file, err := os.Open("../testfiles/benchmark.pdf")
+	if err != nil {
+		t.Errorf("Failed to load test PDF")
+		return
+	}
+
+	writePartFromSourceFileToTargetFile(input_file, writer, 0, 0)
+	writer.Flush()
+
+	if writer.Buffered() != 0 {
+		t.Errorf("Content was copied while length was 0")
+	}
+
+	writePartFromSourceFileToTargetFile(input_file, writer, 0, -20)
+	writer.Flush()
+
+	if writer.Buffered() != 0 {
+		t.Errorf("Content was copied while length was smaller than 0")
+	}
+
+	writePartFromSourceFileToTargetFile(input_file, writer, 0, 8)
+	writer.Flush()
+
+	if string(b.Bytes()) != "%PDF-2.0" {
+		t.Errorf("Wrong content was copied, got %s but expected %s", string(b.Bytes()), "%PDF-2.0")
+	}
+
+	writePartFromSourceFileToTargetFile(input_file, writer, 33, 8)
+	writer.Flush()
+
+	if string(b.Bytes()) != "%PDF-2.0/Catalog" {
+		t.Errorf("Wrong content was copied, got %s but expected %s", string(b.Bytes()), "%PDF-2.0/Catalog")
+	}
+
+	writePartFromSourceFileToTargetFile(input_file, writer, 0, 1200)
+
+	if writer.Buffered() != 1200 {
+		t.Errorf("Requested 1200 bytes but only got %d", writer.Buffered())
+	}
+
+	input_file.Close()
+}
+
+func loadHelpersTestPDF() (*os.File, *pdf.Reader) {
+	input_file, err := os.Open("../testfiles/benchmark.pdf")
+	if err != nil {
+		return nil, nil
+	}
+
+	finfo, err := input_file.Stat()
+	if err != nil {
+		input_file.Close()
+		return nil, nil
+	}
+	size := finfo.Size()
+
+	rdr, err := pdf.NewReader(input_file, size)
+	if err != nil {
+		return nil, nil
+	}
+
+	return input_file, rdr
+}