test: test scanner

go.mod

@@ -1,5 +1,10 @@
 module github.com/LGBT-CN/signature-counter
 
-// use slices.Insert and log/slog module in Go 1.21
-// use slog.SetLogLoggerLevel in Go 1.22
 go 1.21
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/stretchr/testify v1.9.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)

go.sum

@@ -1,2 +1,11 @@
 github.com/KevinZonda/GoX v0.0.15 h1:u+G41/srg8c6bmI6Oqw9iBwYiSQk9FKp9fv/YBZadFk=
 github.com/KevinZonda/GoX v0.0.15/go.mod h1:WHV3YUyG+ou3wuUgwO4SRhMiKxLTVK5inajmtR1MUXo=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/testify v1.9.0 h1:HtqpIVDClZ4nwg75+f6Lvsy/wHu+3BoSGCbBAcpTsTg=
+github.com/stretchr/testify v1.9.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

main.go

@@ -7,21 +7,11 @@ package main
 
 import (
 	"bufio"
-	"fmt"
 	"log"
-	"log/slog"
 	"os"
-	"slices"
 	"strings"
 )
 
-const (
-	SIGNATURE_START = "<!-- BEGIN LGBT-CN SIGNATURE -->"
-	SIGNATURE_END   = "<!-- END LGBT-CN SIGNATURE -->"
-	COUNT_START     = "<!-- BEGIN LGBT-CN COUNT -->"
-	COUNT_END       = "<!-- END LGBT-CN COUNT -->"
-)
-
 func main() {
 	// slog.SetLogLoggerLevel(slog.LevelDebug)
 	if len(os.Args) < 2 {
@@ -35,81 +25,10 @@ func main() {
 	defer file.Close()
 
 	scanner := bufio.NewScanner(file)
-	inSignatureBlock := false
-	inCountBlock := false
-	lineCount := 0
-	lineNumber := 0
-	countStartLine := 0
-	var lines []string
-	for scanner.Scan() {
-		line := scanner.Text()
-		line = strings.TrimSpace(line)
-		slog.Debug(fmt.Sprintf("Parsing line: %d %s", lineNumber, line))
-
-		if line == COUNT_START {
-			slog.Debug("Found count block start")
-			if inSignatureBlock {
-				log.Fatal("Please put count block start outside signature block")
-			}
-			countStartLine = lineNumber
-			inCountBlock = true
-			goto exit
-		}
-		if line == COUNT_END {
-			slog.Debug("Found count block end")
-			if !inCountBlock {
-				log.Fatal("Please put count block start first")
-			}
-			inCountBlock = false
-			goto exit
-		}
-		if line == SIGNATURE_START {
-			slog.Debug("Found signature block start")
-			if inCountBlock {
-				log.Fatal("Please put signature block end outside count block")
-			}
-			inSignatureBlock = true
-			goto exit
-		}
-		if line == SIGNATURE_END {
-			slog.Debug("Found signature block end")
-			if !inSignatureBlock {
-				log.Fatal("Please put signature block start first")
-			}
-			inSignatureBlock = false
-			goto exit
-		}
-		if inSignatureBlock && line != "" {
-			lineCount++
-		}
-		// skip content in count block
-		if inCountBlock {
-			continue
-		}
-	exit:
-		lines = append(lines, line)
-		lineNumber++
-	}
-
-	if err := scanner.Err(); err != nil {
+	lines, err := scan(scanner)
+	if err != nil {
 		log.Fatal(err)
 	}
-
-	if inCountBlock {
-		fmt.Println("Please put count block end")
-	}
-	if inSignatureBlock {
-		fmt.Println("Please put signature block end")
-	}
-
-	slog.Debug(fmt.Sprintf("%d lines in signature block", lineCount))
-	slog.Debug(fmt.Sprintf("count block start at line %d", countStartLine))
-	lines = slices.Insert(lines, countStartLine+1, fmt.Sprintf("已有%d人签署！", lineCount))
-
-	for _, line := range lines {
-		fmt.Println(line)
-	}
-
 	output := strings.Join(lines, "\n")
 
 	err = os.WriteFile(fileName, []byte(output), 644)

scanner.go

@@ -0,0 +1,96 @@
+package main
+
+import (
+	"bufio"
+	"errors"
+	"fmt"
+	"log"
+	"slices"
+	"strings"
+)
+
+const (
+	SIGNATURE_START = "<!-- BEGIN LGBT-CN SIGNATURE -->"
+	SIGNATURE_END   = "<!-- END LGBT-CN SIGNATURE -->"
+	COUNT_START     = "<!-- BEGIN LGBT-CN COUNT -->"
+	COUNT_END       = "<!-- END LGBT-CN COUNT -->"
+)
+
+func scan(scanner *bufio.Scanner) ([]string, error) {
+	inSignatureBlock := false
+	inCountBlock := false
+	lineCount := 0
+	lineNumber := 0
+	// count block does not exists if count equal to zero
+	countStartLine := 0
+	var lines []string
+	for scanner.Scan() {
+		line := scanner.Text()
+		line = strings.TrimSpace(line)
+
+		if line == COUNT_START {
+			if inCountBlock {
+				return nil, errors.New("Please don't use nested count block")
+			}
+			if inSignatureBlock {
+				return nil, errors.New("Please put count block start outside signature block")
+			}
+			// insert count in next line
+			countStartLine = lineNumber + 1
+			inCountBlock = true
+			goto exit
+		}
+		if line == COUNT_END {
+			if !inCountBlock {
+				return nil, errors.New("Please put count block start first")
+			}
+			inCountBlock = false
+			goto exit
+		}
+		if line == SIGNATURE_START {
+			if inSignatureBlock {
+				return nil, errors.New("Please don't use nested signature block")
+			}
+			if inCountBlock {
+				return nil, errors.New("Please put signature block end outside count block")
+			}
+			inSignatureBlock = true
+			goto exit
+		}
+		if line == SIGNATURE_END {
+			if !inSignatureBlock {
+				return nil, errors.New("Please put signature block start first")
+			}
+			inSignatureBlock = false
+			goto exit
+		}
+		if inSignatureBlock && line != "" {
+			lineCount++
+		}
+		// skip content in count block
+		if inCountBlock {
+			continue
+		}
+	exit:
+		lines = append(lines, line)
+		lineNumber++
+	}
+
+	if err := scanner.Err(); err != nil {
+		log.Fatal(err)
+	}
+
+	if inCountBlock {
+		return nil, errors.New("Please put count block end")
+	}
+	if inSignatureBlock {
+		return nil, errors.New("Please put signature block end")
+	}
+
+	if countStartLine == 0 {
+		return nil, errors.New("Please put count block")
+	}
+	lines = slices.Insert(lines, countStartLine, fmt.Sprintf("已有%d人签署！", lineCount))
+
+	return lines, nil
+}

scanner_test.go

@@ -0,0 +1,99 @@
+package main
+
+import (
+	"bufio"
+	"github.com/stretchr/testify/assert"
+	"strings"
+	"testing"
+)
+
+func TestMissCountStart(t *testing.T) {
+	code := `<!-- END LGBT-CN COUNT -->`
+	scanner := bufio.NewScanner(strings.NewReader(code))
+	_, err := scan(scanner)
+	assert.EqualError(t, err, "Please put count block start first")
+}
+
+func TestMissCountEnd(t *testing.T) {
+	code := `<!-- BEGIN LGBT-CN COUNT -->`
+	scanner := bufio.NewScanner(strings.NewReader(code))
+	_, err := scan(scanner)
+	assert.EqualError(t, err, "Please put count block end")
+}
+
+func TestDuplicateCountStart(t *testing.T) {
+	code := `<!-- BEGIN LGBT-CN COUNT -->
+<!-- BEGIN LGBT-CN COUNT -->`
+	scanner := bufio.NewScanner(strings.NewReader(code))
+	_, err := scan(scanner)
+	assert.EqualError(t, err, "Please don't use nested count block")
+}
+
+func TestMissSignatureStart(t *testing.T) {
+	code := `<!-- END LGBT-CN SIGNATURE -->`
+	scanner := bufio.NewScanner(strings.NewReader(code))
+	_, err := scan(scanner)
+	assert.EqualError(t, err, "Please put signature block start first")
+}
+
+func TestMissSignatureEnd(t *testing.T) {
+	code := `<!-- BEGIN LGBT-CN SIGNATURE -->`
+	scanner := bufio.NewScanner(strings.NewReader(code))
+	_, err := scan(scanner)
+	assert.EqualError(t, err, "Please put signature block end")
+}
+
+func TestDuplicateSignatureStart(t *testing.T) {
+	code := `<!-- BEGIN LGBT-CN SIGNATURE -->
+<!-- BEGIN LGBT-CN SIGNATURE -->`
+	scanner := bufio.NewScanner(strings.NewReader(code))
+	_, err := scan(scanner)
+	assert.EqualError(t, err, "Please don't use nested signature block")
+}
+
+func TestMissCount(t *testing.T) {
+	code := `<!-- BEGIN LGBT-CN SIGNATURE -->
+<!-- END LGBT-CN SIGNATURE -->`
+	scanner := bufio.NewScanner(strings.NewReader(code))
+	_, err := scan(scanner)
+	assert.EqualError(t, err, "Please put count block")
+}
+
+// Count should be zero when signature block not exists.
+func TestMissSignature(t *testing.T) {
+	code := `<!-- BEGIN LGBT-CN COUNT -->
+<!-- END LGBT-CN COUNT -->`
+	scanner := bufio.NewScanner(strings.NewReader(code))
+	lines, err := scan(scanner)	
+	assert.Nil(t, err)
+	assert.Equal(t, lines, []string{
+		"<!-- BEGIN LGBT-CN COUNT -->",
+		"已有0人签署！",
+		"<!-- END LGBT-CN COUNT -->",
+	})
+}
+
+func TestSkipEmptyInSignature(t *testing.T) {
+	code := `<!-- BEGIN LGBT-CN COUNT -->
+<!-- END LGBT-CN COUNT -->
+
+<!-- BEGIN LGBT-CN SIGNATURE -->
+unrivaled scalded
+
+reputable overripe
+<!-- END LGBT-CN SIGNATURE -->`
+	scanner := bufio.NewScanner(strings.NewReader(code))
+	lines, err := scan(scanner)
+	assert.Nil(t, err)
+	assert.Equal(t, lines, []string{
+		"<!-- BEGIN LGBT-CN COUNT -->",
+		"已有2人签署！",
+		"<!-- END LGBT-CN COUNT -->",
+		"",
+		"<!-- BEGIN LGBT-CN SIGNATURE -->",
+		"unrivaled scalded",
+		"",
+		"reputable overripe",
+		"<!-- END LGBT-CN SIGNATURE -->",
+	})
+}