Moving from codeowners.New to codeowners.NewDecoder (#4)

Author: fmenezes

codeowners.go

@@ -13,30 +13,33 @@ var DefaultLocations = [...]string{"CODEOWNERS", "docs/CODEOWNERS", ".github/COD
 // Decoder providers functionality to read CODEOWNERS data
 type Decoder struct {
 	scanner *bufio.Scanner
-	line    *string
+	line    string
 	done    bool
 }
 
-// New generates a new CodeOwnersScanner instance. The reader should be a reader containing the contents of the CODEOWNERS file
-func New(r io.Reader) *Decoder {
+// NewDecoder generates a new CodeOwnersScanner instance. The reader should be a reader containing the contents of the CODEOWNERS file
+func NewDecoder(r io.Reader) *Decoder {
 	return &Decoder{
 		scanner: bufio.NewScanner(r),
-		line:    nil,
+		line:    "",
 		done:    false,
 	}
 }
 
+// peek will scan the next line
 func (s *Decoder) peek() {
 	if !s.scanner.Scan() {
 		s.done = true
+		return
 	}
 	line := sanitiseLine(s.scanner.Text())
-	s.line = &line
-	if len(*s.line) == 0 && !s.done {
+	s.line = line
+	if len(s.line) == 0 && !s.done {
 		s.peek()
 	}
 }
 
+// sanitiseLine removes all empty space and comments from a given line
 func sanitiseLine(line string) string {
 	i := strings.Index(line, "#")
 	if i >= 0 {
@@ -45,15 +48,18 @@ func sanitiseLine(line string) string {
 	return strings.Trim(line, " ")
 }
 
-// More returns if there are available CODEOWNERS lines to be scanned
+// More returns true if there are available CODEOWNERS lines to be scanned.
+// And also advances to the next line.
 func (s *Decoder) More() bool {
 	s.peek()
 	return !s.done
 }
 
-// Token parses the next available line in the CODEOWNERS file
+// Token parses the next available line in the CODEOWNERS file.
+// If More was never called it will return an empty token.
+// After end of file Token will always return the last line.
 func (s *Decoder) Token() Token {
-	line := strings.ReplaceAll(*s.line, "\\ ", "\\s")
+	line := strings.ReplaceAll(s.line, "\\ ", "\\s")
 
 	data := strings.Split(line, " ")
 

codeowners_test.go

@@ -9,12 +9,12 @@ import (
 )
 
 func exec(input string) ([][]string, int) {
-	scanner := codeowners.New(strings.NewReader(input))
+	decoder := codeowners.NewDecoder(strings.NewReader(input))
 	got := [][]string{}
 	c := 0
-	for scanner.More() {
+	for decoder.More() {
 		c++
-		token := scanner.Token()
+		token := decoder.Token()
 		got = append(got, append([]string{token.Path()}, token.Owners()...))
 	}
 	return got, c
@@ -90,3 +90,34 @@ func TestNoOwners(t *testing.T) {
 		{"*"},
 	})
 }
+
+func TestLastToken(t *testing.T) {
+	decoder := codeowners.NewDecoder(strings.NewReader(`filepattern @owner`))
+	if !decoder.More() {
+		t.Error("More should be true")
+	}
+	for i := 0; i < 3; i++ { //calling 3 times to prove it always returns the last line
+		token := decoder.Token()
+		if token.Path() != "filepattern" {
+			t.Error("Path should be 'filepattern'")
+		}
+		if len(token.Owners()) != 1 || token.Owners()[0] != "@owner" {
+			t.Error("Owners should match ['@owner']")
+		}
+
+		if decoder.More() {
+			t.Error("More should be false")
+		}
+	}
+}
+
+func TestMoreNotCalled(t *testing.T) {
+	decoder := codeowners.NewDecoder(strings.NewReader(`filepattern @owner`))
+	token := decoder.Token()
+	if token.Path() != "" {
+		t.Error("Path should be empty")
+	}
+	if len(token.Owners()) != 0 {
+		t.Error("Owners should be empty")
+	}
+}

example_codeowners_test.go

@@ -8,7 +8,7 @@ import (
 )
 
 func Example() {
-	codeownerDecoder := codeowners.New(strings.NewReader(`* test@example.org`))
+	codeownerDecoder := codeowners.NewDecoder(strings.NewReader(`* test@example.org`))
 	for codeownerDecoder.More() {
 		token := codeownerDecoder.Token()
 		fmt.Printf("File Pattern: %s\n", token.Path())