support checksum files without filename inside

checksum/checksum.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"io"
 	"os"
+	"path/filepath"
 	"strings"
 )
 
@@ -48,25 +49,45 @@ func Parse(checksumFile string) ([]Pair, error) {
 	}
 
 	cs := parseChecksumLines(b)
+	if len(cs) == 0 {
+		return checksums, fmt.Errorf("no checksums in %s", checksumFile)
+	}
+	for i := range cs {
+		// Since there is no filename field in the checksumFile get the
+		// filename from the checksumFile name.
+		if cs[i].Filename == "" {
+			cs[i].Filename = trimSuffix(checksumFile)
+		}
+	}
 	checksums = append(checksums, cs...)
 
 	return checksums, nil
 }
 
+// trimSuffix removes suffix (like .sha256) from the filename.
+func trimSuffix(filename string) string {
+	suffix := filepath.Ext(filename)
+	return strings.TrimSuffix(filename, suffix)
+}
+
 // parseChecksumLines parses bytes from a checksums file. The bytes look like:
 // 712f37d14687e10ae0425bf7e5d0faf17c49f9476b8bb6a96f2a3f91b0436db2  checkip_0.45.1_linux_armv6.tar.gz
 // ba47c83b6038dda089dd1410b9e97d1de7e4adea7620c856f9b74a782048e272  checkip_0.45.1_linux_amd64.tar.gz
 func parseChecksumLines(b []byte) []Pair {
 	var checksums []Pair
 	for _, line := range strings.Split(string(b), "\n") {
 		fields := strings.Fields(line)
-		if len(fields) != 2 {
-			continue
+		switch len(fields) {
+		case 2:
+			checksums = append(checksums, Pair{
+				Checksum: fields[0],
+				Filename: fields[1],
+			})
+		case 1:
+			checksums = append(checksums, Pair{
+				Checksum: fields[0],
+			})
 		}
-		checksums = append(checksums, Pair{
-			Checksum: fields[0],
-			Filename: fields[1],
-		})
 	}
 	return checksums
 }

checksum/checksum_test.go

@@ -1,39 +1,61 @@
 package checksum
 
 import (
-	"io"
-	"os"
 	"testing"
 )
 
-var test = struct {
-	fileName      string
-	fileChecksum  string // calculated using sha256sum
-	checksumsFile string // contains checksum of file and file name
+var tests = []struct {
+	fileName     string
+	fileChecksum string // calculated using sha256sum
+	checksumFile string // contains checksum of file and optionally file name
 }{
-	fileName:      "testdata/file-to-checksum",
-	fileChecksum:  "b94d27b9934d3e08a52e52d7da7dabfac484efe37a5380ee9088f7ace2efcde9",
-	checksumsFile: "testdata/checksum-file", // only one line here
+	{
+		fileName:     "testdata/file-to-checksum",
+		fileChecksum: "b94d27b9934d3e08a52e52d7da7dabfac484efe37a5380ee9088f7ace2efcde9",
+		checksumFile: "testdata/checksum-file",
+	},
+	{
+		fileName:     "testdata/file-to-checksum",
+		fileChecksum: "b94d27b9934d3e08a52e52d7da7dabfac484efe37a5380ee9088f7ace2efcde9",
+		checksumFile: "testdata/file-to-checksum.sha256",
+	},
 }
 
-func TestParseChecksumsLines(t *testing.T) {
-	file, err := os.Open(test.checksumsFile)
-	if err != nil {
-		t.Error(err)
-	}
-	defer file.Close()
+func TestParse(t *testing.T) {
+	for _, test := range tests {
+		checksums, err := Parse(test.checksumFile)
+		if err != nil {
+			t.Error(err)
+		}
+
+		for _, c := range checksums {
+			got := c.Checksum
+			want := test.fileChecksum
+			if got != want {
+				t.Errorf("wrong checksum: got %q, want %q", got, want)
+			}
 
-	b, err := io.ReadAll(file)
-	if err != nil {
-		t.Error(err)
+			got = c.Filename
+			want = test.fileName
+			if got != want {
+				t.Errorf("wrong filename: got %q, want %q", got, want)
+			}
+		}
 	}
+}
 
-	cs := parseChecksumLines(b)
-	for _, c := range cs {
-		got := c.Checksum
-		want := test.fileChecksum
-		if got != want {
-			t.Errorf("wrong checksum: got %s, want %s", got, want)
+func TestTrimSuffix(t *testing.T) {
+	tests := []struct {
+		filename string
+		want     string
+	}{
+		{"", ""},
+		{"starship-aarch64-apple-darwin.tar.gz.sha256", "starship-aarch64-apple-darwin.tar.gz"},
+	}
+	for _, test := range tests {
+		got := trimSuffix(test.filename)
+		if got != test.want {
+			t.Errorf("trimSuffix(%s) = %s, want %s", test.filename, got, test.want)
 		}
 	}
 }

checksum/testdata/file-to-checksum.sha256

@@ -0,0 +1 @@
+b94d27b9934d3e08a52e52d7da7dabfac484efe37a5380ee9088f7ace2efcde9