Adding internal/file/hasher test cases (#1049)

internal/file/hasher_test.go

@@ -0,0 +1,85 @@
+package file
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/spf13/afero"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestValidateByHash(t *testing.T) {
+	testsCases := []struct {
+		name, path, hashStr, actualHash string
+		setup                           func(fs afero.Fs)
+		valid                           bool
+		err                             bool
+		errMsg                          error
+	}{
+		{
+			name:    "Valid SHA256 hash",
+			path:    "test.txt",
+			hashStr: "sha256:9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08",
+			setup: func(fs afero.Fs) {
+				afero.WriteFile(fs, "test.txt", []byte("test"), 0644)
+			},
+			actualHash: "sha256:9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08",
+			valid:      true,
+			err:        false,
+		},
+		{
+			name:    "Invalid SHA256 hash",
+			path:    "test.txt",
+			hashStr: "sha256:deadbeef",
+			setup: func(fs afero.Fs) {
+				afero.WriteFile(fs, "test.txt", []byte("test"), 0644)
+			},
+			actualHash: "sha256:9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08",
+			valid:      false,
+			err:        false,
+		},
+		{
+			name:    "Unsupported hash function",
+			path:    "test.txt",
+			hashStr: "md5:deadbeef",
+			setup: func(fs afero.Fs) {
+				afero.WriteFile(fs, "test.txt", []byte("test"), 0644)
+			},
+			actualHash: "",
+			valid:      false,
+			err:        true,
+			errMsg:     fmt.Errorf("hasher not supported or specified (given: md5:deadbeef)"),
+		},
+		{
+			name:       "File does not exist",
+			path:       "nonexistent.txt",
+			hashStr:    "sha256:deadbeef",
+			setup:      func(fs afero.Fs) {},
+			valid:      false,
+			actualHash: "",
+			err:        true,
+		},
+	}
+
+	for _, tc := range testsCases {
+		t.Run(tc.name, func(t *testing.T) {
+			fs := afero.NewMemMapFs()
+			tc.setup(fs)
+
+			valid, actualHash, err := ValidateByHash(fs, tc.path, tc.hashStr)
+
+			assert.Equal(t, tc.valid, valid)
+			assert.Equal(t, tc.actualHash, actualHash)
+
+			if tc.err {
+				assert.Error(t, err)
+			} else {
+				assert.NoError(t, err)
+			}
+
+			if tc.errMsg != nil {
+				assert.Equal(t, tc.errMsg, err)
+			}
+		})
+	}
+}