history: don't import build package

Signed-off-by: CrazyMax <1951866+crazy-max@users.noreply.github.com>

util/urlutil/urlutil.go

@@ -0,0 +1,25 @@
+package urlutil
+
+import (
+	"strings"
+
+	"github.com/moby/buildkit/frontend/dockerfile/dfgitutil"
+)
+
+// IsHTTPURL returns true if the provided str is an HTTP(S) URL by checking if
+// it has a http:// or https:// scheme. No validation is performed to verify if
+// the URL is well-formed.
+func IsHTTPURL(str string) bool {
+	return strings.HasPrefix(str, "https://") || strings.HasPrefix(str, "http://")
+}
+
+// IsRemoteURL returns true for HTTP(S) URLs and Git references.
+func IsRemoteURL(c string) bool {
+	if IsHTTPURL(c) {
+		return true
+	}
+	if _, ok, _ := dfgitutil.ParseGitRef(c); ok {
+		return true
+	}
+	return false
+}

util/urlutil/urlutil_test.go

@@ -0,0 +1,110 @@
+package urlutil
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestIsHTTPURL(t *testing.T) {
+	tests := []struct {
+		name  string
+		input string
+		want  bool
+	}{
+		{
+			name:  "https url",
+			input: "https://example.com/repo.git",
+			want:  true,
+		},
+		{
+			name:  "http url",
+			input: "http://example.com/repo.git",
+			want:  true,
+		},
+		{
+			name:  "http prefix only",
+			input: "http://",
+			want:  true,
+		},
+		{
+			name:  "non-http protocol",
+			input: "git://example.com/repo.git",
+			want:  false,
+		},
+		{
+			name:  "no protocol",
+			input: "example.com/repo.git",
+			want:  false,
+		},
+		{
+			name:  "uppercase protocol is not matched",
+			input: "HTTPS://example.com/repo.git",
+			want:  false,
+		},
+		{
+			name:  "leading whitespace does not match",
+			input: " https://example.com/repo.git",
+			want:  false,
+		},
+	}
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			require.Equal(t, tc.want, IsHTTPURL(tc.input))
+		})
+	}
+}
+
+func TestIsRemoteURL(t *testing.T) {
+	tests := []struct {
+		name  string
+		input string
+		want  bool
+	}{
+		{
+			name:  "https url is remote",
+			input: "https://example.com/not-a-git-url",
+			want:  true,
+		},
+		{
+			name:  "http url is remote",
+			input: "http://example.com/path",
+			want:  true,
+		},
+		{
+			name:  "scp style git remote",
+			input: "git@github.com:moby/buildkit.git",
+			want:  true,
+		},
+		{
+			name:  "github shorthand git remote",
+			input: "github.com/moby/buildkit",
+			want:  true,
+		},
+		{
+			name:  "relative local path is not remote",
+			input: "./hack",
+			want:  false,
+		},
+		{
+			name:  "plain local path is not remote",
+			input: "hack/dockerfiles",
+			want:  false,
+		},
+		{
+			name:  "unknown protocol is not remote",
+			input: "docker-image://alpine",
+			want:  false,
+		},
+		{
+			name:  "empty is not remote",
+			input: "",
+			want:  false,
+		},
+	}
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			require.Equal(t, tc.want, IsRemoteURL(tc.input))
+		})
+	}
+}