add tests for initializing filter regexes

selfupdate/updater_test.go

@@ -2,6 +2,7 @@ package selfupdate
 
 import (
 	"os"
+	"strings"
 	"testing"
 )
 
@@ -67,3 +68,39 @@ func TestGitHubEnterpriseClientInvalidURL(t *testing.T) {
 		t.Fatal("Invalid URL should raise an error")
 	}
 }
+
+func TestCompileRegexForFiltering(t *testing.T) {
+	filters := []string{
+		"^hello$",
+		"^(\\d\\.)+\\d$",
+	}
+	up, err := NewUpdater(Config{
+		Filters: filters,
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(up.filters) != 2 {
+		t.Fatalf("Wanted 2 regexes but got %d", len(up.filters))
+	}
+	for i, r := range up.filters {
+		want := filters[i]
+		got := r.String()
+		if want != got {
+			t.Errorf("Compiled regex is %q but specified was %q", got, want)
+		}
+	}
+}
+
+func TestFilterRegexIsBroken(t *testing.T) {
+	_, err := NewUpdater(Config{
+		Filters: []string{"(foo"},
+	})
+	if err == nil {
+		t.Fatal("Error unexpectedly did not occur")
+	}
+	msg := err.Error()
+	if !strings.Contains(msg, "Could not compile regular expression \"(foo\" for filtering releases") {
+		t.Fatalf("Error message is unexpected: %q", msg)
+	}
+}