some more tests in grok_test.go

exporter/grok_test.go

@@ -2,6 +2,7 @@ package exporter
 
 import (
 	"testing"
+	"strings"
 )
 
 func TestAllRegexpsCompile(t *testing.T) {
@@ -13,3 +14,31 @@ func TestAllRegexpsCompile(t *testing.T) {
 		}
 	}
 }
+
+func TestUnknownGrokPattern(t *testing.T) {
+	patterns := loadPatternDir(t)
+	_, err := Compile("%{USER} [a-z] %{SOME_UNKNOWN_PATTERN}.*", patterns)
+	if err == nil || ! strings.Contains(err.Error(), "SOME_UNKNOWN_PATTERN") {
+		t.Error("expected error message saying which pattern is undefined.")
+	}
+}
+
+func TestInvalidRegexp(t *testing.T) {
+	patterns := loadPatternDir(t)
+	_, err := Compile("%{USER} [a-z] \\", patterns) // wrong because regex cannot end with backslash
+	if err == nil || ! strings.Contains(err.Error(), "%{USER} [a-z] \\") {
+		t.Error("expected error message saying which pattern is invalid.")
+	}
+}
+
+func TestNamedCaptureGroup(t *testing.T) {
+	patterns := loadPatternDir(t)
+	regex, err := Compile("User %{USER:user} has logged in.", patterns)
+	if err != nil {
+		t.Error(err)
+	}
+	found := regex.Gsub("User fabian has logged in.", "\\k<user>")
+	if found != "fabian" {
+		t.Errorf("Expected to capture 'fabian', but captured '%v'.", found)
+	}
+}