test: syslog extract message

Author: mlataza

internal/syslog/common.go internal/syslog/syslog.gointernal/syslog/common.go renamed to internal/syslog/syslog.go

@@ -0,0 +1,51 @@
+package syslog
+
+import "testing"
+
+func TestExtractMessage(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    string
+		expected string
+	}{
+		{
+			name:     "info prefix",
+			input:    "[INFO] some message",
+			expected: "some message",
+		},
+		{
+			name:     "debug prefix",
+			input:    "[DEBUG] debug output",
+			expected: "debug output",
+		},
+		{
+			name:     "warn prefix",
+			input:    "[WARN] something went wrong",
+			expected: "something went wrong",
+		},
+		{
+			name:     "error prefix",
+			input:    "[ERROR] fatal error occurred",
+			expected: "fatal error occurred",
+		},
+		{
+			name:     "message with brackets in content",
+			input:    "[INFO] result [ok]",
+			expected: "result [ok]",
+		},
+		{
+			name:     "no bracket in line",
+			input:    "xno bracket here",
+			expected: "no bracket here",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := extractMessage(tt.input)
+			if got != tt.expected {
+				t.Errorf("extractMessage(%q) = %q, want %q", tt.input, got, tt.expected)
+			}
+		})
+	}
+}