test: add unit tests for system package

internal/system/container_test.go

@@ -0,0 +1,152 @@
+package system
+
+import (
+	"testing"
+)
+
+func TestIsHexString(t *testing.T) {
+	tests := []struct {
+		input    string
+		expected bool
+	}{
+		{"0123456789abcdef", true},
+		{"ABCDEF", true},
+		{"0123456789ABCDEF", true},
+		{"abc123", true},
+		{"", true}, // empty string has no non-hex chars
+		{"xyz", false},
+		{"123g", false},
+		{"hello-world", false},
+		{"12 34", false}, // space
+		{"12\n34", false}, // newline
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.input, func(t *testing.T) {
+			result := isHexString(tc.input)
+			if result != tc.expected {
+				t.Errorf("isHexString(%q) = %v, want %v", tc.input, result, tc.expected)
+			}
+		})
+	}
+}
+
+func TestIsNumeric(t *testing.T) {
+	tests := []struct {
+		input    string
+		expected bool
+	}{
+		{"123", true},
+		{"0", true},
+		{"9999999", true},
+		{" 123 ", true}, // whitespace trimmed
+		{"", false},
+		{"   ", false},
+		{"abc", false},
+		{"12.3", false},
+		{"-1", false},
+		{"1a2", false},
+		{"12 34", false},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.input, func(t *testing.T) {
+			result := isNumeric(tc.input)
+			if result != tc.expected {
+				t.Errorf("isNumeric(%q) = %v, want %v", tc.input, result, tc.expected)
+			}
+		})
+	}
+}
+
+func TestIsTruthy(t *testing.T) {
+	tests := []struct {
+		input    string
+		expected bool
+	}{
+		// Truthy values
+		{"1", true},
+		{"true", true},
+		{"TRUE", true},
+		{"True", true},
+		{"t", true},
+		{"T", true},
+		{"yes", true},
+		{"YES", true},
+		{"Yes", true},
+		{"y", true},
+		{"Y", true},
+		{"on", true},
+		{"ON", true},
+		{"On", true},
+		{" true ", true}, // with whitespace
+		{"\ttrue\n", true},
+
+		// Falsy values
+		{"0", false},
+		{"false", false},
+		{"FALSE", false},
+		{"no", false},
+		{"n", false},
+		{"off", false},
+		{"", false},
+		{"   ", false},
+		{"random", false},
+		{"2", false},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.input, func(t *testing.T) {
+			result := isTruthy(tc.input)
+			if result != tc.expected {
+				t.Errorf("isTruthy(%q) = %v, want %v", tc.input, result, tc.expected)
+			}
+		})
+	}
+}
+
+func TestContainerMarkers(t *testing.T) {
+	// Verify all expected markers are present
+	expectedMarkers := []string{
+		"docker",
+		"lxc",
+		"containerd",
+		"kubepods",
+		"podman",
+		"crio",
+		"libpod",
+		"lxcfs",
+	}
+
+	for _, expected := range expectedMarkers {
+		found := false
+		for _, marker := range containerMarkers {
+			if marker == expected {
+				found = true
+				break
+			}
+		}
+		if !found {
+			t.Errorf("Expected container marker %q not found", expected)
+		}
+	}
+}
+
+func TestInContainer(t *testing.T) {
+	// This is an integration test that depends on the runtime environment
+	// We can't mock the file system easily, but we can verify it doesn't panic
+	result := InContainer()
+	t.Logf("InContainer() = %v (depends on test environment)", result)
+}
+
+func TestDetectDockerContainerName(t *testing.T) {
+	// This is an integration test that depends on the runtime environment
+	result := DetectDockerContainerName()
+	t.Logf("DetectDockerContainerName() = %q (depends on test environment)", result)
+}
+
+func TestDetectLXCCTID(t *testing.T) {
+	// This is an integration test that depends on the runtime environment
+	result := DetectLXCCTID()
+	t.Logf("DetectLXCCTID() = %q (depends on test environment)", result)
+}