package proxy
import (
"bytes"
"strings"
"testing"
)
func TestShouldInject(t *testing.T) {
tests := []struct {
contentType string
expected bool
}{
{"text/html", true},
{"text/html; charset=utf-8", true},
{"TEXT/HTML", true},
{"application/json", false},
{"text/plain", false},
{"application/javascript", false},
{"image/png", false},
}
for _, tt := range tests {
t.Run(tt.contentType, func(t *testing.T) {
result := ShouldInject(tt.contentType)
if result != tt.expected {
t.Errorf("ShouldInject(%q) = %v, expected %v", tt.contentType, result, tt.expected)
}
})
}
}
func TestInjectInstrumentation_BeforeHeadClose(t *testing.T) {
html := []byte(`<!DOCTYPE html>
<html>
<head>
<title>Test</title>
</head>
<body>
<h1>Hello World</h1>
</body>
</html>`)
result := InjectInstrumentation(html, 8080)
// Should inject before </head>
if !bytes.Contains(result, []byte("<script>")) {
t.Error("Script not injected")
}
// Script should appear before </head>
scriptIdx := bytes.Index(result, []byte("<script>"))
headCloseIdx := bytes.Index(result, []byte("</head>"))
if scriptIdx == -1 {
t.Error("Script tag not found")
}
if headCloseIdx == -1 {
t.Error("</head> tag not found")
}
if scriptIdx >= headCloseIdx {
t.Error("Script should be injected before </head>")
}
}
func TestInjectInstrumentation_AfterHeadOpen(t *testing.T) {
html := []byte(`<!DOCTYPE html>
<html>
<head><title>Test</title>
<body>
<h1>Hello World</h1>
</body>
</html>`)
result := InjectInstrumentation(html, 8080)
// Should inject after <head>
if !bytes.Contains(result, []byte("<script>")) {
t.Error("Script not injected")
}
// Script should appear after <head>
headOpenIdx := bytes.Index(result, []byte("<head>"))
scriptIdx := bytes.Index(result, []byte("<script>"))
if headOpenIdx == -1 {
t.Error("<head> tag not found")
}
if scriptIdx == -1 {
t.Error("Script tag not found")
}
if scriptIdx <= headOpenIdx+6 {
t.Error("Script should be injected after <head>")
}
}
func TestInjectInstrumentation_AfterBody(t *testing.T) {
html := []byte(`<!DOCTYPE html>
<html>
<body>
<h1>Hello World</h1>
</body>
</html>`)
result := InjectInstrumentation(html, 8080)
// Should inject after <body>
if !bytes.Contains(result, []byte("<script>")) {
t.Error("Script not injected")
}
// Script should appear after <body>
bodyOpenIdx := bytes.Index(result, []byte("<body>"))
scriptIdx := bytes.Index(result, []byte("<script>"))
if bodyOpenIdx == -1 {
t.Error("<body> tag not found")
}
if scriptIdx == -1 {
t.Error("Script tag not found")
}
if scriptIdx <= bodyOpenIdx+6 {
t.Error("Script should be injected after <body>")
}
}
func TestInjectInstrumentation_BodyWithAttributes(t *testing.T) {
html := []byte(`<!DOCTYPE html>
<html>
<body class="page" id="main">
<h1>Hello World</h1>
</body>
</html>`)
result := InjectInstrumentation(html, 8080)
// Should inject after <body ...>
if !bytes.Contains(result, []byte("<script>")) {
t.Error("Script not injected")
}
// Should still contain original body tag
if !bytes.Contains(result, []byte(`<body class="page" id="main">`)) {
t.Error("Original body tag modified")
}
}
func TestInjectInstrumentation_MinimalHTML(t *testing.T) {
html := []byte(`<html><body>Hello</body></html>`)
result := InjectInstrumentation(html, 8080)
// Should inject somewhere
if !bytes.Contains(result, []byte("<script>")) {
t.Error("Script not injected")
}
}
func TestInjectInstrumentation_NoHTML(t *testing.T) {
html := []byte(`Hello World`)
result := InjectInstrumentation(html, 8080)
// Should prepend script as last resort
if !bytes.Contains(result, []byte("<script>")) {
t.Error("Script not injected")
}
// Script should be at the beginning (checking for html2canvas script tag)
scriptIdx := bytes.Index(result, []byte("<script"))
if scriptIdx == -1 {
t.Error("Script tag not found")
}
if scriptIdx > 10 { // Allow for some whitespace/newlines
t.Error("Script should be prepended when no HTML tags found")
}
// Original content should still be there
if !bytes.Contains(result, []byte("Hello World")) {
t.Error("Original content missing")
}
}
func TestInjectInstrumentation_ScriptContent(t *testing.T) {
html := []byte(`<!DOCTYPE html>
<html>
<head></head>
<body></body>
</html>`)
result := InjectInstrumentation(html, 8080)
resultStr := string(result)
// Check for key instrumentation features
expectedFeatures := []string{
"WebSocket",
"error",
"performance",
"window.addEventListener",
"unhandledrejection",
"window.location.host", // Should use relative URL with current host
"__devtool_metrics",
}
for _, feature := range expectedFeatures {
if !strings.Contains(resultStr, feature) {
t.Errorf("Injected script missing feature: %s", feature)
}
}
}
func TestInjectInstrumentation_PreservesOriginalContent(t *testing.T) {
html := []byte(`<!DOCTYPE html>
<html>
<head>
<title>Test Page</title>
<meta charset="utf-8">
</head>
<body>
<h1>Hello World</h1>
<p>This is a test.</p>
</body>
</html>`)
result := InjectInstrumentation(html, 8080)
// Original content should still be present
expectedContent := []string{
"<!DOCTYPE html>",
"<title>Test Page</title>",
"<meta charset=\"utf-8\">",
"<h1>Hello World</h1>",
"<p>This is a test.</p>",
}
resultStr := string(result)
for _, content := range expectedContent {
if !strings.Contains(resultStr, content) {
t.Errorf("Original content missing: %s", content)
}
}
}
func TestInjectInstrumentation_DifferentPorts(t *testing.T) {
html := []byte(`<!DOCTYPE html><html><head></head></html>`)
ports := []int{8080, 3000, 9000}
for _, port := range ports {
result := InjectInstrumentation(html, port)
resultStr := string(result)
// With the new relative URL approach, the script should use window.location.host
// which automatically includes the current port, making the port parameter obsolete
expectedPattern := "window.location.host + '/__devtool_metrics'"
if !strings.Contains(resultStr, expectedPattern) {
t.Errorf("Script should use window.location.host for WebSocket URL (port-independent)")
}
}
}
