fixing style

internal/web/theme_origin_test.go

@@ -0,0 +1,75 @@
+package web
+
+import (
+	"strings"
+	"testing"
+)
+
+const shell = `<!doctype html>
+<html lang="en">
+  <head>
+    <title>Urpi's backlog</title>
+  </head>
+  <body><div id="root"></div><script type="module" src="/src/main.tsx"></script></body>
+</html>`
+
+// TestThemeLinesAreAddedWhenConfigured is the whole feature: the contract reaches
+// the page.
+func TestThemeLinesAreAddedWhenConfigured(t *testing.T) {
+	got := string(applyThemeOrigin([]byte(shell), "https://bananas-dev.urpi.be"))
+
+	if !strings.Contains(got, `href="https://bananas-dev.urpi.be/rt/v1/contract.css"`) {
+		t.Errorf("the contract stylesheet was not added:\n%s", got)
+	}
+	if !strings.Contains(got, `src="https://bananas-dev.urpi.be/rt/v1/components.js"`) {
+		t.Errorf("the control module was not added:\n%s", got)
+	}
+	// Injected before </head>, so the stylesheet is parsed before the body renders. A
+	// contract that arrives late shows a flash of the fallback palette.
+	headClose := strings.Index(got, "</head>")
+	link := strings.Index(got, "contract.css")
+	if link < 0 || link > headClose {
+		t.Errorf("the contract link is not inside the head (link=%d, head=%d)", link, headClose)
+	}
+	// The application script must survive untouched.
+	if !strings.Contains(got, `src="/src/main.tsx"`) {
+		t.Error("the application script was altered")
+	}
+}
+
+func TestThemeOriginTrailingSlashIsTrimmed(t *testing.T) {
+	for _, base := range []string{
+		"https://bananas-dev.urpi.be/",
+		"https://bananas-dev.urpi.be///",
+	} {
+		got := string(applyThemeOrigin([]byte(shell), base))
+		if strings.Contains(got, "be//") {
+			t.Errorf("base %q produced a doubled slash:\n%s", base, got)
+		}
+	}
+}
+
+// TestNothingIsAddedWhenNoOriginIsConfigured is the branch that matters most: an
+// unset or blank origin must leave the page byte-identical, because the stylesheet's
+// var() fallbacks are what carry the application in that case.
+func TestNothingIsAddedWhenNoOriginIsConfigured(t *testing.T) {
+	for _, base := range []string{"", "   ", "\t", "/"} {
+		got := applyThemeOrigin([]byte(shell), base)
+		if string(got) != shell {
+			t.Errorf("base %q modified the shell:\n%s", base, got)
+		}
+		if strings.Contains(string(got), "rt/v1") {
+			t.Errorf("base %q left a contract reference behind:\n%s", base, got)
+		}
+	}
+}
+
+// TestShellWithoutHeadIsUnchanged covers a malformed shell. Returning the input
+// unchanged is better than corrupting it, and better than a 500 on a page that would
+// otherwise have rendered.
+func TestShellWithoutHeadIsUnchanged(t *testing.T) {
+	odd := []byte("<html><body>no head</body></html>")
+	if got := applyThemeOrigin(odd, "https://bananas-dev.urpi.be"); string(got) != string(odd) {
+		t.Errorf("a shell with no head was modified:\n%s", got)
+	}
+}