1 files changed, 82 insertions, 0 deletions
diff --git a/devtools/shared/commands/resource/tests/browser_resources_stylesheets_header.js b/devtools/shared/commands/resource/tests/browser_resources_stylesheets_header.js
new file mode 100644
index 0000000000..29263d887b
--- /dev/null
+++ b/devtools/shared/commands/resource/tests/browser_resources_stylesheets_header.js
@@ -0,0 +1,82 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Test that we do get the appropriate stylesheet content when the stylesheet is only
+// served based on the Accept: text/css header
+
+add_task(async function () {
+  const httpServer = createTestHTTPServer();
+
+  httpServer.registerContentType("html", "text/html");
+
+  httpServer.registerPathHandler("/index.html", function (request, response) {
+    response.setStatusLine(request.httpVersion, 200, "OK");
+    response.write(`
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>Test stylesheet</title>
+<link href="/test/" rel="stylesheet" type="text/css"/>
+<script src="/test/"></script>
+<h1>Hello</h1>
+  `);
+  });
+
+  let resourceUrlCalls = 0;
+  // The /test/ URL should be called:
+  // - once by the content page to load the <link>
+  // - once by the content page to load the <script>
+  // - once by DevTools to fetch the stylesheet text
+  // (we could probably optimize this so we only call once)
+  const expectedResourceUrlCalls = 3;
+
+  const styleSheetText = `body { background-color: tomato; }`;
+  httpServer.registerPathHandler("/test/", function (request, response) {
+    resourceUrlCalls++;
+    response.setStatusLine(request.httpVersion, 200, "OK");
+
+    if (request.getHeader("Accept").startsWith("text/css")) {
+      response.setHeader("Content-Type", "text/css", false);
+      response.write(styleSheetText);
+      return;
+    }
+    response.setHeader("Content-Type", "application/javascript", false);
+    response.write(`/* NOT A STYLESHEET */`);
+  });
+  const port = httpServer.identity.primaryPort;
+  const TEST_URL = `http://localhost:${port}/index.html`;
+
+  info("Check resource available feature of the ResourceCommand");
+  const tab = await addTab(TEST_URL);
+
+  const { client, resourceCommand, targetCommand } = await initResourceCommand(
+    tab
+  );
+
+  info("Check whether ResourceCommand gets existing stylesheet");
+  const availableResources = [];
+  await resourceCommand.watchResources([resourceCommand.TYPES.STYLESHEET], {
+    onAvailable: resources => availableResources.push(...resources),
+  });
+  is(
+    availableResources.length,
+    1,
+    "We have the expected number of stylesheets"
+  );
+
+  is(
+    await getStyleSheetResourceText(availableResources[0]),
+    styleSheetText,
+    "Got expected text for the stylesheet"
+  );
+
+  is(
+    resourceUrlCalls,
+    expectedResourceUrlCalls,
+    "The /test URL was called the number of time we expected"
+  );
+
+  targetCommand.destroy();
+  await client.close();
+});