1 files changed, 99 insertions, 0 deletions
diff --git a/netwerk/test/unit/test_header_Accept-Language.js b/netwerk/test/unit/test_header_Accept-Language.js
new file mode 100644
index 0000000000..b00e02d13b
--- /dev/null
+++ b/netwerk/test/unit/test_header_Accept-Language.js
@@ -0,0 +1,99 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+//
+//  HTTP Accept-Language header test
+//
+
+"use strict";
+
+var testpath = "/bug672448";
+
+function run_test() {
+  let intlPrefs = Services.prefs.getBranch("intl.");
+
+  // Save old value of preference for later.
+  let oldPref = intlPrefs.getCharPref("accept_languages");
+
+  // Test different numbers of languages, to test different fractions.
+  let acceptLangTests = [
+    "qaa", // 1
+    "qaa,qab", // 2
+    "qaa,qab,qac,qad", // 4
+    "qaa,qab,qac,qad,qae,qaf,qag,qah", // 8
+    "qaa,qab,qac,qad,qae,qaf,qag,qah,qai,qaj", // 10
+    "qaa,qab,qac,qad,qae,qaf,qag,qah,qai,qaj,qak", // 11
+    "qaa,qab,qac,qad,qae,qaf,qag,qah,qai,qaj,qak,qal,qam,qan,qao,qap,qaq,qar,qas,qat,qau", // 21
+    oldPref, // Restore old value of preference (and test it).
+  ];
+
+  let acceptLangTestsNum = acceptLangTests.length;
+
+  for (let i = 0; i < acceptLangTestsNum; i++) {
+    // Set preference to test value.
+    intlPrefs.setCharPref("accept_languages", acceptLangTests[i]);
+
+    // Test value.
+    test_accepted_languages();
+  }
+}
+
+function test_accepted_languages() {
+  let channel = setupChannel(testpath);
+
+  let AcceptLanguage = channel.getRequestHeader("Accept-Language");
+
+  let acceptedLanguages = AcceptLanguage.split(",");
+
+  let acceptedLanguagesLength = acceptedLanguages.length;
+
+  for (let i = 0; i < acceptedLanguagesLength; i++) {
+    let qualityValue;
+
+    try {
+      // The q-value must conform to the definition in HTTP/1.1 Section 3.9.
+      [, , qualityValue] = acceptedLanguages[i]
+        .trim()
+        .match(/^([a-z0-9_-]*?)(?:;q=(1(?:\.0{0,3})?|0(?:\.[0-9]{0,3})))?$/i);
+    } catch (e) {
+      do_throw("Invalid language tag or quality value: " + e);
+    }
+
+    if (i == 0) {
+      // The first language shouldn't have a quality value.
+      Assert.equal(qualityValue, undefined);
+    } else {
+      let decimalPlaces;
+
+      // When the number of languages is small, we keep the quality value to only one decimal place.
+      // Otherwise, it can be up to two decimal places.
+      if (acceptedLanguagesLength < 10) {
+        Assert.ok(qualityValue.length == 3);
+
+        decimalPlaces = 1;
+      } else {
+        Assert.ok(qualityValue.length >= 3);
+        Assert.ok(qualityValue.length <= 4);
+
+        decimalPlaces = 2;
+      }
+
+      // All the other languages should have an evenly-spaced quality value.
+      Assert.equal(
+        parseFloat(qualityValue).toFixed(decimalPlaces),
+        (1.0 - (1 / acceptedLanguagesLength) * i).toFixed(decimalPlaces)
+      );
+    }
+  }
+}
+
+function setupChannel(path) {
+  let chan = NetUtil.newChannel({
+    uri: "http://localhost:4444" + path,
+    loadUsingSystemPrincipal: true,
+  });
+
+  chan.QueryInterface(Ci.nsIHttpChannel);
+  return chan;
+}