Bug 783987 - Test suite without hostile promises. r=Mossop

testing/xpcshell/xpcshell.ini

@@ -125,6 +125,7 @@ skip-if = os == "win" || os == "mac" || os == "os2"
 [include:netwerk/test/unit_ipc/xpcshell.ini]
 [include:netwerk/cookie/test/unit_ipc/xpcshell.ini]
 [include:toolkit/components/contentprefs/tests/unit_ipc/xpcshell.ini]
+[include:toolkit/addon-sdk/test/unit/xpcshell.ini]
 [include:uriloader/exthandler/tests/unit_ipc/xpcshell.ini]
 
 [include:modules/libmar/tests/unit/xpcshell.ini]

toolkit/addon-sdk/Makefile.in

@@ -20,4 +20,6 @@ EXTRA_JS_MODULES := \
   loader.js \
   $(NULL)
 
+TEST_DIRS += test
+
 include $(topsrcdir)/config/rules.mk

toolkit/addon-sdk/test/Makefile.in

@@ -0,0 +1,15 @@
+# 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/.
+
+DEPTH            = @DEPTH@
+topsrcdir        = @top_srcdir@
+srcdir           = @srcdir@
+VPATH            = @srcdir@
+relativesrcdir   = @relativesrcdir@
+
+MODULE           = test_addon_sdk
+XPCSHELL_TESTS = unit
+
+include $(DEPTH)/config/autoconf.mk
+include $(topsrcdir)/config/rules.mk

toolkit/addon-sdk/test/unit/head.js

@@ -0,0 +1,74 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+
+Components.utils.import("resource://gre/modules/commonjs/promise/core.js");
+
+let run_promise_tests = function run_promise_tests(tests, cb) {
+  let timer = Components.classes["@mozilla.org/timer;1"]
+     .createInstance(Components.interfaces.nsITimer);
+  let loop = function loop(index) {
+    if (index >= tests.length) {
+      if (cb) {
+        cb.call();
+      }
+      return;
+    }
+    do_print("Launching test " + (index + 1) + "/" + tests.length);
+    let test = tests[index];
+    // Execute from an empty stack
+    let next = function next() {
+      do_print("Test " + (index + 1) + "/" + tests.length + " complete");
+      do_execute_soon(function() {
+        loop(index + 1);
+      });
+    };
+    let result = test();
+    result.then(next, next);
+  };
+  return loop(0);
+};
+
+let make_promise_test = function(test) {
+  return function runtest() {
+    do_print("Test starting: " + test);
+    try {
+      let result = test();
+      if (result && "promise" in result) {
+        result = result.promise;
+      }
+      if (!result || !("then" in result)) {
+        let exn;
+        try {
+          do_throw("Test " + test + " did not return a promise: " + result);
+        } catch (x) {
+          exn = x;
+        }
+        return Promise.reject(exn);
+      }
+      // The test returns a promise
+      result = result.then(
+        // Test complete
+        function onResolve() {
+          do_print("Test complete: " + test);
+        },
+        // The test failed with an unexpected error
+        function onReject(err) {
+          let detail;
+          if (err && typeof err == "object" && "stack" in err) {
+            detail = err.stack;
+          } else {
+            detail = "(no stack)";
+          }
+          do_throw("Test " + test + " rejected with the following reason: "
+              + err + detail);
+      });
+      return result;
+    } catch (x) {
+      // The test failed because of an error outside of a promise
+      do_throw("Error in body of test " + test + ": " + x + " at " + x.stack);
+      return Promise.reject();
+    }
+  };
+};
+

toolkit/addon-sdk/test/unit/test_promise.js

@@ -0,0 +1,396 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+"use strict";
+
+let tests = [];
+
+// Utility function to observe an failures in a promise
+// This function is useful if the promise itself is
+// not returned.
+let observe_failures = function observe_failures(promise) {
+  promise.then(null, function onReject(reason) {
+    test.do_throw("Observed failure in test " + test + ": " + reason);
+  });
+};
+
+// Test that all observers are notified
+tests.push(make_promise_test(
+  function notification(test) {
+    // The size of the test
+    const SIZE = 10;
+    const RESULT = "this is an arbitrary value";
+
+    // Number of observers that yet need to be notified
+    let expected = SIZE;
+
+    // |true| once an observer has been notified
+    let notified = [];
+
+    // The promise observed
+    let source = Promise.defer();
+    let result = Promise.defer();
+
+    let install_observer = function install_observer(i) {
+      observe_failures(source.promise.then(
+        function onSuccess(value) {
+          do_check_true(!notified[i], "Ensuring that observer is notified at most once");
+          notified[i] = true;
+
+          do_check_eq(value, RESULT, "Ensuring that the observed value is correct");
+          if (--expected == 0) {
+            result.resolve();
+          }
+        }));
+    };
+
+    // Install a number of observers before resolving
+    let i;
+    for (i = 0; i < SIZE/2; ++i) {
+      install_observer(i);
+    }
+
+    source.resolve(RESULT);
+
+    // Install remaining observers
+    for(;i < SIZE; ++i) {
+      install_observer(i);
+    }
+
+    return result;
+  }));
+
+// Test that all observers are notified at most once, even if source
+// is resolved/rejected several times
+tests.push(make_promise_test(
+  function notification_once(test) {
+    // The size of the test
+    const SIZE = 10;
+    const RESULT = "this is an arbitrary value";
+
+    // Number of observers that yet need to be notified
+    let expected = SIZE;
+
+    // |true| once an observer has been notified
+    let notified = [];
+
+    // The promise observed
+    let observed = Promise.defer();
+    let result = Promise.defer();
+
+    let install_observer = function install_observer(i) {
+      observe_failures(observed.promise.then(
+        function onSuccess(value) {
+          do_check_true(!notified[i], "Ensuring that observer is notified at most once");
+          notified[i] = true;
+
+          do_check_eq(value, RESULT, "Ensuring that the observed value is correct");
+          if (--expected == 0) {
+            result.resolve();
+          }
+        }));
+    };
+
+    // Install a number of observers before resolving
+    let i;
+    for (i = 0; i < SIZE/2; ++i) {
+      install_observer(i);
+    }
+
+    observed.resolve(RESULT);
+
+    // Install remaining observers
+    for(;i < SIZE; ++i) {
+      install_observer(i);
+    }
+
+    // Resolve some more
+    for (i = 0; i < 10; ++i) {
+      observed.resolve(RESULT);
+      observed.reject();
+    }
+
+    return result;
+  }));
+
+// Test that throwing an exception from a onResolve listener
+// does not prevent other observers from receiving the notification
+// of success.
+tests.push(
+  make_promise_test(function exceptions_do_not_stop_notifications(test)  {
+    let source = Promise.defer();
+
+    let exception_thrown = false;
+    let exception_content = new Error("Boom!");
+
+    let observer_1 = source.promise.then(
+      function onResolve() {
+        exception_thrown = true;
+        throw exception_content;
+      });
+
+    let observer_2 = source.promise.then(
+      function onResolve() {
+        do_check_true(exception_thrown, "Second observer called after first observer has thrown");
+      }
+    );
+
+    let result = observer_1.then(
+      function onResolve() {
+        do_throw("observer_1 should not have resolved");
+      },
+      function onReject(reason) {
+        do_check_true(reason == exception_content, "Obtained correct rejection");
+      }
+    );
+
+    source.resolve();
+    return result;
+  }
+));
+
+// Test that, once a promise is resolved, further resolve/reject
+// are ignored.
+tests.push(
+  make_promise_test(function subsequent_resolves_are_ignored(test) {
+    let deferred = Promise.defer();
+    deferred.resolve(1);
+    deferred.resolve(2);
+    deferred.reject(3);
+
+    let result = deferred.promise.then(
+      function onResolve(value) {
+        do_check_eq(value, 1, "Resolution chose the first value");
+      },
+      function onReject(reason) {
+        do_throw("Obtained a rejection while the promise was already resolved");
+      }
+    );
+
+    return result;
+  }));
+
+// Test that, once a promise is rejected, further resolve/reject
+// are ignored.
+tests.push(
+  make_promise_test(function subsequent_rejects_are_ignored(test) {
+    let deferred = Promise.defer();
+    deferred.reject(1);
+    deferred.reject(2);
+    deferred.resolve(3);
+
+    let result = deferred.promise.then(
+      function onResolve() {
+        do_throw("Obtained a resolution while the promise was already rejected");
+      },
+      function onReject(reason) {
+        do_check_eq(reason, 1, "Rejection chose the first value");
+      }
+    );
+
+    return result;
+  }));
+
+// Test that returning normally from a rejection recovers from the error
+// and that listeners are informed of a success.
+tests.push(
+  make_promise_test(function recovery(test) {
+    let boom = new Error("Boom!");
+    let deferred = Promise.defer();
+    const RESULT = "An arbitrary value";
+
+    let promise = deferred.promise.then(
+      function onResolve() {
+        do_throw("A rejected promise should not resolve");
+      },
+      function onReject(reason) {
+        do_check_true(reason == boom, "Promise was rejected with the correct error");
+        return RESULT;
+      }
+    );
+
+    promise = promise.then(
+      function onResolve(value) {
+        do_check_eq(value, RESULT, "Promise was recovered with the correct value");
+      }
+    );
+
+    deferred.reject(boom);
+    return promise;
+  }));
+
+// Test that returning a resolved promise from a onReject causes a resolution
+// (recovering from the error) and that returning a rejected promise
+// from a onResolve listener causes a rejection (raising an error).
+tests.push(
+  make_promise_test(function recovery_with_promise(test) {
+    let boom = new Error("Arbitrary error");
+    let deferred = Promise.defer();
+    const RESULT = "An arbitrary value";
+    const boom2 = new Error("Another arbitrary error");
+
+    // return a resolved promise from a onReject listener
+    let promise = deferred.promise.then(
+      function onResolve() {
+        do_throw("A rejected promise should not resolve");
+      },
+      function onReject(reason) {
+        do_check_true(reason == boom, "Promise was rejected with the correct error");
+        return Promise.resolve(RESULT);
+      }
+    );
+
+    // return a rejected promise from a onResolve listener
+    promise = promise.then(
+      function onResolve(value) {
+        do_check_eq(value, RESULT, "Promise was recovered with the correct value");
+        return Promise.reject(boom2);
+      }
+    );
+
+    promise = promise.then(
+      null,
+      function onReject(reason) {
+        do_check_eq(reason, boom2, "Rejection was propagated with the correct " +
+                "reason, through a promise");
+      }
+    );
+
+    deferred.reject(boom);
+    return promise;
+  }));
+
+// Test that we can resolve with promises of promises
+tests.push(
+  make_promise_test(function test_propagation(test) {
+    const RESULT = "Yet another arbitrary value";
+    let d1 = Promise.defer();
+    let d2 = Promise.defer();
+    let d3 = Promise.defer();
+
+    d3.resolve(d2.promise);
+    d2.resolve(d1.promise);
+    d1.resolve(RESULT);
+
+    return d3.promise.then(
+      function onSuccess(value) {
+        do_check_eq(value, RESULT, "Resolution with a promise eventually yielded "
+                + " the correct result");
+      }
+    );
+  }));
+
+// Test sequences of |then|
+tests.push(
+  make_promise_test(function test_chaining(test) {
+    let error_1 = new Error("Error 1");
+    let error_2 = new Error("Error 2");
+    let result_1 = "First result";
+    let result_2 = "Second result";
+    let result_3 = "Third result";
+
+    let source = Promise.defer();
+
+    let promise = source.promise.then().then();
+
+    source.resolve(result_1);
+
+    // Check that result_1 is correctly propagated
+    promise = promise.then(
+      function onSuccess(result) {
+        do_check_eq(result, result_1, "Result was propagated correctly through " +
+                " several applications of |then|");
+        return result_2;
+      }
+    );
+
+    // Check that returning from the promise produces a resolution
+    promise = promise.then(
+      null,
+      function onReject() {
+        do_throw("Incorrect rejection");
+      }
+    );
+
+    // ... and that the check did not alter the value
+    promise = promise.then(
+      function onResolve(value) {
+        do_check_eq(value, result_2, "Result was propagated correctly once again");
+      }
+    );
+
+    // Now the same kind of tests for rejections
+    promise = promise.then(
+      function onResolve() {
+        throw error_1;
+      }
+    );
+
+    promise = promise.then(
+      function onResolve() {
+        do_throw("Incorrect resolution: the exception should have caused a rejection");
+      }
+    );
+
+    promise = promise.then(
+      null,
+      function onReject(reason) {
+        do_check_true(reason == error_1, "Reason was propagated correctly");
+        throw error_2;
+      }
+    );
+
+    promise = promise.then(
+      null,
+      function onReject(reason) {
+        do_check_true(reason == error_2, "Throwing an error altered the reason " +
+            "as expected");
+        return result_3;
+      }
+    );
+
+    promise = promise.then(
+      function onResolve(result) {
+        do_check_eq(result, result_3, "Error was correctly recovered");
+      }
+    );
+
+    return promise;
+  }));
+
+// Test that resolving with a rejected promise actually rejects
+tests.push(
+  make_promise_test(function resolve_to_rejected(test) {
+    let source = Promise.defer();
+    let error = new Error("Boom");
+
+    let promise = source.promise.then(
+      function onResolve() {
+        do_throw("Incorrect call to onResolve listener");
+      },
+      function onReject(reason) {
+        do_check_eq(reason, error, "Rejection lead to the expected reason");
+      }
+    );
+
+    source.resolve(Promise.reject(error));
+
+    return promise;
+  }));
+
+// Test that Promise.resolve resolves as expected
+tests.push(
+  make_promise_test(function test_resolve(test) {
+    const RESULT = "arbitrary value";
+    let promise = Promise.resolve(RESULT).then(
+      function onResolve(result) {
+        do_check_eq(result, RESULT, "Promise.resolve propagated the correct result");
+      }
+    );
+    return promise;
+  }));
+
+function run_test()
+{
+  do_test_pending();
+  run_promise_tests(tests, do_test_finished);
+}

toolkit/addon-sdk/test/unit/xpcshell.ini

@@ -0,0 +1,5 @@
+[DEFAULT]
+head = head.js
+tail = 
+
+[test_promise.js]