--- a/toolkit/components/prompts/test/test_modal_prompts.html
+++ b/toolkit/components/prompts/test/test_modal_prompts.html
@@ -27,17 +27,17 @@ function pollDialog(okButton) {
 
     ok(true, "dialog button is enabled now");
     pollTimer.cancel();
     pollTimer = null;
     okButton.click();
     didDialog = true;
 }
 
-function checkExpectedState(ui, state) {
+function checkExpectedState(ui, state, action) {
 
     // XXX check title? OS X has title in content
     is(ui.infoBody.textContent,       state.msg,         "Checking expected message");
     is(ui.loginContainer.hidden,      state.textHidden,  "Checking textbox visibility");
     is(ui.password1Container.hidden,  state.passHidden,  "Checking passbox visibility");
     is(ui.checkboxContainer.hidden,   state.checkHidden, "Checking checkbox visibility");
     is(ui.checkbox.label,             state.checkMsg,    "Checking checkbox label");
     is(ui.checkbox.checked,           state.checked,     "Checking checkbox checked");
@@ -61,45 +61,87 @@ function checkExpectedState(ui, state) {
     is(isDefaultButton(ui.button2), shouldBeDefault, "checking button2 default");
 
     let fm = Cc["@mozilla.org/focus-manager;1"].
              getService(Ci.nsIFocusManager);
     let e = fm.focusedElement;
     ok(true, "focused element is a " + (e ? e.localName : "<null>"));
     if (isLinux && !e) {
         todo(false, "Focus seems missing on Linux");
-        return;
+    } else {
+        if (isOSX && state.focused && state.focused.localName == "button")
+            ok(SpecialPowers.compare(ui.infoBody, e), "buttons don't focus on OS X");
+        else if (state.focused)
+            ok(SpecialPowers.compare(state.focused, e), "Checking focused element");
+        else
+            is(e, null, "Not expecting a focused element");
+    }
+
+
+    /* Actions */
+
+
+    if (action.setCheckbox) {
+        // Annoyingly, the prompt code is driven by oncommand.
+        ui.checkbox.setChecked(true);
+        ui.checkbox.doCommand();
+    }
+
+    if (action.textField) {
+        ui.loginTextbox.setAttribute("value", action.textField);
+    }
+
+    if (action.passField) {
+        ui.password1Textbox.setAttribute("value", action.passField);
     }
 
-    if (isOSX && state.focused && state.focused.localName == "button")
-        ok(SpecialPowers.compare(ui.infoBody, e), "buttons don't focus on OS X");
-    else if (state.focused)
-        ok(SpecialPowers.compare(state.focused, e), "Checking focused element");
-    else
-        is(e, null, "Not expecting a focused element");
+    switch (action.buttonClick) {
+        case "ok":
+        case 0:
+            ui.button0.click();
+            break;
+        case "cancel":
+        case 1:
+            ui.button1.click();
+            break;
+        case 2:
+            ui.button2.click();
+            break;
+        case "pollOK":
+            // Buttons are disabled at the moment, poll until they're reenabled.
+            // Can't use setInterval here, because the window's in a modal state
+            // and thus DOM events are suppressed.
+            pollTimer = Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer);
+            pollTimer.initWithCallback(SpecialPowers.wrapCallback(function() {
+              pollDialog(ui.button0);
+            }),
+                                   100, Ci.nsITimer.TYPE_REPEATING_SLACK);
+            break;
+        default:
+            ok(false, "checkExpectedState action listed unknown button.")
+    }
+
+    if (action.buttonClick != "pollOK")
+        didDialog = true;
 }
 
 
 /*
  * handleDialog
  *
  * Invoked a short period of time after calling startCallbackTimer(), and
  * allows testing the actual prompt dialog while it's being displayed. Tests
  * should call startCallbackTimer() each time the auth dialog is expected (the
  * timer is a one-shot).
  */
 function handleDialog(ui, testNum) {
     ok(true, "--- handleDialog for test " + testNum +
              " --- (isTabModal=" + isTabModal + ", usePromptService=" + usePromptService + ")");
 
-    let textField = ui.loginTextbox;
-    let passField = ui.password1Textbox;
-    let checkbox  = ui.checkbox;
-    let clickOK   = true;
-    let state;
+    let state, action;
 
     switch(testNum) {
       case 1:
         // Alert
         state = {
             msg   : "This is the alert text.",
             title : "TestTitle",
             iconClass   : "alert-icon",
@@ -108,17 +150,20 @@ function handleDialog(ui, testNum) {
             checkHidden : true,
             textValue   : "",
             passValue   : "",
             checkMsg    : "",
             checked     : false,
             focused     : ui.button0,
             defButton   : ui.button0,
         };
-        checkExpectedState(ui, state);
+        action = {
+            buttonClick: "ok",
+        };
+        checkExpectedState(ui, state, action);
         break;
 
       case 2:
         // AlertCheck (null checkbox label, so it's hidden)
         state = {
             msg   : "This is the alertCheck text.",
             title : "TestTitle",
             iconClass   : "alert-icon",
@@ -127,17 +172,20 @@ function handleDialog(ui, testNum) {
             checkHidden : true,
             textValue   : "",
             passValue   : "",
             checkMsg    : "",
             checked     : false,
             focused     : ui.button0,
             defButton   : ui.button0,
         };
-        checkExpectedState(ui, state);
+        action = {
+            buttonClick: "ok",
+        };
+        checkExpectedState(ui, state, action);
         break;
 
       case 3:
         // AlertCheck
         state = {
             msg   : "This is the alertCheck text.",
             title : "TestTitle",
             iconClass   : "alert-icon",
@@ -146,21 +194,21 @@ function handleDialog(ui, testNum) {
             checkHidden : false,
             textValue   : "",
             passValue   : "",
             checkMsg    : "Check me out!",
             checked     : false,
             focused     : ui.button0,
             defButton   : ui.button0,
         };
-        checkExpectedState(ui, state);
-
-        // XXX dumb. old code driven by oncommand.
-        checkbox.setChecked(true);
-        checkbox.doCommand();
+        action = {
+            buttonClick: "ok",
+            setCheckbox: true,
+        };
+        checkExpectedState(ui, state, action);
         break;
 
       case 4:
         // Confirm (ok)
         state = {
             msg   : "This is the confirm text.",
             title : "TestTitle",
             iconClass   : "question-icon",
@@ -169,17 +217,20 @@ function handleDialog(ui, testNum) {
             checkHidden : true,
             textValue   : "",
             passValue   : "",
             checkMsg    : "",
             checked     : false,
             focused     : ui.button0,
             defButton   : ui.button0,
         };
-        checkExpectedState(ui, state);
+        action = {
+            buttonClick: "ok",
+        };
+        checkExpectedState(ui, state, action);
         break;
 
       case 5:
         // Confirm (cancel)
         state = {
             msg   : "This is the confirm text.",
             title : "TestTitle",
             iconClass   : "question-icon",
@@ -188,18 +239,20 @@ function handleDialog(ui, testNum) {
             checkHidden : true,
             textValue   : "",
             passValue   : "",
             checkMsg    : "",
             checked     : false,
             focused     : ui.button0,
             defButton   : ui.button0,
         };
-        checkExpectedState(ui, state);
-        clickOK = false;
+        action = {
+            buttonClick: "cancel",
+        };
+        checkExpectedState(ui, state, action);
         break;
 
       case 6:
         // ConfirmCheck (no checkbox, ok)
         state = {
             msg   : "This is the confirmCheck text.",
             title : "TestTitle",
             iconClass   : "question-icon",
@@ -208,17 +261,20 @@ function handleDialog(ui, testNum) {
             checkHidden : true,
             textValue   : "",
             passValue   : "",
             checkMsg    : "",
             checked     : false,
             focused     : ui.button0,
             defButton   : ui.button0,
         };
-        checkExpectedState(ui, state);
+        action = {
+            buttonClick: "ok",
+        };
+        checkExpectedState(ui, state, action);
         break;
 
       case 7:
         // ConfirmCheck (no checkbox, cancel)
         state = {
             msg   : "This is the confirmCheck text.",
             title : "TestTitle",
             iconClass   : "question-icon",
@@ -227,18 +283,20 @@ function handleDialog(ui, testNum) {
             checkHidden : true,
             textValue   : "",
             passValue   : "",
             checkMsg    : "",
             checked     : false,
             focused     : ui.button0,
             defButton   : ui.button0,
         };
-        checkExpectedState(ui, state);
-        clickOK = false;
+        action = {
+            buttonClick: "cancel",
+        };
+        checkExpectedState(ui, state, action);
         break;
 
       case 8:
         // ConfirmCheck (ok)
         state = {
             msg   : "This is the confirmCheck text.",
             title : "TestTitle",
             iconClass   : "question-icon",
@@ -247,21 +305,21 @@ function handleDialog(ui, testNum) {
             checkHidden : false,
             textValue   : "",
             passValue   : "",
             checkMsg    : "Check me out!",
             checked     : false,
             focused     : ui.button0,
             defButton   : ui.button0,
         };
-        checkExpectedState(ui, state);
-
-        // XXX dumb. old code driven by oncommand.
-        checkbox.setChecked(true);
-        checkbox.doCommand();
+        action = {
+            buttonClick: "ok",
+            setCheckbox: true,
+        };
+        checkExpectedState(ui, state, action);
         break;
 
       case 9:
         // ConfirmCheck (cancel)
         state = {
             msg   : "This is the confirmCheck text.",
             title : "TestTitle",
             iconClass   : "question-icon",
@@ -270,22 +328,21 @@ function handleDialog(ui, testNum) {
             checkHidden : false,
             textValue   : "",
             passValue   : "",
             checkMsg    : "Check me out!",
             checked     : false,
             focused     : ui.button0,
             defButton   : ui.button0,
         };
-        checkExpectedState(ui, state);
-
-        clickOK = false;
-        // XXX dumb. old code driven by oncommand.
-        checkbox.setChecked(true);
-        checkbox.doCommand();
+        action = {
+            buttonClick: "cancel",
+            setCheckbox: true,
+        };
+        checkExpectedState(ui, state, action);
         break;
 
       case 10:
         // Prompt (ok, no default text)
         state = {
             msg   : "This is the prompt text.",
             title : "TestTitle",
             iconClass   : "question-icon",
@@ -294,18 +351,21 @@ function handleDialog(ui, testNum) {
             checkHidden : true,
             textValue   : "",
             passValue   : "",
             checkMsg    : "",
             checked     : false,
             focused     : ui.loginTextbox.inputField,
             defButton   : ui.button0,
         };
-        checkExpectedState(ui, state);
-        textField.setAttribute("value", "bacon");
+        action = {
+            buttonClick : "ok",
+            textField   : "bacon",
+        };
+        checkExpectedState(ui, state, action);
         break;
 
       case 11:
         // Prompt (ok, default text)
         state = {
             msg   : "This is the prompt text.",
             title : "TestTitle",
             iconClass   : "question-icon",
@@ -314,17 +374,20 @@ function handleDialog(ui, testNum) {
             checkHidden : true,
             textValue   : "kittens",
             passValue   : "",
             checkMsg    : "",
             checked     : false,
             focused     : ui.loginTextbox.inputField,
             defButton   : ui.button0,
         };
-        checkExpectedState(ui, state);
+        action = {
+            buttonClick: "ok",
+        };
+        checkExpectedState(ui, state, action);
         break;
 
       case 12:
         // Prompt (cancel, default text)
         state = {
             msg   : "This is the prompt text.",
             title : "TestTitle",
             iconClass   : "question-icon",
@@ -333,18 +396,20 @@ function handleDialog(ui, testNum) {
             checkHidden : true,
             textValue   : "puppies",
             passValue   : "",
             checkMsg    : "",
             checked     : false,
             focused     : ui.loginTextbox.inputField,
             defButton   : ui.button0,
         };
-        checkExpectedState(ui, state);
-        clickOK = false;
+        action = {
+            buttonClick: "cancel",
+        };
+        checkExpectedState(ui, state, action);
         break;
 
       case 13:
         // Prompt (cancel, default text modified)
         state = {
             msg   : "This is the prompt text.",
             title : "TestTitle",
             iconClass   : "question-icon",
@@ -353,19 +418,21 @@ function handleDialog(ui, testNum) {
             checkHidden : true,
             textValue   : "puppies",
             passValue   : "",
             checkMsg    : "",
             checked     : false,
             focused     : ui.loginTextbox.inputField,
             defButton   : ui.button0,
         };
-        checkExpectedState(ui, state);
-        textField.setAttribute("value", "bacon");
-        clickOK = false;
+        action = {
+            buttonClick : "cancel",
+            textField   : "bacon",
+        };
+        checkExpectedState(ui, state, action);
         break;
 
       case 14:
         // Prompt (ok, with checkbox)
         state = {
             msg   : "This is the prompt text.",
             title : "TestTitle",
             iconClass   : "question-icon",
@@ -374,21 +441,21 @@ function handleDialog(ui, testNum) {
             checkHidden : false,
             textValue   : "tribbles",
             passValue   : "",
             checkMsg    : "Check me out!",
             checked     : false,
             focused     : ui.loginTextbox.inputField,
             defButton   : ui.button0,
         };
-        checkExpectedState(ui, state);
-
-        // XXX dumb. old code driven by oncommand.
-        checkbox.setChecked(true);
-        checkbox.doCommand();
+        action = {
+            buttonClick: "ok",
+            setCheckbox: true,
+        };
+        checkExpectedState(ui, state, action);
         break;
 
       case 15:
         // Prompt (cancel, with checkbox)
         state = {
             msg   : "This is the prompt text.",
             title : "TestTitle",
             iconClass   : "question-icon",
@@ -397,22 +464,21 @@ function handleDialog(ui, testNum) {
             checkHidden : false,
             textValue   : "tribbles",
             passValue   : "",
             checkMsg    : "Check me out!",
             checked     : false,
             focused     : ui.loginTextbox.inputField,
             defButton   : ui.button0,
         };
-        checkExpectedState(ui, state);
-
-        clickOK = false;
-        // XXX dumb. old code driven by oncommand.
-        checkbox.setChecked(true);
-        checkbox.doCommand();
+        action = {
+            buttonClick: "cancel",
+            setCheckbox: true,
+        };
+        checkExpectedState(ui, state, action);
         break;
 
       case 16:
         // PromptUsernameAndPassword (ok, with checkbox)
         state = {
             msg   : "This is the pUAP text.",
             title : "TestTitle",
             iconClass   : "authentication-icon question-icon",
@@ -421,23 +487,23 @@ function handleDialog(ui, testNum) {
             checkHidden : false,
             textValue   : "usr",
             passValue   : "ssh",
             checkMsg    : "Check me out!",
             checked     : false,
             focused     : ui.loginTextbox.inputField,
             defButton   : ui.button0,
         };
-        checkExpectedState(ui, state);
-
-        textField.setAttribute("value", "newusr");
-        passField.setAttribute("value", "newssh");
-        // XXX dumb. old code driven by oncommand.
-        checkbox.setChecked(true);
-        checkbox.doCommand();
+        action = {
+            buttonClick: "ok",
+            setCheckbox: true,
+            textField: "newusr",
+            passField: "newssh",
+        };
+        checkExpectedState(ui, state, action);
         break;
 
       case 17:
         // PromptUsernameAndPassword (cancel, with checkbox)
         state = {
             msg   : "This is the pUAP text.",
             title : "TestTitle",
             iconClass   : "authentication-icon question-icon",
@@ -446,25 +512,23 @@ function handleDialog(ui, testNum) {
             checkHidden : false,
             textValue   : "usr",
             passValue   : "ssh",
             checkMsg    : "Check me out!",
             checked     : false,
             focused     : ui.loginTextbox.inputField,
             defButton   : ui.button0,
         };
-        checkExpectedState(ui, state);
-
-        textField.setAttribute("value", "newusr");
-        passField.setAttribute("value", "newssh");
-        // XXX dumb. old code driven by oncommand.
-        checkbox.setChecked(true);
-        checkbox.doCommand();
-
-        clickOK = false;
+        action = {
+            buttonClick : "cancel",
+            setCheckbox : true,
+            textField   : "newusr",
+            passField   : "newssh",
+        };
+        checkExpectedState(ui, state, action);
         break;
 
       case 18:
         // PromptPassword (ok, with checkbox)
         state = {
             msg   : "This is the promptPassword text.",
             title : "TestTitle",
             iconClass   : "authentication-icon question-icon",
@@ -473,22 +537,22 @@ function handleDialog(ui, testNum) {
             checkHidden : false,
             textValue   : "",
             passValue   : "ssh",
             checkMsg    : "Check me out!",
             checked     : false,
             focused     : ui.password1Textbox.inputField,
             defButton   : ui.button0,
         };
-        checkExpectedState(ui, state);
-
-        passField.setAttribute("value", "newssh");
-        // XXX dumb. old code driven by oncommand.
-        checkbox.setChecked(true);
-        checkbox.doCommand();
+        action = {
+            buttonClick : "ok",
+            setCheckbox : true,
+            passField   : "newssh",
+        };
+        checkExpectedState(ui, state, action);
         break;
 
       case 19:
         // PromptPassword (cancel, with checkbox)
         state = {
             msg   : "This is the promptPassword text.",
             title : "TestTitle",
             iconClass   : "authentication-icon question-icon",
@@ -497,24 +561,22 @@ function handleDialog(ui, testNum) {
             checkHidden : false,
             textValue   : "",
             passValue   : "ssh",
             checkMsg    : "Check me out!",
             checked     : false,
             focused     : ui.password1Textbox.inputField,
             defButton   : ui.button0,
         };
-        checkExpectedState(ui, state);
-
-        passField.setAttribute("value", "newssh");
-        // XXX dumb. old code driven by oncommand.
-        checkbox.setChecked(true);
-        checkbox.doCommand();
-
-        clickOK = false;
+        action = {
+            buttonClick : "cancel",
+            setCheckbox : true,
+            passField   : "newssh",
+        };
+        checkExpectedState(ui, state, action);
         break;
 
       case 20:
         // ConfirmEx (ok/cancel, ok)
         state = {
             msg   : "This is the confirmEx text.",
             title : "TestTitle",
             iconClass   : "question-icon",
@@ -523,19 +585,22 @@ function handleDialog(ui, testNum) {
             checkHidden : true,
             textValue   : "",
             passValue   : "",
             checkMsg    : "",
             checked     : false,
             focused     : ui.button0,
             defButton   : ui.button0,
         };
+        action = {
+            buttonClick: "ok",
+        };
         is(ui.button0.label, "OK",     "Checking accept-button label");
         is(ui.button1.label, "Cancel", "Checking cancel-button label");
-        checkExpectedState(ui, state);
+        checkExpectedState(ui, state, action);
         break;
 
       case 21:
         // ConfirmEx (yes/no, cancel)
         state = {
             msg   : "This is the confirmEx text.",
             title : "TestTitle",
             iconClass   : "question-icon",
@@ -544,20 +609,22 @@ function handleDialog(ui, testNum) {
             checkHidden : true,
             textValue   : "",
             passValue   : "",
             checkMsg    : "",
             checked     : false,
             focused     : ui.button0,
             defButton   : ui.button0,
         };
+        action = {
+            buttonClick: "cancel",
+        };
         is(ui.button0.label, "Yes", "Checking accept-button label");
         is(ui.button1.label, "No",  "Checking cancel-button label");
-        checkExpectedState(ui, state);
-        clickOK = false;
+        checkExpectedState(ui, state, action);
         break;
 
       case 22:
         // ConfirmEx (buttons from args, checkbox, ok)
         state = {
             msg   : "This is the confirmEx text.",
             title : "TestTitle",
             iconClass   : "question-icon",
@@ -566,24 +633,24 @@ function handleDialog(ui, testNum) {
             checkHidden : false,
             textValue   : "",
             passValue   : "",
             checkMsg    : "Check me out!",
             checked     : false,
             focused     : ui.button0,
             defButton   : ui.button0,
         };
+        action = {
+            buttonClick: "ok",
+            setCheckbox: true,
+        };
         is(ui.button0.label, "butt0", "Checking accept-button label");
         is(ui.button1.label, "butt1", "Checking cancel-button label");
         is(ui.button2.label, "butt2", "Checking extra1-button label");
-        checkExpectedState(ui, state);
-
-        // XXX dumb. old code driven by oncommand.
-        checkbox.setChecked(true);
-        checkbox.doCommand();
+        checkExpectedState(ui, state, action);
         break;
 
       case 23:
         // ConfirmEx (buttons from args, checkbox, cancel)
         state = {
             msg   : "This is the confirmEx text.",
             title : "TestTitle",
             iconClass   : "question-icon",
@@ -592,27 +659,25 @@ function handleDialog(ui, testNum) {
             checkHidden : false,
             textValue   : "",
             passValue   : "",
             checkMsg    : "Check me out!",
             checked     : false,
             focused     : ui.button1, // Default changed!
             defButton   : ui.button1,
         };
+        action = {
+            buttonClick: "cancel",
+            setCheckbox: true,
+        };
         // XXX check button1 is default
         is(ui.button0.label, "butt0", "Checking accept-button label");
         is(ui.button1.label, "butt1", "Checking cancel-button label");
         is(ui.button2.label, "butt2", "Checking extra1-button label");
-        checkExpectedState(ui, state);
-
-        // XXX dumb. old code driven by oncommand.
-        checkbox.setChecked(true);
-        checkbox.doCommand();
-
-        clickOK = false;
+        checkExpectedState(ui, state, action);
         break;
 
       case 24:
         // ConfirmEx (buttons from args, checkbox, button3)
         state = {
             msg   : "This is the confirmEx text.",
             title : "TestTitle",
             iconClass   : "question-icon",
@@ -621,28 +686,25 @@ function handleDialog(ui, testNum) {
             checkHidden : false,
             textValue   : "",
             passValue   : "",
             checkMsg    : "Check me out!",
             checked     : false,
             focused     : ui.button2, // Default changed!
             defButton   : ui.button2,
         };
+        action = {
+            buttonClick: 2,
+            setCheckbox: true,
+        };
         // XXX check button2 is default
         is(ui.button0.label, "butt0", "Checking accept-button label");
         is(ui.button1.label, "butt1", "Checking cancel-button label");
         is(ui.button2.label, "butt2", "Checking extra1-button label");
-        checkExpectedState(ui, state);
-
-        // XXX dumb. old code driven by oncommand.
-        checkbox.setChecked(true);
-        checkbox.doCommand();
-
-        // XXX how to click button 3?
-        clickOK = false;
+        checkExpectedState(ui, state, action);
         break;
 
       case 25:
         // Alert, null window
         state = {
             msg   : "This is the alert text.",
             title : "TestTitle",
             iconClass   : "alert-icon",
@@ -651,17 +713,20 @@ function handleDialog(ui, testNum) {
             checkHidden : true,
             textValue   : "",
             passValue   : "",
             checkMsg    : "",
             checked     : false,
             focused     : ui.button0,
             defButton   : ui.button0,
         };
-        checkExpectedState(ui, state);
+        action = {
+            buttonClick: "ok",
+        };
+        checkExpectedState(ui, state, action);
         break;
 
       case 26:
         // ConfirmEx (with delay, ok)
         state = {
             msg   : "This is the confirmEx delay text.",
             title : "TestTitle",
             iconClass   : "question-icon",
@@ -676,21 +741,25 @@ function handleDialog(ui, testNum) {
             defButton   : ui.button0,
         };
 
         // OS X doesn't initially focus the button, but rather the infoBody.
         // The focus stays there even after the button-enable delay has fired.
         if (isOSX)
             state.focused = ui.infoBody;
 
+        action = {
+            buttonClick: "pollOK",
+        };
+
         is(ui.button0.label, "OK",     "Checking accept-button label");
         is(ui.button1.label, "Cancel", "Checking cancel-button label");
         is(ui.button0.disabled, true,  "Checking accept-button is disabled");
         is(ui.button1.disabled, false, "Checking cancel-button isn't disabled ");
-        checkExpectedState(ui, state);
+        checkExpectedState(ui, state, action);
         break;
 
 
       case 100:
         // PromptAuth (no realm, ok, with checkbox)
         state = {
             msg : 'Enter username and password for http://example.com',
             title : "TestTitle",
@@ -700,23 +769,23 @@ function handleDialog(ui, testNum) {
             checkHidden : false,
             textValue   : "",
             passValue   : "",
             checkMsg    : "Check me out!",
             checked     : false,
             focused     : ui.loginTextbox.inputField,
             defButton   : ui.button0,
         };
-        checkExpectedState(ui, state);
-
-        textField.setAttribute("value", "username");
-        passField.setAttribute("value", "password");
-        // XXX dumb. old code driven by oncommand.
-        checkbox.setChecked(true);
-        checkbox.doCommand();
+        action = {
+            buttonClick : "ok",
+            setCheckbox : true,
+            textField   : "username",
+            passField   : "password",
+        };
+        checkExpectedState(ui, state, action);
         break;
 
       case 101:
         // PromptAuth (long realm, ok, with checkbox)
         state = {
             msg : 'A username and password are being requested by http://example.com. The site '  +
                   'says: "abcdefghi abcdefghi abcdefghi abcdefghi abcdefghi abcdefghi abcdefghi ' +
                   'abcdefghi abcdefghi abcdefghi abcdefghi abcdefghi abcdefghi abcdefghi '        +
@@ -728,51 +797,31 @@ function handleDialog(ui, testNum) {
             checkHidden : false,
             textValue   : "",
             passValue   : "",
             checkMsg    : "Check me out!",
             checked     : false,
             focused     : ui.loginTextbox.inputField,
             defButton   : ui.button0,
         };
-        checkExpectedState(ui, state);
-
-        textField.setAttribute("value", "username");
-        passField.setAttribute("value", "password");
-        // XXX dumb. old code driven by oncommand.
-        checkbox.setChecked(true);
-        checkbox.doCommand();
+        action = {
+            buttonClick : "ok",
+            setCheckbox : true,
+            textField   : "username",
+            passField   : "password",
+        };
+        checkExpectedState(ui, state, action);
         break;
 
       default:
         ok(false, "Uhh, unhandled switch for testNum #" + testNum);
         break;
     }
 
-    if (testNum == 24) {
-        ui.button2.click();
-    } else if (testNum == 26) {
-        // Buttons are disabled at the moment, poll until they're reenabled.
-        // Can't use setInterval here, because the window's in a modal state
-        // and thus DOM events are suppressed.
-        pollTimer = Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer);
-        pollTimer.initWithCallback(SpecialPowers.wrapCallback(function() {
-          pollDialog(ui.button0);
-        }),
-                                   100, Ci.nsITimer.TYPE_REPEATING_SLACK);
-        return;
-    } else {
-        if (clickOK)
-            ui.button0.click();
-        else
-            ui.button1.click();
-    }
-
     ok(true, "handleDialog done");
-    didDialog = true;
 }
 
 
 function* runTests() {
     let ioService = Cc["@mozilla.org/network/io-service;1"].
                     getService(Ci.nsIIOService);
     ok(true, "Running tests (isTabModal=" + isTabModal + ", usePromptService=" + usePromptService + ")");
 

--- a/toolkit/components/prompts/test/test_modal_select.html
+++ b/toolkit/components/prompts/test/test_modal_select.html
@@ -14,128 +14,127 @@ Prompter tests: modal prompts
   <iframe id="iframe"></iframe>
 </div>
 
 <pre id="test">
 <script class="testbody" type="text/javascript;version=1.8">
 
 let prompter = Cc["@mozilla.org/embedcomp/prompt-service;1"].
                getService(Ci.nsIPromptService2);
-let ioService = Cc["@mozilla.org/network/io-service;1"].
-                getService(Ci.nsIIOService);
-let pollTimer;
 
-function pollDialog(dialog) {
-    if (dialog.getButton("accept").disabled)
-        return;
-
-    ok(true, "dialog button is enabled now");
-    pollTimer.cancel();
-    pollTimer = null;
-    dialog.acceptDialog();
-    didDialog = true;
-}
-
-function checkExpectedSelectState(doc, state) {
+function checkExpectedSelectState(doc, state, action) {
     let msg = doc.getElementById("info.txt").value;
     // XXX check title? OS X has title in content
+    let dialog = doc.getElementsByTagName("dialog")[0];
     let listbox = doc.getElementById("list");
 
     is(msg, state.msg, "Checking expected message");
     // XXX check title? OS X has title in content
     // Compare listbox contents
     let count = listbox.itemCount;
     is(count, state.items.length, "Checking listbox length");
     if (count)
         is(listbox.selectedIndex, 0, "Checking selected index");
 
     for (let i = 0; i < count; i++) {
         let item = listbox.getItemAtIndex(i).label;
         is(item, items[i], "Checking item #" + i + " label");
     }
+
+    /* Actions */
+
+    if (action.selectItem) {
+        listbox.selectedIndex = 1;
+    }
+
+    if (action.buttonClick == "ok") {
+        dialog.acceptDialog();
+    } else if (action.buttonClick == "cancel") {
+        dialog.cancelDialog();
+    }
+
+    didDialog = true;
 }
 
 /*
  * handleDialog
  *
  * Invoked a short period of time after calling startCallbackTimer(), and
  * allows testing the actual prompt dialog while it's being displayed. Tests
  * should call startCallbackTimer() each time the auth dialog is expected (the
  * timer is a one-shot).
  */
 function handleDialog(doc, testNum) {
     ok(true, "--- handleDialog for test " + testNum + " ---");
 
-    let dialog    = doc.getElementsByTagName("dialog")[0];
-    let listbox   = doc.getElementById("list");
-    let clickOK   = true;
-    let state;
+    let state, action;
 
     // XXX check focused element
-    // XXX check text/passbox labels?
     // XXX check button labels?
 
     switch(testNum) {
       case 1:
         // Select (0 items)
         state = {
             msg   : "This is the select text.",
             title : "TestTitle",
             items : [],
         };
-        checkExpectedSelectState(doc, state);
+        action = {
+            buttonClick: "ok",
+        };
+        checkExpectedSelectState(doc, state, action);
         break;
 
       case 2:
         // Select (3 items, default ok)
         state = {
             msg   : "This is the select text.",
             title : "TestTitle",
             items : ["one", "two", "three"],
         };
-        checkExpectedSelectState(doc, state);
+        action = {
+            buttonClick: "ok",
+        };
+        checkExpectedSelectState(doc, state, action);
         break;
 
       case 3:
         // Select (3 items, change selection, ok)
         state = {
             msg   : "This is the select text.",
             title : "TestTitle",
             items : ["one", "two", "three"],
         };
-        checkExpectedSelectState(doc, state);
-        // XXX need to trigger old code's click listener
-        listbox.selectedIndex = 1;
-        //listbox.getItemAtIndex(1).click();
+        action = {
+            buttonClick: "ok",
+            selectItem: 1,
+        };
+        checkExpectedSelectState(doc, state, action);
         break;
 
       case 4:
         // Select (3 items, cancel)
         state = {
             msg   : "This is the select text.",
             title : "TestTitle",
             items : ["one", "two", "three"],
         };
-        checkExpectedSelectState(doc, state);
-        clickOK = false;
+        action = {
+            buttonClick: "cancel",
+        };
+        checkExpectedSelectState(doc, state, action);
         break;
 
       default:
         ok(false, "Uhh, unhandled switch for testNum #" + testNum);
         break;
     }
 
-
-    if (clickOK)
-        dialog.acceptDialog();
-    else
-        dialog.cancelDialog();
-
     ok(true, "handleDialog done");
-    didDialog = true;
 }
 
 let testNum   = 0;
 let selectVal = {};
 let isOK;
 
 isSelectDialog = true;
 isTabModal = false;