MdSelect hangs browser if FormControl does not exist

Bug, feature request, or proposal:

Bug

What is the expected behavior?

No values populated in the select control, or exception thrown

What is the current behavior?

Hangs the browser (Chrome and Safari at least, Edge/FF not tested)

What are the steps to reproduce?

set formControlName to the name of a control that doesn’t exist on the formGroup, i.e. if you accidentally left out a form control. If you’re using form.patchValue() to set the form controls it seems to prevent this issue if the control name is in the object passed to patchValue(), which might make the bug appear more random.

i.e.

        <md-select placeholder="Country" formControlName="Country">
            <md-option *ngFor="let country of countries" [value]="country.IsoCode">
                {{country.Name}}
            </md-option>
        </md-select>

where “Country” is not the name of a FormControl on the current FormGroup.

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What is the use-case or motivation for changing an existing behavior?

Which versions of Angular, Material, OS, browsers are affected?

Is there anything else we should know?

Seems to be an infinite loop running here:

    /**
     * Sets the select's value. Part of the ControlValueAccessor interface
     * required to integrate with Angular's core forms API.
     *
     * @param value New value to be written to the model.
     */
    MdSelect.prototype.writeValue = function (value) {
        var _this = this;
        if (!this.options) {
            // In reactive forms, writeValue() will be called synchronously before
            // the select's child options have been created. It's necessary to call
            // writeValue() again after the options have been created to ensure any
            // initial view value is set.
            Promise.resolve(null).then(function () { return _this.writeValue(value); });
            return;
        }
        this._setSelectionByValue(value);
    };

[aufdenpunkt]

Hi guys,

I got a similar issue when I try to render multiple md-options with an array of objects. The browser hangs when angular is trying to render the view.

This doesn’t work:

But this does:

Any ideas?

Thanks

[mrlund]

Could this be related to the rendering of options somehow?

By attaching the VS Code debugger and manually breaking, and then stepping through a couple of times, I was able to determine the browser was hanging because of an infinite loop, repeatedly hitting and satisfying the if (!this.options) condition quoted above, which just seems to call writeValue recursively until there’s options?