ReRender function is not working in lightning component

Question

I have below LDS Component, at the console log, I can see render and after render log but once I start typing in one of the input fields, I get nothing from rerender log. can someone please help me to get the log from rerender function?

<aura:component implements="force:appHostable,flexipage:availableForAllPageTypes" >
    <aura:attribute name="recordId" type="String" />

        <lightning:card iconName="action:add_contact" title="Add Contact">
            <div class="slds-p-around_small">
            <lightning:recordEditForm 
                                      objectApiName="Contact"
                                      onsuccess="{!c.handleSuccess}">
                <lightning:messages />

                <lightning:inputField fieldName="Name" />
                <lightning:inputField fieldname="Languages__c" />
                <lightning:inputField fieldName="Birthdate" />
                <lightning:inputField fieldName="Phone" />
                <lightning:inputField fieldName="Email" />
                <lightning:inputField fieldName="LeadSource" />
                <lightning:inputField fieldName="Level__c" />
                <lightning:inputField fieldName="CleanStatus" />
                <lightning:button aura:id="submit" type="submit" label="Save" class="slds-m-top_medium" />
                <lightning:button aura:id="cancel" type="cancel" label="cancel" class="slds-m-top_medium" />
            </lightning:recordEditForm>
            <lightning:navigation aura:id="navService"/>
            </div>
        </lightning:card>   
</aura:component>

and below Renderer

({
    render : function (component, event, helper) {

    var act = this.superRender();

    console.log("This is from render function.");

    return act;
},
afterRender : function (component, event, helper) {

    var act = this.superAfterRender();

    console.log("This is from after render function.");
    //console.log("This is again from after render function.");       
},

rerender : function (component, event, helper) {

    var act = this.superRerender();

    console.log("This is from reRender function.");
    //console.log("This is again from reRender function.");       
},

unrender : function (component, event, helper) {

    var act = this.superUnrender();

    console.log("This is from unRender function.");
    console.log("This is again from unRender function.");       
} 

})

and just to avoid the X Y problem I am creating a contact with the LDS but I want a little addition to this, the exact scenario is once I type the name I want a function to fetch the value I have typed in a name without even hitting any buttons and then that value would be compared in the SOQL and if any duplicate contact matched then it will iterate the possible duplicate value(I haven't mentioned the iteration code yet), if I say the same thing in different words I am creating a contact and before hitting the save button I want to check whether this contact already exists in the database or not.

Answer 1

Simply typing into a field by itself won't cause a rerender event. What needs to happen is at least one aura:valueChange event needs to fire, at which point the system will determine if a rerender needs to occur. Here's a demonstration of rerendering:

<aura:application >
    <aura:attribute name="rows" type="List" default="[]" />
    <aura:iteration items="{!v.rows}" var="item">
        <div>{!item}</div>
    </aura:iteration>
    <lightning:button label="Add" onclick="{!c.addrow}" />
</aura:application>

---

({
    addrow: function(component, event, helper) {
        let rows = component.get("v.rows");
        rows.push(rows.length);
        component.set("v.rows", rows);

    }
})

---

({
    rerender: function(component, event, helper) {
        var result = this.superRerender();
        console.log("rerender event fires");
        return result;
    }
})