Need Help with a test class to my apex class that attaches a Visualforce Page pdf to the quote [duplicate]

Question

I found a way to write an apex class that attaches my quote which is generated by an vf page as a pdf to my quote object.

Writing the test class is even a bigger problem for me. I get to 36% coverage and hop you guys can help me with it to get it working.

here's my class

    public class quotePDFExtension {
    ApexPages.StandardController controller;
    public Quote quote {get;set;}
    public PageReference rtn;
    public quotePDFExtension(ApexPages.StandardController c){
        quote = (Quote)c.getRecord();
        rtn = c.view();
    }
    public PageReference attachQuotePDF() {
        /* Get the page definition */
        PageReference pdfPage = Page.angebot;
        pdfPage.getParameters().put('id',quote.id);
        /* generate the pdf blob */
        Blob pdfBlob = pdfPage.getContent();
        /* create the attachment against the offer */
        Attachment a = new Attachment(parentId = quote.id, name=quote.Angebot_Nr__c + '.pdf', body = pdfBlob);
        /* insert the attachment */
        insert a;
        /* send the user back to the offer detail page */
        return rtn;
    }


}

and here is my test class

    @isTest 
public class attachQuoteTestClass 
{
 static testMethod void testMethod1() 
 {
 Quote testQuote = new Quote(OpportunityId = '0061x00000AN92q', Gutachtennummer__c = '999195041551', Gutachten_Datum__c = Date.today(), Angebotsdatum__c = Date.today());
 testQuote.Name='Test Quote record' ;
 insert testQuote;

/* 
 Attachment attach = new Attachment();
 attach.Name='Unit Test Attachment';

 Blob bodyBlob = Blob.valueOf('Unit Test Attachment Body');
 attach.body=bodyBlob;
 attach.parentId = testQuote.Id;
 insert attach;

 List<Attachment> attachments=[select id, name from Attachment where parent.id=:testQuote.id];
 System.assertEquals(1, attachments.size());

 ApexPages.StandardController sc = new ApexPages.StandardController(testQuote);
 quotePDFExtension ctr = new quotePDFExtension(sc);
*/

 Test.StartTest(); 
  ApexPages.StandardController sc = new ApexPages.StandardController(testQuote);
  quotePDFExtension testQuotePlan = new quotePDFExtension(sc);

  PageReference pageRef = Page.angebot;
  pageRef.getParameters().put('id', String.valueOf(testQuote.Id));
  Test.setCurrentPage(pageRef);

  Blob b = blob.valueof('error');
  Try { b = pageRef.getContent();}
  Catch(Exception e)
  {Attachment a = new Attachment(parentId = testQuote.id, name=testQuote.Angebot_Nr__c + '.pdf', body = b);
  insert a;}

 Test.StopTest();
 }
}

Thanks a lot Thomas