Javascript read "%%" both as "%" and "%%"?

Question

In writing a test I was comparing strings. And the test came back as Failing. I manually copy pasted the string and it works... Note the mysql string syntax; but it never touches mysql up to this point.

Console.logged copy+paste Both Strings look like this:

console.log(replaced);
"SELECT COUNT(*) FROM interaction WHERE ambassador_name LIKE '%' AND influencer_name = ?"

console.log(sqlQuery0);
"SELECT COUNT(*) FROM interaction WHERE ambassador_name LIKE '%' AND influencer_name = ?"

It Shouldn't be failing but it does. So I wanted to see where it fails:

it( "submits the proper first sql query", function(){
  var replaced = dao.SQLquery[0].replace(/  +/g, ' ');
  for (var i = 0; i < replaced.length; i++) {
    if (replaced[i] != sqlQuery0[i] ){
      console.log(replaced.slice(i-10,i+10));
      console.log(sqlQuery0.slice(i-10,i+10);
      break
    }
  }
})

TO My SUPRISE THE ABOVE RETURNED this..

me LIKE '%' AND inf
me LIKE '%' AND infl

They can't be different lengths.... right. I tried again.

  it( "submits the proper first sql query", function(){
    var replaced = dao.SQLquery[0].replace(/  +/g, ' ');
    for (var i = 0; i < replaced.length; i++) {
      if (replaced[i] != sqlQuery0[i] ){
        console.log('|'+ replaced.slice(i-10,i+10)+'|',replaced.slice(i-10,i+10).length);
        console.log('|'+sqlQuery0.slice(i-10,i+10)+'|',sqlQuery0.slice(i-10,i+10).length);
        break
      }
    }
  })

And to my bigger suprise:

|me LIKE '%' AND inf| 20
|me LIKE '%' AND infl| 20

But the First string is only length 19!

My last attampt:

var replaced = dao.SQLquery[0].replace(/  +/g, ' ');
for (var i = 0; i < replaced.length; i++) {
  console.log(replaced[i], sqlQuery0[i]);
  if (replaced[i] != sqlQuery0[i] ){
    console.log('|'+ replaced.slice(i-10,i+10)+'|',replaced.slice(i-10,i+10).length);
    console.log('|'+sqlQuery0.slice(i-10,i+10)+'|',sqlQuery0.slice(i-10,i+10).length);
    break
  }
}

gave me this:

n n
a a
m m
e e

L L
I I
K K
E E

' '
% %
% '
|me LIKE '%' AND inf| 20
|me LIKE '%' AND infl| 20

Apparently "%%" is interpreted as both % and %% how can this be ?

more:

var replaced = dao.SQLquery[0].replace(/  +/g, ' ');
console.log(sqlQuery0)
for (var i = 0; i < replaced.length; i++) {
  console.log(replaced[i], sqlQuery0[i]);
  if (replaced[i] != sqlQuery0[i] ){
    console.log('|'+ JSON.stringify(replaced.slice(i-10,i+10))+'|',replaced.slice(i-10,i+10).length);
    console.log('|'+ JSON.stringify(sqlQuery0.slice(i-10,i+10))+'|',sqlQuery0.slice(i-10,i+10).length);
    console.log('|'+ JSON.stringify(dao.SQLquery[0].slice(i-10,i+10))+'|',sqlQuery0.slice(i-10,i+10).length);
    break
  }
}

|"me LIKE '%' AND inf"| 20
|"me LIKE '%' AND infl"| 20
|"ame LIKE '%' AND in"| 20

Answer 1

expanding on what @Matt Ball and @blm said, you most likely have an 'invisible' character in the text that is in your 'replaced' variable. To test this, use a hex editor and paste the text from both the 'replaced' and sqlQuery0 variables in - you should be able to see that around the '%' character you have an invisible character like '00' NUL or '1E' record separator.

You can use this online Hex Viewer to test https://hexed.it/?hl=en

to see the ASCII codes I'm referring to, check out the ascii table http://www.asciitable.com/