mysql: Client.prototype.format shouldn't treat "?" as placeholder inside string literals

Description

Client.prototype.format attempts to replace every occurrence of ? for a variable. Even if it’s inside a string literal.

E.g.:

 mysql.query("SELECT * FROM ponies WHERE emotion = 'wtf?' AND id = ?", [1]) 

results in error because function expects two parameters instead of one.

Solutions

Option 1

Pretend it’s a feature 😃 And do adhoc stuff like this:

 mysql.query("SELECT * FROM ponies WHERE emotion = 'wtf?' AND id = ?", ['?', 1]) 

Option 2

Placeholders should be left intact if in string literals. Such behavior can be observed in PHP PDO

mysql.query("SELECT * FROM ponies WHERE emotion = 'wtf?' AND id = ?", [1]) 
    // SELECT * FROM ponies WHERE emotion = 'wtf?' AND id = 1

Option 3

Add escaping convention for ?.

For example, use # or \ and do something like:

?      => value
#?     => ?
##     => #
###?   => #?

IMHO, we should stay away from \ as it can easily turn into escaping hell like in these non-real-world examples:

// SELECT * FROM ponies WHERE emotion = 'wtf?' AND id = ?
mysql.query('SELECT * FROM ponies WHERE emotion = \'wtf\\?\' AND id = ?', [1]) 

// SELECT * FROM ninjas WHERE slash_and_question = '\\?' AND id = ?'
// has to be: SELECT * FROM ninjas WHERE slash_and_question = '\\\\\?' AND id = ?'
mysql.query('SELECT * FROM ninjas WHERE slash_and_question = \'\\\\\\\\\\?\' AND id = ?', [1]) 

I have patch for options 1 and 2. Option 3 is a piece of cake. Which one should I attach? 😃