ExpectedMappingForFormatString.ql

/**
 * @name Formatted object is not a mapping
 * @description The formatted object must be a mapping when the format includes a named specifier; otherwise a TypeError will be raised."
 * @kind problem
 * @tags reliability
 *       correctness
 * @problem.severity error
 * @sub-severity low
 * @precision high
 * @id py/percent-format/not-mapping
 */

import python
import semmle.python.strings

/* modernized query
from Expr e, ClassValue t
where exists(BinaryExpr b | b.getOp() instanceof Mod and format_string(b.getLeft()) and e = b.getRight() and
mapping_format(b.getLeft()) and e.pointsTo(_, t, _) and not t.isMapping())
select e, "Right hand side of a % operator must be a mapping, not class $@.", t, t.getName()
//*/

/* original query
from Expr e, ClassObject t
where exists(BinaryExpr b | b.getOp() instanceof Mod and format_string(b.getLeft()) and e = b.getRight() and
mapping_format(b.getLeft()) and e.refersTo(_, t, _) and not t.isMapping())
select e, "Right hand side of a % operator must be a mapping, not class $@.", t, t.getName()
//*/

//* debug query
from Expr e, ClassValue t, string s
where any()
  and exists(BinaryExpr b | any()
        and b.getOp() instanceof Mod
        and format_string(b.getLeft())
        and e = b.getRight()
        and mapping_format(b.getLeft())
        and e.pointsTo().getClass() = t
        //and not t.isMapping()
        )
  and if t.hasAttribute("__getitem__") then s = "yes" else s = "no"
select
    e
  , "Right hand side of a % operator must be a mapping, not class $@."
  , t
  , t.getName()
  , s
  , s
//*/