/**

* @name Names only differing by case

* @description Names only differing by case can cause confusion.

* @kind problem

* @problem.severity warning

* @id ql/names-only-differing-by-case

* @tags correctness

* maintainability

* @precision high

*/

import ql

import codeql_ql.style.AcronymsShouldBeCamelCaseQuery as Acronyms

private import codeql_ql.style.NodeName as NodeName

string getName(AstNode node, string kind, YAML::QLPack pack) {

result = NodeName::getName(node, kind) and

node.getLocation().getFile() = pack.getAFileInPack() and

not node.hasAnnotation("deprecated") and // deprecated nodes are not interesting

not node.getLocation().getFile().getBaseName() = "TreeSitter.qll" and // auto-generated, is sometimes bad.

not node.getLocation().getFile().getExtension() = "ql" // .ql files cannot be imported, so no risk of conflict

}

// get better join-order by getting all the relevant information in a single utility predicate

pragma[nomagic]

string getNameAndPack(AstNode node, string kind, string lower, YAML::QLPack pack) {

result = getName(node, kind, pack) and lower = result.toLowerCase()

}

predicate problem(string name1, AstNode node1, string name2, string kind) {

exists(string lower, YAML::QLPack pack1, YAML::QLPack pack2 |

name1 = getNameAndPack(node1, kind, lower, pack1) and

name1.length() >= 2 and

pack2 = pack1.getADependency*() and

name2 = getNameAndPack(_, kind, lower, pack2) and // TODO: Get if it's a dependency pack in the alert-message.

name1 != name2 and

kind != "variable" // these are benign, and plentiful...

)

}

string prettyPluralKind(string kind) {

kind = "class" and result = "classes"

or

kind = "classlessPredicate" and result = "predicates"

or

kind = "classPredicate" and result = "class predicates"

or

kind = "newtypeBranch" and result = "newtype branches"

or

kind = "newtype" and result = "newtypes"

or

kind = "variable" and result = "variables"

or

kind = "field" and result = "fields"

or

kind = "module" and result = "modules"

}

from string name1, AstNode node, string name2, string kind

where problem(name1, node, name2, kind) and not name1.toLowerCase() = "geturl"

select node,

name1 + " is only different by casing from " + name2 + " that is used elsewhere for " +

prettyPluralKind(kind) + "."