/**
 * @name Suspicious method name declaration
 * @description A method declaration with a name that is a special keyword in another
 * context is suspicious.
 * @kind problem
 * @problem.severity warning
 * @id js/suspicious-method-name-declaration
 * @precision high
 * @tags correctness
 * typescript
 * methods
 */

import javascript

/**
 * Holds if the method name on the given container is likely to be a mistake.
 */
predicate isSuspiciousMethodName(string name, ClassOrInterface container) {
 name = "function" and exists(container) // suspicious in any container
 or
 // "constructor" is only suspicious outside a class.
 name = "constructor" and not container instanceof ClassDefinition
 or
 // "new" is only suspicious inside a class.
 name = "new" and container instanceof ClassDefinition
}

from MethodDeclaration member, ClassOrInterface container, string name, string msg
where
 container.getLocation().getFile().getFileType().isTypeScript() and
 container.getMember(name) = member and
 isSuspiciousMethodName(name, container) and
 // Cases to ignore.
 not (
 // Assume that a "new" method is intentional if the class has an explicit constructor.
 name = "new" and
 container instanceof ClassDefinition and
 exists(ConstructorDeclaration constructor |
 container.getMember("constructor") = constructor and
 not constructor.isSynthetic()
 )
 or
 // Explicitly declared static methods are fine.
 container instanceof ClassDefinition and
 member.isStatic()
 or
 // Only looking for declared methods. Methods with a body are OK.
 exists(member.getBody().getBody())
 or
 // The developer was not confused about "function" when there are other methods in the interface.
 name = "function" and
 exists(MethodDeclaration other | other = container.getAMethod() |
 other.getName() != "function" and
 not other.(ConstructorDeclaration).isSynthetic()
 )
 ) and
 (
 name = "constructor" and
 msg =
 "The member name 'constructor' does not declare a constructor in interfaces, but it does in classes."
 or
 name = "new" and
 msg =
 "The member name 'new' does not declare a constructor, but 'constructor' does in class declarations."
 or
 name = "function" and
 msg =
 "The member name 'function' does not declare a function, it declares a method named 'function'."
 )
select member, msg