Rule Request: imports_at_top

New Issue Checklist

• Updated SwiftLint to the latest version
• I searched for existing GitHub issues

New Rule Request

Suggested name: imports_at_top

Require file-scope import declarations to appear at the beginning of the source file (after an optional file header / comments), not after types or other declarations.

Swift treats imports as file-scoped regardless of where they are written, so this compiles:

import Testing

struct Example {}

@testable import MyModule

sorted_imports does not catch it. As of 0.62.0 it only sorts a contiguous import block; an import after other code is a separate one-line group, so lint and --fix leave it at the bottom. I could not find an existing issue that asks for this placement check (nearby work is sort order inside a block: #4810, #6665, #4935).

Why

This is the usual Swift convention. Google’s Swift style guide says import statements are the first non-comment tokens in a source file.

Apple’s swift-format already enforces it. OrderedImports:

Lint: If an import appears anywhere other than the beginning of the file it resides in, not lexicographically ordered, or (optionally) not in the appropriate import group, a lint error is raised.

Format: Imports will be reordered and (optionally) grouped at the top of the file.

A dedicated SwiftLint rule (or a sorted_imports option) would close the same gap for projects that use SwiftLint rather than swift-format. I am filing a matching request on nicklockwood/SwiftFormat.

Triggering

import Foundation

struct Foo {}

import UIKit // violation

import Testing

struct FooTests {}

@testable import MyModule // violation

Non-triggering

// File header comment is fine.

import Foundation
import UIKit

struct Foo {}

#if canImport(UIKit)
import UIKit
#endif
import Foundation

struct Foo {}

(Header #if import groups that sit with the leading imports should stay allowed.)

Configuration

Optional, if useful:

• whether to allow #if / #endif import groups only when they are part of the leading import section
• whether comments between the file header and the first import are allowed (yes by default)

Sorting within the header block can remain sorted_imports. This rule only needs to flag (and ideally correct) imports that are not in that leading section.

Opt-in

Opt-in. Placement is a style convention, not a correctness issue, and some codebases may put #if imports later on purpose. That matches the README guidance for rules that are not general consensus. Correction (hoist to the header, then let sorted_imports order them) would be useful.

Start by examining the existing sorted_imports rule and how SwiftLint handles import groups and opt-in rules. The work is done when imports after declarations are reported and, if correction is supported, moved into the leading import section while header comments and leading conditional import groups remain allowed.