indentation_width warning when preprocessor statements are used

[phranck]

New Issue Checklist

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

Describe the bug

With enabled rule indentation_width you will get warnings for preprocessor statements in nested structures. Xcode's cmd + i formats the code correctly (preprocessor statements always at the beginning of a line, all other commands, view modifiers etc. indented as expected.

Code Snippet

private struct MyView: View {
#if os(iOS)
    @State var scrollViewHeight: CGFloat = .zero
#endif
    @EnvironmentObject var config: MyConfig

    var body: some View {
#if os(iOS)
        ScrollView {                          // <- This triggers warning
            content
        }
        .frame(maxHeight: scrollViewHeight)
#else
        content                               // <- This triggers warning
#endif
    }
}

Complete output when running SwiftLint, including the stack trace and command used

$ swiftlint lint

Warning Output

Indentation Width Violation: Code should be indented using one tab or 4 spaces. (indentation_width)

Environment

• SwiftLint version (run swiftlint version to be sure)? - 0.47.1
• Installation method used (Homebrew, CocoaPods, building from source, etc)? - SPM Build Tool Plugin
• Paste your configuration file:

excluded:

disabled_rules:
  - identifier_name
  - notification_center_detachment
  - orphaned_doc_comment
  - statement_position
  - todo
  - unused_capture_list

opt_in_rules:
  - array_init
  - attributes
  - closure_end_indentation
  - closure_spacing
  - collection_alignment
  - colon
  - convenience_type
  - discarded_notification_center_observer
  - discouraged_object_literal
  - empty_collection_literal
  - empty_count
  - empty_string
  - enum_case_associated_values_count
  - explicit_init
  - fatal_error_message
  - first_where
  - force_unwrapping
  - identical_operands
  - implicitly_unwrapped_optional
  - indentation_width
  - last_where
  - leading_whitespace
  - legacy_random
  - literal_expression_end_indentation
  - modifier_order
  - multiline_arguments
  - multiline_function_chains
  - multiline_literal_brackets
  - multiline_parameters
  - multiline_parameters_brackets
  - number_separator
  - operator_usage_whitespace
  - pattern_matching_keywords
  - prefer_self_type_over_type_of_self
  - redundant_nil_coalescing
  - redundant_type_annotation
  - required_deinit
  - sorted_imports
  - static_operator
  - strict_fileprivate
  - switch_case_alignment
  - switch_case_on_newline
  - toggle_bool
  - trailing_closure
  - unavailable_function
  - unneeded_parentheses_in_closure_argument
  - vertical_whitespace_closing_braces
  - vertical_whitespace_opening_braces
  - yoda_condition


analyzer_rules:
  - unused_declaration
  - unused_import


custom_rules:
  array_constructor:
    name: "Array/Dictionary initializer"
    regex: '[let,var] .+ = (\[.+\]\(\))'
    capture_group: 1
    message: "Use explicit type annotation when initializing empty arrays and dictionaries"
    severity: warning


force_cast: warning
force_try: warning
function_body_length:
    warning: 60

legacy_hashing: error

identifier_name:
  excluded:
    - i
    - id
    - x
    - y
    - z

line_length:
  warning: 140
  error: 240
  ignores_urls: true
  ignores_function_declarations: true
  ignores_comments: true

multiline_arguments:
  first_argument_location: next_line
  only_enforce_after_first_closure_on_first_line: true

private_over_fileprivate:
  validate_extensions: true

trailing_whitespace:
  ignores_empty_lines: false
  ignores_comments: true

vertical_whitespace:
  max_empty_lines: 1

reporter: "xcode"

• Are you using nested configurations? - NO
• Which Xcode version are you using (check xcodebuild -version)?

Xcode 14.0
Build version 14A5270f

• Do you have a sample that shows the issue? - see example above

[SimplyDanny]

There is now a new option include_compiler_directives you can set to false. This is supposed to silence the warnings in your example.

[phranck]

Thanks @SimplyDanny! You are right, it works for something like in my example.
Unfortunately it doesn't work for something like this (maybe for extensions):

public extension Font {
    static var cuLargeTitle: Font {
#if os(iOS)
        Font.system(size: UIFontMetrics.default.scaledValue(for: 32), weight: .heavy)   // triggers warning
#elseif os(macOS)
        Font.system(size: 26, weight: .bold)   // triggers warning
#endif
    }

    static var cuTitle: Font {
#if os(iOS)
        Font.system(size: UIFontMetrics.default.scaledValue(for: 26), weight: .bold)   // triggers warning
#elseif os(macOS)
        Font.system(size: 22, weight: .semibold)   // triggers warning
#endif
    }

…
}