mirror of
https://github.com/realm/SwiftLint.git
synced 2026-05-07 20:12:49 +00:00
Migrate TrailingWhitespaceRule from SourceKit to SwiftSyntax (#6117)
## Summary Convert TrailingWhitespaceRule to use SwiftSyntax instead of SourceKit for improved performance and better handling of trailing whitespace detection, especially within block comments. ## Key Technical Improvements - **Enhanced block comment detection** distinguishing between lines fully covered by block comments vs lines containing block comments with code - **Accurate whitespace detection** using CharacterSet.whitespaces for all Unicode whitespace characters, not just space and tab - **Improved comment handling** with proper detection of line-ending comments and multi-line block comment structures - **Better correction mechanism** using ViolationCorrection ranges instead of manual string reconstruction - **Line-based analysis** maintaining efficiency while providing precise violation positions ## Migration Details - Replaced `CorrectableRule` with `@SwiftSyntaxRule(correctable: true)` - Implemented `ViolationsSyntaxVisitor` pattern for line-based validation - Added `collectLinesFullyCoveredByBlockComments` to properly handle test framework comment wrapping scenarios - Distinguished between three comment scenarios: lines fully within block comments, full-line comments, and lines ending with comments - Maintained all configuration options (ignores_empty_lines, ignores_comments) - Preserved exact violation position reporting with UTF-8 offset calculations
This commit is contained in:
JP Simard
GitHub
@@ -35,6 +35,7 @@
|
||||
* `file_header`
|
||||
* `file_length`
|
||||
* `line_length`
|
||||
* `trailing_whitespace`
|
||||
* `vertical_whitespace`
|
||||
<!-- Keep empty line to have the contributors on a separate line. -->
|
||||
[JP Simard](https://github.com/jpsim)
|
||||
|
||||
@@ -1,7 +1,9 @@
|
||||
import Foundation
|
||||
import SourceKittenFramework
|
||||
import SwiftLintCore
|
||||
import SwiftSyntax
|
||||
|
||||
struct TrailingWhitespaceRule: CorrectableRule {
|
||||
@SwiftSyntaxRule(correctable: true)
|
||||
struct TrailingWhitespaceRule: Rule {
|
||||
var configuration = TrailingWhitespaceConfiguration()
|
||||
|
||||
static let description = RuleDescription(
|
||||
@@ -14,77 +16,314 @@ struct TrailingWhitespaceRule: CorrectableRule {
|
||||
Example("let name: String //\n"), Example("let name: String // \n"),
|
||||
],
|
||||
triggeringExamples: [
|
||||
Example("let name: String \n"), Example("/* */ let name: String \n")
|
||||
Example("let name: String↓ \n"), Example("/* */ let name: String↓ \n")
|
||||
],
|
||||
corrections: [
|
||||
Example("let name: String \n"): Example("let name: String\n"),
|
||||
Example("/* */ let name: String \n"): Example("/* */ let name: String\n"),
|
||||
Example("let name: String↓ \n"): Example("let name: String\n"),
|
||||
Example("/* */ let name: String↓ \n"): Example("/* */ let name: String\n"),
|
||||
]
|
||||
)
|
||||
}
|
||||
|
||||
func validate(file: SwiftLintFile) -> [StyleViolation] {
|
||||
let filteredLines = file.lines.filter {
|
||||
guard $0.content.hasTrailingWhitespace() else { return false }
|
||||
private extension TrailingWhitespaceRule {
|
||||
final class Visitor: ViolationsSyntaxVisitor<ConfigurationType> {
|
||||
// Pre-computed comment information for performance
|
||||
private var linesFullyCoveredByBlockComments = Set<Int>()
|
||||
private var linesEndingWithComment = Set<Int>()
|
||||
|
||||
let commentKinds = SyntaxKind.commentKinds
|
||||
if configuration.ignoresComments,
|
||||
let lastSyntaxKind = file.syntaxKindsByLines[$0.index].last,
|
||||
commentKinds.contains(lastSyntaxKind) {
|
||||
override func visit(_ node: SourceFileSyntax) -> SyntaxVisitorContinueKind {
|
||||
// Pre-compute all comment information in a single pass if needed
|
||||
if configuration.ignoresComments {
|
||||
precomputeCommentInformation(node)
|
||||
}
|
||||
|
||||
// Process each line for trailing whitespace violations
|
||||
for lineContents in file.lines {
|
||||
let line = lineContents.content
|
||||
let lineNumber = lineContents.index // 1-based
|
||||
|
||||
// Calculate trailing whitespace info
|
||||
guard let trailingWhitespaceInfo = line.trailingWhitespaceInfo() else {
|
||||
continue // No trailing whitespace
|
||||
}
|
||||
|
||||
// Apply `ignoresEmptyLines` configuration
|
||||
if configuration.ignoresEmptyLines &&
|
||||
line.trimmingCharacters(in: .whitespaces).isEmpty {
|
||||
continue
|
||||
}
|
||||
|
||||
// Apply `ignoresComments` configuration
|
||||
if configuration.ignoresComments {
|
||||
// Check if line is fully within a block comment
|
||||
if linesFullyCoveredByBlockComments.contains(lineNumber) {
|
||||
continue
|
||||
}
|
||||
|
||||
// Check if line ends with a comment (using pre-computed info)
|
||||
if linesEndingWithComment.contains(lineNumber) {
|
||||
continue
|
||||
}
|
||||
}
|
||||
|
||||
// Calculate violation position
|
||||
let lineStartPos = locationConverter.position(ofLine: lineNumber, column: 1)
|
||||
let violationStartOffset = line.utf8.count - trailingWhitespaceInfo.byteLength
|
||||
let violationPosition = lineStartPos.advanced(by: violationStartOffset)
|
||||
|
||||
let correctionEnd = lineStartPos.advanced(by: line.utf8.count)
|
||||
|
||||
violations.append(ReasonedRuleViolation(
|
||||
position: violationPosition,
|
||||
correction: .init(start: violationPosition, end: correctionEnd, replacement: "")
|
||||
))
|
||||
}
|
||||
return .skipChildren
|
||||
}
|
||||
|
||||
/// Pre-computes all comment information in a single pass for better performance
|
||||
private func precomputeCommentInformation(_ node: SourceFileSyntax) {
|
||||
// First, collect block comment information
|
||||
collectLinesFullyCoveredByBlockComments(node)
|
||||
|
||||
// Then, collect line comment ranges and determine which lines end with comments
|
||||
let lineCommentRanges = collectLineCommentRanges(from: node)
|
||||
determineLineEndingComments(using: lineCommentRanges)
|
||||
}
|
||||
|
||||
/// Collects ranges of line comments organized by line number
|
||||
private func collectLineCommentRanges(from node: SourceFileSyntax) -> [Int: [Range<AbsolutePosition>]] {
|
||||
var lineCommentRanges: [Int: [Range<AbsolutePosition>]] = [:]
|
||||
|
||||
for token in node.tokens(viewMode: .sourceAccurate) {
|
||||
// Process leading trivia
|
||||
var currentPos = token.position
|
||||
for piece in token.leadingTrivia {
|
||||
let pieceStart = currentPos
|
||||
currentPos += piece.sourceLength
|
||||
|
||||
if piece.isComment && !piece.isBlockComment {
|
||||
let pieceStartLine = locationConverter.location(for: pieceStart).line
|
||||
lineCommentRanges[pieceStartLine, default: []].append(pieceStart..<currentPos)
|
||||
}
|
||||
}
|
||||
|
||||
// Process trailing trivia
|
||||
currentPos = token.endPositionBeforeTrailingTrivia
|
||||
for piece in token.trailingTrivia {
|
||||
let pieceStart = currentPos
|
||||
currentPos += piece.sourceLength
|
||||
|
||||
if piece.isComment && !piece.isBlockComment {
|
||||
let pieceStartLine = locationConverter.location(for: pieceStart).line
|
||||
lineCommentRanges[pieceStartLine, default: []].append(pieceStart..<currentPos)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return lineCommentRanges
|
||||
}
|
||||
|
||||
/// Determines which lines end with comments based on line comment ranges
|
||||
private func determineLineEndingComments(using lineCommentRanges: [Int: [Range<AbsolutePosition>]]) {
|
||||
for lineNumber in 1...file.lines.count {
|
||||
let line = file.lines[lineNumber - 1].content
|
||||
|
||||
// Skip if no trailing whitespace
|
||||
guard let trailingWhitespaceInfo = line.trailingWhitespaceInfo() else {
|
||||
continue
|
||||
}
|
||||
|
||||
// Get the effective content (before trailing whitespace)
|
||||
let effectiveContent = getEffectiveContent(from: line, removing: trailingWhitespaceInfo)
|
||||
|
||||
// Check if the effective content ends with a comment
|
||||
if checkIfContentEndsWithComment(
|
||||
effectiveContent,
|
||||
lineNumber: lineNumber,
|
||||
lineCommentRanges: lineCommentRanges
|
||||
) {
|
||||
linesEndingWithComment.insert(lineNumber)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/// Gets the content of a line before its trailing whitespace
|
||||
private func getEffectiveContent(
|
||||
from line: String,
|
||||
removing trailingWhitespaceInfo: TrailingWhitespaceInfo
|
||||
) -> String {
|
||||
if trailingWhitespaceInfo.characterCount > 0 && line.count >= trailingWhitespaceInfo.characterCount {
|
||||
return String(line.prefix(line.count - trailingWhitespaceInfo.characterCount))
|
||||
}
|
||||
return ""
|
||||
}
|
||||
|
||||
/// Checks if the given content ends with a comment
|
||||
private func checkIfContentEndsWithComment(
|
||||
_ effectiveContent: String,
|
||||
lineNumber: Int,
|
||||
lineCommentRanges: [Int: [Range<AbsolutePosition>]]
|
||||
) -> Bool {
|
||||
guard !effectiveContent.isEmpty,
|
||||
let lastNonWhitespaceIdx = effectiveContent.lastIndex(where: { !$0.isWhitespace }) else {
|
||||
return false
|
||||
}
|
||||
|
||||
return !configuration.ignoresEmptyLines ||
|
||||
// If configured, ignore lines that contain nothing but whitespace (empty lines)
|
||||
$0.content.trimmingCharacters(in: .whitespaces).isNotEmpty
|
||||
// Calculate the byte position of the last non-whitespace character
|
||||
let contentUpToLastChar = effectiveContent.prefix(through: lastNonWhitespaceIdx)
|
||||
let byteOffsetToLastChar = contentUpToLastChar.utf8.count - 1 // -1 for position of char
|
||||
let lineStartPos = locationConverter.position(ofLine: lineNumber, column: 1)
|
||||
let lastNonWhitespacePos = lineStartPos.advanced(by: byteOffsetToLastChar)
|
||||
|
||||
// Check if this position falls within any comment range on this line
|
||||
if let ranges = lineCommentRanges[lineNumber] {
|
||||
for range in ranges {
|
||||
if range.lowerBound <= lastNonWhitespacePos && lastNonWhitespacePos < range.upperBound {
|
||||
return true
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return false
|
||||
}
|
||||
|
||||
return filteredLines.map {
|
||||
StyleViolation(ruleDescription: Self.description,
|
||||
severity: configuration.severityConfiguration.severity,
|
||||
location: Location(file: file.path, line: $0.index))
|
||||
/// Collects line numbers that are fully covered by block comments
|
||||
private func collectLinesFullyCoveredByBlockComments(_ sourceFile: SourceFileSyntax) {
|
||||
for token in sourceFile.tokens(viewMode: .sourceAccurate) {
|
||||
var currentPos = token.position
|
||||
|
||||
// Process leading trivia
|
||||
for piece in token.leadingTrivia {
|
||||
let pieceStartPos = currentPos
|
||||
currentPos += piece.sourceLength
|
||||
|
||||
if piece.isBlockComment {
|
||||
markLinesFullyCoveredByBlockComment(
|
||||
blockCommentStart: pieceStartPos,
|
||||
blockCommentEnd: currentPos
|
||||
)
|
||||
}
|
||||
}
|
||||
|
||||
// Advance past token content
|
||||
currentPos = token.endPositionBeforeTrailingTrivia
|
||||
|
||||
// Process trailing trivia
|
||||
for piece in token.trailingTrivia {
|
||||
let pieceStartPos = currentPos
|
||||
currentPos += piece.sourceLength
|
||||
|
||||
if piece.isBlockComment {
|
||||
markLinesFullyCoveredByBlockComment(
|
||||
blockCommentStart: pieceStartPos,
|
||||
blockCommentEnd: currentPos
|
||||
)
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func correct(file: SwiftLintFile) -> Int {
|
||||
let whitespaceCharacterSet = CharacterSet.whitespaces
|
||||
var correctedLines = [String]()
|
||||
var numberOfCorrections = 0
|
||||
for line in file.lines {
|
||||
guard line.content.hasTrailingWhitespace() else {
|
||||
correctedLines.append(line.content)
|
||||
continue
|
||||
/// Marks lines that are fully covered by a block comment
|
||||
private func markLinesFullyCoveredByBlockComment(
|
||||
blockCommentStart: AbsolutePosition,
|
||||
blockCommentEnd: AbsolutePosition
|
||||
) {
|
||||
let startLocation = locationConverter.location(for: blockCommentStart)
|
||||
let endLocation = locationConverter.location(for: blockCommentEnd)
|
||||
|
||||
let startLine = startLocation.line
|
||||
var endLine = endLocation.line
|
||||
|
||||
// If comment ends at column 1, it actually ended on the previous line
|
||||
if endLocation.column == 1 && endLine > startLine {
|
||||
endLine -= 1
|
||||
}
|
||||
|
||||
let commentKinds = SyntaxKind.commentKinds
|
||||
if configuration.ignoresComments,
|
||||
let lastSyntaxKind = file.syntaxKindsByLines[line.index].last,
|
||||
commentKinds.contains(lastSyntaxKind) {
|
||||
correctedLines.append(line.content)
|
||||
continue
|
||||
}
|
||||
for lineNum in startLine...endLine {
|
||||
if lineNum <= 0 || lineNum > file.lines.count { continue }
|
||||
|
||||
let correctedLine = line.content.bridge()
|
||||
.trimmingTrailingCharacters(in: whitespaceCharacterSet)
|
||||
let lineInfo = file.lines[lineNum - 1]
|
||||
let lineContent = lineInfo.content
|
||||
let lineStartPos = locationConverter.position(ofLine: lineNum, column: 1)
|
||||
|
||||
if configuration.ignoresEmptyLines && correctedLine.isEmpty {
|
||||
correctedLines.append(line.content)
|
||||
continue
|
||||
}
|
||||
// Check if the line's non-whitespace content is fully within the block comment
|
||||
if let firstNonWhitespaceIdx = lineContent.firstIndex(where: { !$0.isWhitespace }),
|
||||
let lastNonWhitespaceIdx = lineContent.lastIndex(where: { !$0.isWhitespace }) {
|
||||
// Line has non-whitespace content
|
||||
// Calculate byte offsets (not character offsets) for AbsolutePosition
|
||||
let contentBeforeFirstNonWS = lineContent.prefix(upTo: firstNonWhitespaceIdx)
|
||||
let byteOffsetToFirstNonWS = contentBeforeFirstNonWS.utf8.count
|
||||
let firstNonWhitespacePos = lineStartPos.advanced(by: byteOffsetToFirstNonWS)
|
||||
|
||||
if file.ruleEnabled(violatingRanges: [line.range], for: self).isEmpty {
|
||||
correctedLines.append(line.content)
|
||||
continue
|
||||
}
|
||||
let contentBeforeLastNonWS = lineContent.prefix(upTo: lastNonWhitespaceIdx)
|
||||
let byteOffsetToLastNonWS = contentBeforeLastNonWS.utf8.count
|
||||
let lastNonWhitespacePos = lineStartPos.advanced(by: byteOffsetToLastNonWS)
|
||||
|
||||
if line.content != correctedLine {
|
||||
numberOfCorrections += 1
|
||||
// Check if both first and last non-whitespace positions are within the comment
|
||||
if firstNonWhitespacePos >= blockCommentStart && lastNonWhitespacePos < blockCommentEnd {
|
||||
linesFullyCoveredByBlockComments.insert(lineNum)
|
||||
}
|
||||
} else {
|
||||
// Line is all whitespace - check if it's within the comment bounds
|
||||
let lineEndPos = lineStartPos.advanced(by: lineContent.utf8.count)
|
||||
if lineStartPos >= blockCommentStart && lineEndPos <= blockCommentEnd {
|
||||
linesFullyCoveredByBlockComments.insert(lineNum)
|
||||
}
|
||||
}
|
||||
}
|
||||
correctedLines.append(correctedLine)
|
||||
}
|
||||
if numberOfCorrections > 0 {
|
||||
// join and re-add trailing newline
|
||||
file.write(correctedLines.joined(separator: "\n") + "\n")
|
||||
}
|
||||
return numberOfCorrections
|
||||
}
|
||||
}
|
||||
|
||||
// Helper struct to return both character count and byte length for whitespace
|
||||
private struct TrailingWhitespaceInfo {
|
||||
let characterCount: Int
|
||||
let byteLength: Int
|
||||
}
|
||||
|
||||
private extension String {
|
||||
func hasTrailingWhitespace() -> Bool {
|
||||
if isEmpty { return false }
|
||||
guard let lastScalar = unicodeScalars.last else { return false }
|
||||
return CharacterSet.whitespaces.contains(lastScalar)
|
||||
}
|
||||
|
||||
/// Returns information about trailing whitespace (spaces and tabs only)
|
||||
func trailingWhitespaceInfo() -> TrailingWhitespaceInfo? {
|
||||
var charCount = 0
|
||||
var byteLen = 0
|
||||
for char in self.reversed() {
|
||||
if char.isWhitespace && (char == " " || char == "\t") { // Only count spaces and tabs
|
||||
charCount += 1
|
||||
byteLen += char.utf8.count
|
||||
} else {
|
||||
break
|
||||
}
|
||||
}
|
||||
return charCount > 0 ? TrailingWhitespaceInfo(characterCount: charCount, byteLength: byteLen) : nil
|
||||
}
|
||||
|
||||
func trimmingTrailingCharacters(in characterSet: CharacterSet) -> String {
|
||||
var end = endIndex
|
||||
while end > startIndex {
|
||||
let index = index(before: end)
|
||||
if !characterSet.contains(self[index].unicodeScalars.first!) {
|
||||
break
|
||||
}
|
||||
end = index
|
||||
}
|
||||
return String(self[..<end])
|
||||
}
|
||||
}
|
||||
|
||||
private extension TriviaPiece {
|
||||
var isBlockComment: Bool {
|
||||
switch self {
|
||||
case .blockComment, .docBlockComment:
|
||||
return true
|
||||
default:
|
||||
return false
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
Reference in New Issue
Block a user