Add headerFileName rule

Rules.md

@@ -18,6 +18,7 @@
 * [extensionAccessControl](#extensionAccessControl)
 * [fileHeader](#fileHeader)
 * [genericExtensions](#genericExtensions)
+* [headerFileName](#headerFileName)
 * [hoistAwait](#hoistAwait)
 * [hoistPatternLet](#hoistPatternLet)
 * [hoistTry](#hoistTry)
@@ -785,6 +786,10 @@ Option | Description
 </details>
 <br/>
 
+## headerFileName
+
+Ensure file name reference in header matches actual file name.
+
 ## hoistAwait
 
 Move inline `await` keyword(s) to start of expression.

Snapshots/Consumer/Sources/ConsumerCompiler.swift

@@ -1,5 +1,5 @@
 //
-//  Consumer.swift
+//  ConsumerCompiler.swift
 //  Consumer
 //
 //  Created by Nick Lockwood on 03/03/2018.

Snapshots/Expression/Tests/AnyExpressionTests.swift

@@ -1,5 +1,5 @@
 //
-//  ExpressionTests.swift
+//  AnyExpressionTests.swift
 //  ExpressionTests
 //
 //  Created by Nick Lockwood on 18/04/2017.

Sources/JSONReporter.swift

@@ -1,5 +1,5 @@
 //
-//  CommandLine.swift
+//  JSONReporter.swift
 //  SwiftFormat
 //
 //  Created by Daniele Formichelli on 09/04/2021.

Sources/ParsingHelpers.swift

@@ -1944,6 +1944,94 @@ extension Formatter {
         }
     }
 
+    // Range of tokens forming file header comment
+    var headerCommentTokenRange: Range<Int>? {
+        guard !options.fragment else {
+            return nil
+        }
+        var start = 0
+        var lastHeaderTokenIndex = -1
+        if var startIndex = index(of: .nonSpaceOrLinebreak, after: -1) {
+            if tokens[startIndex] == .startOfScope("#!") {
+                guard let endIndex = index(of: .linebreak, after: startIndex) else {
+                    return nil
+                }
+                startIndex = index(of: .nonSpaceOrLinebreak, after: endIndex) ?? endIndex
+                start = startIndex
+                lastHeaderTokenIndex = startIndex - 1
+            }
+            switch tokens[startIndex] {
+            case .startOfScope("//"):
+                if case let .commentBody(body)? = next(.nonSpace, after: startIndex) {
+                    processCommentBody(body, at: startIndex)
+                    defer {
+                        processLinebreak()
+                        processLinebreak()
+                    }
+                    if !isEnabled || (body.hasPrefix("/") && !body.hasPrefix("//")) ||
+                        body.hasPrefix("swift-tools-version")
+                    {
+                        return nil
+                    } else if body.isCommentDirective {
+                        break
+                    }
+                }
+                var lastIndex = startIndex
+                while let index = index(of: .linebreak, after: lastIndex) {
+                    switch token(at: index + 1) ?? .space("") {
+                    case .startOfScope("//"):
+                        if case let .commentBody(body)? = next(.nonSpace, after: index + 1),
+                           body.isCommentDirective
+                        {
+                            break
+                        }
+                        lastIndex = index
+                        continue
+                    case .linebreak:
+                        lastHeaderTokenIndex = index + 1
+                    case .space where token(at: index + 2)?.isLinebreak == true:
+                        lastHeaderTokenIndex = index + 2
+                    default:
+                        break
+                    }
+                    break
+                }
+            case .startOfScope("/*"):
+                if case let .commentBody(body)? = next(.nonSpace, after: startIndex) {
+                    processCommentBody(body, at: startIndex)
+                    defer {
+                        processLinebreak()
+                        processLinebreak()
+                    }
+                    if !isEnabled || (body.hasPrefix("*") && !body.hasPrefix("**")) {
+                        return nil
+                    } else if body.isCommentDirective {
+                        break
+                    }
+                }
+                while let endIndex = index(of: .endOfScope("*/"), after: startIndex) {
+                    lastHeaderTokenIndex = endIndex
+                    if let linebreakIndex = index(of: .linebreak, after: endIndex) {
+                        lastHeaderTokenIndex = linebreakIndex
+                    }
+                    guard let nextIndex = index(of: .nonSpace, after: lastHeaderTokenIndex) else {
+                        break
+                    }
+                    guard tokens[nextIndex] == .startOfScope("/*") else {
+                        if let endIndex = index(of: .nonSpaceOrLinebreak, after: lastHeaderTokenIndex) {
+                            lastHeaderTokenIndex = endIndex - 1
+                        }
+                        break
+                    }
+                    startIndex = nextIndex
+                }
+            default:
+                break
+            }
+        }
+        return start ..< lastHeaderTokenIndex + 1
+    }
+
     struct SwitchCaseRange {
         let beforeDelimiterRange: Range<Int>
         let delimiterToken: Token

Sources/Reporter.swift

@@ -1,5 +1,5 @@
 //
-//  Report.swift
+//  Reporter.swift
 //  SwiftFormat
 //
 //  Created by Jonas Boberg on 2023/02/13.

Sources/Rules.swift

@@ -4994,7 +4994,9 @@ public struct _FormatRules {
         options: ["header"],
         sharedOptions: ["linebreaks"]
     ) { formatter in
-        guard !formatter.options.fragment else { return }
+        guard let headerRange = formatter.headerCommentTokenRange else {
+            return
+        }
 
         let header: String
         switch formatter.options.fileHeader {
@@ -5021,83 +5023,14 @@ public struct _FormatRules {
             }
             header = string
         }
-        var start = 0
-        var lastHeaderTokenIndex = -1
-        if var startIndex = formatter.index(of: .nonSpaceOrLinebreak, after: -1) {
-            if formatter.tokens[startIndex] == .startOfScope("#!") {
-                guard let endIndex = formatter.index(of: .linebreak, after: startIndex) else {
-                    return
-                }
-                startIndex = formatter.index(of: .nonSpaceOrLinebreak, after: endIndex) ?? endIndex
-                start = startIndex
-                lastHeaderTokenIndex = startIndex - 1
-            }
-            switch formatter.tokens[startIndex] {
-            case .startOfScope("//"):
-                if case let .commentBody(body)? = formatter.next(.nonSpace, after: startIndex) {
-                    formatter.processCommentBody(body, at: startIndex)
-                    if !formatter.isEnabled || (body.hasPrefix("/") && !body.hasPrefix("//")) ||
-                        body.hasPrefix("swift-tools-version")
-                    {
-                        return
-                    } else if body.isCommentDirective {
-                        break
-                    }
-                }
-                var lastIndex = startIndex
-                while let index = formatter.index(of: .linebreak, after: lastIndex) {
-                    switch formatter.token(at: index + 1) ?? .space("") {
-                    case .startOfScope("//"):
-                        if case let .commentBody(body)? = formatter.next(.nonSpace, after: index + 1),
-                           body.isCommentDirective
-                        {
-                            break
-                        }
-                        lastIndex = index
-                        continue
-                    case .linebreak:
-                        lastHeaderTokenIndex = index + 1
-                    case .space where formatter.token(at: index + 2)?.isLinebreak == true:
-                        lastHeaderTokenIndex = index + 2
-                    default:
-                        break
-                    }
-                    break
-                }
-            case .startOfScope("/*"):
-                if case let .commentBody(body)? = formatter.next(.nonSpace, after: startIndex) {
-                    formatter.processCommentBody(body, at: startIndex)
-                    if !formatter.isEnabled || (body.hasPrefix("*") && !body.hasPrefix("**")) {
-                        return
-                    } else if body.isCommentDirective {
-                        break
-                    }
-                }
-                while let endIndex = formatter.index(of: .endOfScope("*/"), after: startIndex) {
-                    lastHeaderTokenIndex = endIndex
-                    if let linebreakIndex = formatter.index(of: .linebreak, after: endIndex) {
-                        lastHeaderTokenIndex = linebreakIndex
-                    }
-                    guard let nextIndex = formatter.index(of: .nonSpace, after: lastHeaderTokenIndex) else {
-                        break
-                    }
-                    guard formatter.tokens[nextIndex] == .startOfScope("/*") else {
-                        if let endIndex = formatter.index(of: .nonSpaceOrLinebreak, after: lastHeaderTokenIndex) {
-                            lastHeaderTokenIndex = endIndex - 1
-                        }
-                        break
-                    }
-                    startIndex = nextIndex
-                }
-            default:
-                break
-            }
-        }
+
         if header.isEmpty {
-            formatter.removeTokens(in: start ..< lastHeaderTokenIndex + 1)
+            formatter.removeTokens(in: headerRange)
             return
         }
+
         var headerTokens = tokenize(header)
+        var lastHeaderTokenIndex = headerRange.endIndex - 1
         let endIndex = lastHeaderTokenIndex + headerTokens.count
         if formatter.tokens.endIndex > endIndex, headerTokens == Array(formatter.tokens[
             lastHeaderTokenIndex + 1 ... endIndex
@@ -5122,7 +5055,30 @@ public struct _FormatRules {
         }) {
             lastHeaderTokenIndex = index
         }
-        formatter.replaceTokens(in: start ..< lastHeaderTokenIndex + 1, with: headerTokens)
+        formatter.replaceTokens(in: headerRange.startIndex ..< lastHeaderTokenIndex + 1, with: headerTokens)
+    }
+
+    /// Ensure file name reference in header matches actual file name
+    public let headerFileName = FormatRule(
+        help: "Ensure file name reference in header matches actual file name.",
+        runOnceOnly: true,
+        orderAfter: ["fileHeader"]
+    ) { formatter in
+        guard let fileName = formatter.options.fileInfo.fileName,
+              let headerRange = formatter.headerCommentTokenRange,
+              fileName.hasSuffix(".swift")
+        else {
+            return
+        }
+
+        for i in headerRange {
+            guard case let .commentBody(body) = formatter.tokens[i] else {
+                continue
+            }
+            if body.hasSuffix(".swift"), body != fileName, !body.contains(where: { " /".contains($0) }) {
+                formatter.replaceToken(at: i, with: .commentBody(fileName))
+            }
+        }
     }
 
     /// Strip redundant `.init` from type instantiations

Tests/EnumAssociableTests.swift

@@ -1,5 +1,5 @@
 //
-//  EnumAssociableTest.swift
+//  EnumAssociableTests.swift
 //  SwiftFormat
 //
 //  Created by Vincent Bernier on 13-02-18.

Tests/OptionDescriptorTests.swift

@@ -1,5 +1,5 @@
 //
-//  OptionDescriptorTest.swift
+//  OptionDescriptorTests.swift
 //  SwiftFormatTests
 //
 //  Created by Vincent Bernier on 10-02-18.

Tests/RulesTests+General.swift

@@ -666,6 +666,23 @@ class GeneralTests: RulesTests {
         testFormatting(for: input, rule: FormatRules.fileHeader, options: options)
     }
 
+    // MARK: - headerFileName
+
+    func testHeaderFileNameReplaced() {
+        let input = """
+        // MyFile.swift
+
+        let foo = bar
+        """
+        let output = """
+        // YourFile.swift
+
+        let foo = bar
+        """
+        let options = FormatOptions(fileInfo: FileInfo(filePath: "~/YourFile.swift"))
+        testFormatting(for: input, output, rule: FormatRules.headerFileName, options: options)
+    }
+
     // MARK: - strongOutlets
 
     func testRemoveWeakFromOutlet() {

Tests/RulesTests+Organization.swift

@@ -1,5 +1,5 @@
 //
-//  RulesTests+Organize.swift
+//  RulesTests+Organization.swift
 //  SwiftFormatTests
 //
 //  Created by Nick Lockwood on 04/09/2020.

Tests/RulesTests+Spacing.swift

@@ -1,5 +1,5 @@
 //
-//  SpacingRulesTests.swift
+//  RulesTests+Spacing.swift
 //  SwiftFormatTests
 //
 //  Created by Nick Lockwood on 04/09/2020.