Make SortedImportsRule auto-correctable

CHANGELOG.md

@@ -41,6 +41,17 @@
 * Add `catch` to the statements checked by the `control_statement` rule.  
   [JP Simard](https://github.com/jpsim)
 
+* Make `sorted_imports` correctable.  
+  [Samuel Susla](https://github.com/sammy-sc)
+  [JP Simard](https://github.com/jpsim)
+  [#1822](https://github.com/realm/SwiftLint/issues/1822)
+
+* Make `sorted_imports` only validate within import "groups" of imports on
+  directly adjacent lines.  
+  [Samuel Susla](https://github.com/sammy-sc)
+  [JP Simard](https://github.com/jpsim)
+  [#1822](https://github.com/realm/SwiftLint/issues/1822)
+
 ##### Bug Fixes
 
 * Correct equality tests for `Configuration` values. They previously didn't

Rules.md

@@ -10518,7 +10518,7 @@ class TotoTests {  }
 
 Identifier | Enabled by default | Supports autocorrection | Kind 
 --- | --- | --- | ---
-`sorted_imports` | Disabled | No | style
+`sorted_imports` | Disabled | Yes | style
 
 Imports should be sorted.
 
@@ -10544,6 +10544,37 @@ import labc
 import Ldef
 ```
 
+```swift
+import BBB
+// comment
+import AAA
+import CCC
+```
+
+```swift
+@testable import AAA
+import   CCC
+```
+
+```swift
+import AAA
+@testable import   CCC
+```
+
+```swift
+import EEE.A
+import FFF.B
+#if os(Linux)
+import DDD.A
+import EEE.B
+#else
+import CCC
+import DDD.B
+#endif
+import AAA
+import BBB
+```
+
 </details>
 <details>
 <summary>Triggering Examples</summary>
@@ -10555,6 +10586,37 @@ import ↓BBB
 import CCC
 ```
 
+```swift
+import DDD
+// comment
+import CCC
+import ↓AAA
+```
+
+```swift
+@testable import CCC
+import   ↓AAA
+```
+
+```swift
+import CCC
+@testable import   ↓AAA
+```
+
+```swift
+import FFF.B
+import ↓EEE.A
+#if os(Linux)
+import DDD.A
+import EEE.B
+#else
+import DDD.B
+import ↓CCC
+#endif
+import AAA
+import BBB
+```
+
 </details>
 
 

Source/SwiftLintFramework/Rules/SortedImportsRule.swift

@@ -9,7 +9,52 @@
 import Foundation
 import SourceKittenFramework
 
-public struct SortedImportsRule: ConfigurationProviderRule, OptInRule {
+extension Line {
+    fileprivate var contentRange: NSRange {
+        return NSRange(location: range.location, length: content.bridge().length)
+    }
+
+    // `Line` in this rule always contains word import
+    // This method returns contents of line that are after import
+    private func importModule() -> Substring {
+        return content[importModuleRange()]
+    }
+
+    fileprivate func importModuleRange() -> Range<String.Index> {
+        let rangeOfImport = content.range(of: "import")
+        precondition(rangeOfImport != nil)
+        let moduleStart = content.rangeOfCharacter(from: CharacterSet.whitespaces.inverted, options: [],
+                                                   range: rangeOfImport!.upperBound..<content.endIndex)
+        return moduleStart!.lowerBound..<content.endIndex
+    }
+
+    // Case insensitive comparison of contents of the line
+    // after the word `import`
+    fileprivate static func <= (lhs: Line, rhs: Line) -> Bool {
+        return lhs.importModule().lowercased() <= rhs.importModule().lowercased()
+    }
+}
+
+private extension Sequence where Element == Line {
+    // Groups lines, so that lines that are one after the other
+    // will end up in same group.
+    func grouped() -> [[Line]] {
+        return reduce([[]]) { result, line in
+            guard let last = result.last?.last else {
+                return [[line]]
+            }
+            var copy = result
+            if last.index == line.index - 1 {
+                copy[copy.count - 1].append(line)
+            } else {
+                copy.append([line])
+            }
+            return copy
+        }
+    }
+}
+
+public struct SortedImportsRule: CorrectableRule, ConfigurationProviderRule, OptInRule {
     public var configuration = SeverityConfiguration(.warning)
 
     public init() {}
@@ -22,36 +67,145 @@ public struct SortedImportsRule: ConfigurationProviderRule, OptInRule {
         nonTriggeringExamples: [
             "import AAA\nimport BBB\nimport CCC\nimport DDD",
             "import Alamofire\nimport API",
-            "import labc\nimport Ldef"
+            "import labc\nimport Ldef",
+            "import BBB\n// comment\nimport AAA\nimport CCC",
+            "@testable import AAA\nimport   CCC",
+            "import AAA\n@testable import   CCC",
+            """
+            import EEE.A
+            import FFF.B
+            #if os(Linux)
+            import DDD.A
+            import EEE.B
+            #else
+            import CCC
+            import DDD.B
+            #endif
+            import AAA
+            import BBB
+            """
         ],
         triggeringExamples: [
-            "import AAA\nimport ZZZ\nimport ↓BBB\nimport CCC"
+            "import AAA\nimport ZZZ\nimport ↓BBB\nimport CCC",
+            "import DDD\n// comment\nimport CCC\nimport ↓AAA",
+            "@testable import CCC\nimport   ↓AAA",
+            "import CCC\n@testable import   ↓AAA",
+            """
+            import FFF.B
+            import ↓EEE.A
+            #if os(Linux)
+            import DDD.A
+            import EEE.B
+            #else
+            import DDD.B
+            import ↓CCC
+            #endif
+            import AAA
+            import BBB
+            """
+        ],
+        corrections: [
+            "import AAA\nimport ZZZ\nimport ↓BBB\nimport CCC": "import AAA\nimport BBB\nimport CCC\nimport ZZZ",
+            "import BBB // comment\nimport ↓AAA": "import AAA\nimport BBB // comment",
+            "import BBB\n// comment\nimport CCC\nimport ↓AAA": "import BBB\n// comment\nimport AAA\nimport CCC",
+            "@testable import CCC\nimport  ↓AAA": "import  AAA\n@testable import CCC",
+            "import CCC\n@testable import  ↓AAA": "@testable import  AAA\nimport CCC",
+            """
+            import FFF.B
+            import ↓EEE.A
+            #if os(Linux)
+            import DDD.A
+            import EEE.B
+            #else
+            import DDD.B
+            import ↓CCC
+            #endif
+            import AAA
+            import BBB
+            """:
+            """
+            import EEE.A
+            import FFF.B
+            #if os(Linux)
+            import DDD.A
+            import EEE.B
+            #else
+            import CCC
+            import DDD.B
+            #endif
+            import AAA
+            import BBB
+            """
         ]
     )
 
     public func validate(file: File) -> [StyleViolation] {
-        let importRanges = file.match(pattern: "import\\s+\\w+", with: [.keyword, .identifier])
+        let groups = importGroups(in: file, filterEnabled: false)
+        return violatingOffsets(inGroups: groups).map { index -> StyleViolation in
+            let location = Location(file: file, characterOffset: index)
+            return StyleViolation(ruleDescription: type(of: self).description,
+                                  severity: configuration.severity,
+                                  location: location)
+        }
+    }
+
+    private func importGroups(in file: File, filterEnabled: Bool) -> [[Line]] {
+        var importRanges = file.match(pattern: "import\\s+\\w+", with: [.keyword, .identifier])
+        if filterEnabled {
+            importRanges = file.ruleEnabled(violatingRanges: importRanges, for: self)
+        }
+
         let contents = file.contents.bridge()
+        let lines = contents.lines()
+        let importLines: [Line] = importRanges.flatMap { range in
+            guard let line = contents.lineAndCharacter(forCharacterOffset: range.location)?.line
+                else { return nil }
+            return lines[line - 1]
+        }
 
-        let importLength = 6
-        let modulesAndOffsets: [(String, Int)] = importRanges.map { range in
-            let moduleRange = NSRange(location: range.location + importLength,
-                                      length: range.length - importLength)
-            let moduleName = contents.substring(with: moduleRange)
-                .trimmingCharacters(in: .whitespacesAndNewlines).lowercased()
-            let offset = NSMaxRange(range) - moduleName.bridge().length
-            return (moduleName, offset)
+        return importLines.grouped()
+    }
+
+    private func violatingOffsets(inGroups groups: [[Line]]) -> [Int] {
+        return groups.flatMap { group in
+            return zip(group, group.dropFirst()).reduce([]) { violatingOffsets, groupPair in
+                let (previous, current) = groupPair
+                let isOrderedCorrectly = previous <= current
+                if isOrderedCorrectly {
+                    return violatingOffsets
+                }
+                let distance = current.content.distance(from: current.content.startIndex,
+                                                        to: current.importModuleRange().lowerBound)
+                return violatingOffsets + [current.range.location + distance]
+            }
+        }
+    }
+
+    public func correct(file: File) -> [Correction] {
+        let groups = importGroups(in: file, filterEnabled: true)
+
+        let corrections = violatingOffsets(inGroups: groups).map { characterOffset -> Correction in
+            let location = Location(file: file, characterOffset: characterOffset)
+            return Correction(ruleDescription: type(of: self).description, location: location)
         }
 
-        let modulePairs = zip(modulesAndOffsets, modulesAndOffsets.dropFirst())
-        let violatingOffsets = modulePairs.flatMap { previous, current in
-            return current < previous ? current.1 : nil
+        guard !corrections.isEmpty else {
+            return []
         }
 
-        return violatingOffsets.map {
-            StyleViolation(ruleDescription: type(of: self).description,
-                           severity: configuration.severity,
-                           location: Location(file: file, characterOffset: $0))
+        let correctedContents = NSMutableString(string: file.contents)
+        for group in groups.map({ $0.sorted(by: <=) }) {
+            guard let first = group.first?.contentRange else {
+                continue
+            }
+            let result = group.map { $0.content }.joined(separator: "\n")
+            let union = group.dropFirst().reduce(first) { result, line in
+                return NSUnionRange(result, line.contentRange)
+            }
+            correctedContents.replaceCharacters(in: union, with: result)
         }
+        file.write(correctedContents.bridge())
+
+        return corrections
     }
 }

Source/swiftlint/Commands/RulesCommand.swift

@@ -6,7 +6,6 @@
 //  Copyright © 2015 Realm. All rights reserved.
 //
 
-// swiftlint:disable sorted_imports
 import Commandant
 #if os(Linux)
 import Glibc