Cache Structure Dictionaries

CHANGELOG.md

@@ -2,7 +2,10 @@
 
 #### Breaking
 
-* None.
+* Use SourceKittenDictionary wrapper over dictionaries  
+  returned from SourceKitten  
+  [PaulTaykalo](https://github.com/PaulTaykalo)
+  [#2922](https://github.com/realm/SwiftLint/issues/2922)
 
 #### Experimental
 

Rules.md

@@ -24981,13 +24981,13 @@ Function parameters should be aligned vertically if they're in multiple lines in
 
 ```swift
 func validateFunction(_ file: File, kind: SwiftDeclarationKind,
-                      dictionary: [String: SourceKitRepresentable]) { }
+                      dictionary: SourceKittenDictionary) { }
 
 ```
 
 ```swift
 func validateFunction(_ file: File, kind: SwiftDeclarationKind,
-                      dictionary: [String: SourceKitRepresentable]) -> [StyleViolation]
+                      dictionary: SourceKittenDictionary) -> [StyleViolation]
 
 ```
 
@@ -25003,22 +25003,22 @@ func foo(bar: Int) -> String
 
 ```swift
 func validateFunction(_ file: File, kind: SwiftDeclarationKind,
-                      dictionary: [String: SourceKitRepresentable])
+                      dictionary: SourceKittenDictionary)
                       -> [StyleViolation]
 
 ```
 
 ```swift
 func validateFunction(
    _ file: File, kind: SwiftDeclarationKind,
-   dictionary: [String: SourceKitRepresentable]) -> [StyleViolation]
+   dictionary: SourceKittenDictionary) -> [StyleViolation]
 
 ```
 
 ```swift
 func validateFunction(
    _ file: File, kind: SwiftDeclarationKind,
-   dictionary: [String: SourceKitRepresentable]
+   dictionary: SourceKittenDictionary
 ) -> [StyleViolation]
 
 ```
@@ -25054,20 +25054,20 @@ func foo(data: Data,
 
 ```swift
 func validateFunction(_ file: File, kind: SwiftDeclarationKind,
-                  ↓dictionary: [String: SourceKitRepresentable]) { }
+                  ↓dictionary: SourceKittenDictionary) { }
 
 ```
 
 ```swift
 func validateFunction(_ file: File, kind: SwiftDeclarationKind,
-                       ↓dictionary: [String: SourceKitRepresentable]) { }
+                       ↓dictionary: SourceKittenDictionary) { }
 
 ```
 
 ```swift
 func validateFunction(_ file: File,
                   ↓kind: SwiftDeclarationKind,
-                  ↓dictionary: [String: SourceKitRepresentable]) { }
+                  ↓dictionary: SourceKittenDictionary) { }
 
 ```
 

Source/SwiftLintFramework/Extensions/Dictionary+SwiftLint.swift

@@ -1,87 +1,106 @@
 import SourceKittenFramework
 
-extension Dictionary where Key: ExpressibleByStringLiteral {
+public struct SourceKittenDictionary {
+    public let value: [String: SourceKitRepresentable]
+    public let substructure: [SourceKittenDictionary]
+
+    init(_ value: [String: SourceKitRepresentable]) {
+        self.value = value
+
+        let substructure = value["key.substructure"] as? [SourceKitRepresentable] ?? []
+        self.substructure = substructure.compactMap { $0 as? [String: SourceKitRepresentable] }
+            .map(SourceKittenDictionary.init)
+    }
+
     /// Accessibility.
     var accessibility: String? {
-        return self["key.accessibility"] as? String
+        return value["key.accessibility"] as? String
     }
-    /// Body length.
+
+    /// Body length
     var bodyLength: Int? {
-        return (self["key.bodylength"] as? Int64).flatMap({ Int($0) })
+        return (value["key.bodylength"] as? Int64).flatMap({ Int($0) })
     }
+
     /// Body offset.
     var bodyOffset: Int? {
-        return (self["key.bodyoffset"] as? Int64).flatMap({ Int($0) })
+        return (value["key.bodyoffset"] as? Int64).flatMap({ Int($0) })
     }
+
     /// Kind.
     var kind: String? {
-        return self["key.kind"] as? String
+        return value["key.kind"] as? String
     }
+
     /// Length.
     var length: Int? {
-        return (self["key.length"] as? Int64).flatMap({ Int($0) })
+        return (value["key.length"] as? Int64).flatMap({ Int($0) })
     }
     /// Name.
     var name: String? {
-        return self["key.name"] as? String
+        return value["key.name"] as? String
     }
+
     /// Name length.
     var nameLength: Int? {
-        return (self["key.namelength"] as? Int64).flatMap({ Int($0) })
+        return (value["key.namelength"] as? Int64).flatMap({ Int($0) })
     }
+
     /// Name offset.
     var nameOffset: Int? {
-        return (self["key.nameoffset"] as? Int64).flatMap({ Int($0) })
+        return (value["key.nameoffset"] as? Int64).flatMap({ Int($0) })
     }
+
     /// Offset.
     var offset: Int? {
-        return (self["key.offset"] as? Int64).flatMap({ Int($0) })
+        return (value["key.offset"] as? Int64).flatMap({ Int($0) })
     }
+
     /// Setter accessibility.
     var setterAccessibility: String? {
-        return self["key.setter_accessibility"] as? String
+        return value["key.setter_accessibility"] as? String
     }
+
     /// Type name.
     var typeName: String? {
-        return self["key.typename"] as? String
+        return value["key.typename"] as? String
     }
+
     /// Documentation length.
     var docLength: Int? {
-        return (self["key.doclength"] as? Int64).flatMap({ Int($0) })
+        return (value["key.doclength"] as? Int64).flatMap({ Int($0) })
     }
 
     var attribute: String? {
-        return self["key.attribute"] as? String
+        return value["key.attribute"] as? String
     }
 
     var enclosedSwiftAttributes: [SwiftDeclarationAttributeKind] {
         return swiftAttributes.compactMap { $0.attribute }
-                              .compactMap(SwiftDeclarationAttributeKind.init(rawValue:))
+            .compactMap(SwiftDeclarationAttributeKind.init(rawValue:))
     }
 
-    var swiftAttributes: [[String: SourceKitRepresentable]] {
-        let array = self["key.attributes"] as? [SourceKitRepresentable] ?? []
-        let dictionaries = array.compactMap { ($0 as? [String: SourceKitRepresentable]) }
+    var swiftAttributes: [SourceKittenDictionary] {
+        let array = value["key.attributes"] as? [SourceKitRepresentable] ?? []
+        let dictionaries = array.compactMap { $0 as? [String: SourceKitRepresentable] }
+            .map(SourceKittenDictionary.init)
         return dictionaries
     }
 
-    var substructure: [[String: SourceKitRepresentable]] {
-        let substructure = self["key.substructure"] as? [SourceKitRepresentable] ?? []
-        return substructure.compactMap { $0 as? [String: SourceKitRepresentable] }
-    }
-
-    var elements: [[String: SourceKitRepresentable]] {
-        let elements = self["key.elements"] as? [SourceKitRepresentable] ?? []
+    var elements: [SourceKittenDictionary] {
+        let elements = value["key.elements"] as? [SourceKitRepresentable] ?? []
         return elements.compactMap { $0 as? [String: SourceKitRepresentable] }
+        .map(SourceKittenDictionary.init)
     }
 
-    var entities: [[String: SourceKitRepresentable]] {
-        let entities = self["key.entities"] as? [SourceKitRepresentable] ?? []
+    var entities: [SourceKittenDictionary] {
+        let entities = value["key.entities"] as? [SourceKitRepresentable] ?? []
         return entities.compactMap { $0 as? [String: SourceKitRepresentable] }
+            .map(SourceKittenDictionary.init)
     }
 
-    var enclosedVarParameters: [[String: SourceKitRepresentable]] {
-        return substructure.flatMap { subDict -> [[String: SourceKitRepresentable]] in
+    var enclosedVarParameters: [SourceKittenDictionary] {
+        return substructure.flatMap { subDict -> [SourceKittenDictionary] in
             guard let kindString = subDict.kind else {
                 return []
             }
@@ -97,8 +116,8 @@ extension Dictionary where Key: ExpressibleByStringLiteral {
         }
     }
 
-    var enclosedArguments: [[String: SourceKitRepresentable]] {
-        return substructure.flatMap { subDict -> [[String: SourceKitRepresentable]] in
+    var enclosedArguments: [SourceKittenDictionary] {
+        return substructure.flatMap { subDict -> [SourceKittenDictionary] in
             guard let kindString = subDict.kind,
                 SwiftExpressionKind(rawValue: kindString) == .argument else {
                     return []
@@ -109,8 +128,8 @@ extension Dictionary where Key: ExpressibleByStringLiteral {
     }
 
     var inheritedTypes: [String] {
-        let array = self["key.inheritedtypes"] as? [SourceKitRepresentable] ?? []
-        return array.compactMap { ($0 as? [String: String])?.name }
+        let array = value["key.inheritedtypes"] as? [SourceKitRepresentable] ?? []
+        return array.compactMap { ($0 as? [String: String]).flatMap { $0["key.name"] } }
     }
 
     internal func extractCallsToSuper(methodName: String) -> [String] {

Source/SwiftLintFramework/Extensions/File+Cache.swift

@@ -18,6 +18,11 @@ private var structureCache = Cache({ file -> Structure? in
     }
     return nil
 })
+
+private var structureDictionaryCache = Cache({ file in
+    return structureCache.get(file).map { SourceKittenDictionary($0.dictionary) }
+})
+
 private var syntaxMapCache = Cache({ file in responseCache.get(file).map(SyntaxMap.init) })
 private var syntaxKindsByLinesCache = Cache({ file in file.syntaxKindsByLine() })
 private var syntaxTokensByLinesCache = Cache({ file in file.syntaxTokensByLine() })
@@ -128,6 +133,17 @@ extension File {
         return structure
     }
 
+    internal var structureDictionary: SourceKittenDictionary {
+        guard let structureDictionary = structureDictionaryCache.get(self) else {
+            if let handler = assertHandler {
+                handler()
+                return SourceKittenDictionary([:])
+            }
+            queuedFatalError("Never call this for file that sourcekitd fails.")
+        }
+        return structureDictionary
+    }
+
     internal var syntaxMap: SyntaxMap {
         guard let syntaxMap = syntaxMapCache.get(self) else {
             if let handler = assertHandler {
@@ -165,6 +181,7 @@ extension File {
         responseCache.invalidate(self)
         assertHandlerCache.invalidate(self)
         structureCache.invalidate(self)
+        structureDictionaryCache.invalidate(self)
         syntaxMapCache.invalidate(self)
         syntaxTokensByLinesCache.invalidate(self)
         syntaxKindsByLinesCache.invalidate(self)
@@ -175,6 +192,7 @@ extension File {
         responseCache.clear()
         assertHandlerCache.clear()
         structureCache.clear()
+        structureDictionaryCache.clear()
         syntaxMapCache.clear()
         syntaxTokensByLinesCache.clear()
         syntaxKindsByLinesCache.clear()

Source/SwiftLintFramework/Extensions/File+SwiftLint.swift

@@ -131,7 +131,7 @@ extension File {
         }
         var results = [[SwiftDeclarationKind]](repeating: [], count: lines.count + 1)
         var lineIterator = lines.makeIterator()
-        var structureIterator = structure.kinds().makeIterator()
+        var structureIterator = structureDictionary.kinds().makeIterator()
         var maybeLine = lineIterator.next()
         var maybeStructure = structureIterator.next()
         while let line = maybeLine, let structure = maybeStructure {

Source/SwiftLintFramework/Extensions/Structure+SwiftLint.swift → Source/SwiftLintFramework/Extensions/SourceKittenDictionary+Swiftlint.swift

@@ -1,15 +1,15 @@
 import Foundation
-import SourceKittenFramework
 
-extension Structure {
+extension SourceKittenDictionary {
     /// Returns array of tuples containing "key.kind" and "byteRange" from Structure
     /// that contains the byte offset. Returns all kinds if no parameter specified.
     ///
     /// - Parameter byteOffset: Int?
-    internal func kinds(forByteOffset byteOffset: Int? = nil) -> [(kind: String, byteRange: NSRange)] {
+    internal func kinds(forByteOffset byteOffset: Int? = nil)
+        -> [(kind: String, byteRange: NSRange)] {
         var results = [(kind: String, byteRange: NSRange)]()
 
-        func parse(_ dictionary: [String: SourceKitRepresentable]) {
+        func parse(_ dictionary: SourceKittenDictionary) {
             guard let offset = dictionary.offset,
                 let byteRange = dictionary.length.map({ NSRange(location: offset, length: $0) }) else {
                     return
@@ -22,14 +22,14 @@ extension Structure {
             }
             dictionary.substructure.forEach(parse)
         }
-        parse(dictionary)
+        parse(self)
         return results
     }
 
-    internal func structures(forByteOffset byteOffset: Int) -> [[String: SourceKitRepresentable]] {
-        var results = [[String: SourceKitRepresentable]]()
+    internal func structures(forByteOffset byteOffset: Int) -> [SourceKittenDictionary] {
+        var results = [SourceKittenDictionary]()
 
-        func parse(_ dictionary: [String: SourceKitRepresentable]) {
+        func parse(_ dictionary: SourceKittenDictionary) {
             guard let offset = dictionary.offset,
                 let byteRange = dictionary.length.map({ NSRange(location: offset, length: $0) }),
                 NSLocationInRange(byteOffset, byteRange) else {
@@ -39,7 +39,7 @@ extension Structure {
             results.append(dictionary)
             dictionary.substructure.forEach(parse)
         }
-        parse(dictionary)
+        parse(self)
         return results
     }
 }

Source/SwiftLintFramework/Extensions/String+SwiftLint.swift

@@ -22,7 +22,7 @@ extension String {
         return self == lowercased()
     }
 
-    internal func nameStrippingLeadingUnderscoreIfPrivate(_ dict: [String: SourceKitRepresentable]) -> String {
+    internal func nameStrippingLeadingUnderscoreIfPrivate(_ dict: SourceKittenDictionary) -> String {
         if let aclString = dict.accessibility,
            let acl = AccessControlLevel(identifier: aclString),
             acl.isPrivate && first == "_" {

Source/SwiftLintFramework/Helpers/NamespaceCollector.swift

@@ -5,9 +5,9 @@ struct NamespaceCollector {
         let name: String
         let kind: SwiftDeclarationKind
         let offset: Int
-        let dictionary: [String: SourceKitRepresentable]
+        let dictionary: SourceKittenDictionary
 
-        init?(dictionary: [String: SourceKitRepresentable], namespace: [String]) {
+        init?(dictionary: SourceKittenDictionary, namespace: [String]) {
             guard let name = dictionary.name,
                 let kind = dictionary.kind.flatMap(SwiftDeclarationKind.init),
                 let offset = dictionary.offset else {
@@ -21,9 +21,9 @@ struct NamespaceCollector {
         }
     }
 
-    private let dictionary: [String: SourceKitRepresentable]
+    private let dictionary: SourceKittenDictionary
 
-    init(dictionary: [String: SourceKitRepresentable]) {
+    init(dictionary: SourceKittenDictionary) {
         self.dictionary = dictionary
     }
 
@@ -32,7 +32,7 @@ struct NamespaceCollector {
         return findAllElements(in: dictionary, of: types, namespace: namespace)
     }
 
-    private func findAllElements(in dictionary: [String: SourceKitRepresentable],
+    private func findAllElements(in dictionary: SourceKittenDictionary,
                                  of types: Set<SwiftDeclarationKind>,
                                  namespace: [String] = []) -> [Element] {
         return dictionary.substructure.flatMap { subDict -> [Element] in

Source/SwiftLintFramework/Models/SwiftVersion.swift

@@ -104,7 +104,8 @@ public extension SwiftVersion {
             return token.type == SyntaxKind.string.rawValue
         }
         if !Request.disableSourceKit,
-            let decl = file.structure.kinds().first(where: { $0.kind == SwiftDeclarationKind.varGlobal.rawValue }),
+            let decl = file.structureDictionary.kinds()
+                .first(where: { $0.kind == SwiftDeclarationKind.varGlobal.rawValue }),
             let token = file.syntaxMap.tokens(inByteRange: decl.byteRange).first(where: isString ) {
             return .init(rawValue: file.contents.substring(from: token.offset + 1, length: token.length - 2))
         }