Rewrite computed_accessors_order with SwiftSyntax (#4165)

2026-06-06 20:18:40 +00:00 · 2022-09-06 09:24:54 -07:00
parent 1e7e0d6301
commit dd94d4ec53
1 changed files with 56 additions and 102 deletions
@@ -1,7 +1,6 @@
-import Foundation
-import SourceKittenFramework
+import SwiftSyntax

-public struct ComputedAccessorsOrderRule: ConfigurationProviderRule {
+public struct ComputedAccessorsOrderRule: ConfigurationProviderRule, SourceKitFreeRule {
    public var configuration = ComputedAccessorsOrderRuleConfiguration()

    public init() {}
@@ -16,116 +15,71 @@ public struct ComputedAccessorsOrderRule: ConfigurationProviderRule {
    )

    public func validate(file: SwiftLintFile) -> [StyleViolation] {
-        let getTokens = findKeywordTokens(keyword: "get", file: file)
-
-        let violatingLocations = getTokens.compactMap { getToken -> (ByteCount, SwiftDeclarationKind?)? in
-            // the last element is the deepest structure
-            guard let dict = declarations(forByteOffset: getToken.offset,
-                                          structureDictionary: file.structureDictionary).last else {
-                return nil
+        ComputedAccessorsOrderRuleVisitor(expectedOrder: configuration.order)
+            .walk(file: file, handler: \.violationPositions)
+            .sorted { $0.position < $1.position }
+            .map { violation in
+                StyleViolation(
+                    ruleDescription: Self.description,
+                    severity: configuration.severityConfiguration.severity,
+                    location: Location(file: file, position: violation.position),
+                    reason: reason(for: violation.kind)
+                )
            }
-
-            guard let range = dict.byteRange.map(file.stringView.byteRangeToNSRange) else {
-                return nil
-            }
-
-            let setTokens = findKeywordTokens(keyword: "set", file: file, range: range)
-            let setToken = setTokens.first { token in
-                // the last element is the deepest structure
-                guard let setDict = declarations(forByteOffset: token.offset,
-                                                 structureDictionary: file.structureDictionary).last else {
-                    return false
-                }
-
-                return setDict.offset == dict.offset
-            }
-
-            let tokensInOrder = [getToken, setToken].compactMap { $0?.offset }.sorted()
-            let expectedOrder: [ByteCount]
-            switch configuration.order {
-            case .getSet:
-                expectedOrder = [getToken, setToken].compactMap { $0?.offset }
-            case .setGet:
-                expectedOrder = [setToken, getToken].compactMap { $0?.offset }
-            }
-
-            guard tokensInOrder != expectedOrder else {
-                return nil
-            }
-
-            let kind = dict.declarationKind
-            return (tokensInOrder[0], kind)
-        }
-
-        return violatingLocations.map { offset, kind in
-            let reason = kind.map { kind -> String in
-                let kindString = kind == .functionSubscript ? "subscripts" : "properties"
-                let orderString: String
-                switch configuration.order {
-                case .getSet:
-                    orderString = "getter and then the setter"
-                case .setGet:
-                    orderString = "setter and then the getter"
-                }
-                return "Computed \(kindString) should declare first the \(orderString)."
-            }
-
-            return StyleViolation(ruleDescription: Self.description,
-                                  severity: configuration.severityConfiguration.severity,
-                                  location: Location(file: file, byteOffset: offset),
-                                  reason: reason)
-        }
    }

-    private func findKeywordTokens(keyword: String,
-                                   file: SwiftLintFile,
-                                   range: NSRange? = nil) -> [SwiftLintSyntaxToken] {
-        let pattern = "\\b\(keyword)\\b"
-        return file.rangesAndTokens(matching: pattern, range: range).compactMap { _, tokens in
-            guard tokens.count == 1,
-                let token = tokens.last,
-                token.kind == .keyword else {
-                    return nil
-            }
-
-            return token
+    private func reason(for kind: ComputedAccessorsOrderRuleVisitor.ViolationKind) -> String {
+        let kindString = kind == .subscript ? "subscripts" : "properties"
+        let orderString: String
+        switch configuration.order {
+        case .getSet:
+            orderString = "getter and then the setter"
+        case .setGet:
+            orderString = "setter and then the getter"
        }
+        return "Computed \(kindString) should declare first the \(orderString)."
    }
 }

-private extension ComputedAccessorsOrderRule {
-    func declarations(forByteOffset byteOffset: ByteCount,
-                      structureDictionary: SourceKittenDictionary) -> [SourceKittenDictionary] {
-        var results = [SourceKittenDictionary]()
-        let allowedKinds = SwiftDeclarationKind.variableKinds.subtracting([.varParameter])
-            .union([.functionSubscript])
+private final class ComputedAccessorsOrderRuleVisitor: SyntaxVisitor {
+    enum ViolationKind {
+        case `subscript`, property
+    }

-        func parse(dictionary: SourceKittenDictionary,
-                   parentKind: SwiftDeclarationKind?,
-                   into results: inout [SourceKittenDictionary]) {
-            // Only accepts declarations which contains a body and contains the
-            // searched byteOffset
-            guard let kind = dictionary.declarationKind,
-                let byteRange = dictionary.byteRange,
-                byteRange.contains(byteOffset)
-            else {
-                return
-            }
+    private(set) var violationPositions: [(position: AbsolutePosition, kind: ViolationKind)] = []
+    private let expectedOrder: ComputedAccessorsOrderRuleConfiguration.Order

-            if parentKind != .protocol && allowedKinds.contains(kind) {
-                results.append(dictionary)
-            }
+    init(expectedOrder: ComputedAccessorsOrderRuleConfiguration.Order) {
+        self.expectedOrder = expectedOrder
+    }

-            for dictionary in dictionary.substructure {
-                parse(dictionary: dictionary, parentKind: kind, into: &results)
-            }
+    override func visitPost(_ node: AccessorBlockSyntax) {
+        guard let firstAccessor = node.accessors.first,
+              let order = node.order,
+              order != expectedOrder else {
+            return
        }

-        let dict = structureDictionary
-        for dictionary in dict.substructure {
-            parse(dictionary: dictionary, parentKind: nil, into: &results)
-        }
-
-        return results
+        let kind: ViolationKind = node.parent?.as(SubscriptDeclSyntax.self) == nil ? .property : .subscript
+        violationPositions.append((firstAccessor.positionAfterSkippingLeadingTrivia, kind))
+    }
+}
+
+private extension AccessorBlockSyntax {
+    var order: ComputedAccessorsOrderRuleConfiguration.Order? {
+        guard accessors.count == 2, accessors.map(\.body).allSatisfy({ $0 != nil }) else {
+            return nil
+        }
+
+        let tokens = accessors.map(\.accessorKind.tokenKind)
+        if tokens == [.contextualKeyword("get"), .contextualKeyword("set")] {
+            return .getSet
+        }
+
+        if tokens == [.contextualKeyword("set"), .contextualKeyword("get")] {
+            return .setGet
+        }
+
+        return nil
    }
 }