Parallelize iterating over subpaths (realm#2475)

This has a very small performance improvement on multi-core machines
l-lemesev · Nov 22, 2018 · d1109da · d1109da
1 parent ea171fb
commit d1109da
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Showing 3 changed files with 6 additions and 8 deletions.
diff --git a/Source/SwiftLintFramework/Extensions/Array+SwiftLint.swift b/Source/SwiftLintFramework/Extensions/Array+SwiftLint.swift
@@ -47,7 +47,7 @@ extension Array {
         return parallelMap(transform: transform).flatMap { $0 }
     }
 
-    func parallelFlatMap<T>(transform: @escaping ((Element) -> T?)) -> [T] {
+    func parallelCompactMap<T>(transform: @escaping ((Element) -> T?)) -> [T] {
         return parallelMap(transform: transform).compactMap { $0 }
     }
 

diff --git a/Source/SwiftLintFramework/Extensions/FileManager+SwiftLint.swift b/Source/SwiftLintFramework/Extensions/FileManager+SwiftLint.swift
@@ -19,14 +19,12 @@ extension FileManager: LintableFileManager {
 
 #if os(Linux)
         return enumerator(atPath: absolutePath)?.compactMap { element -> String? in
-            if let element = element as? String,
-                element.bridge().isSwiftFile() && (absolutePath + "/" + element).isFile {
-                return absolutePath.bridge().appendingPathComponent(element)
-            }
-            return nil
+            guard let element = element as? String, element.bridge().isSwiftFile() else { return nil }
+            let absoluteElementPath = absolutePath.bridge().appendingPathComponent(element)
+            return absoluteElementPath.isFile ? absoluteElementPath : nil
         } ?? []
 #else
-        return subpaths(atPath: absolutePath)?.compactMap { element -> String? in
+        return subpaths(atPath: absolutePath)?.parallelCompactMap { element -> String? in
             guard element.bridge().isSwiftFile() else { return nil }
             let absoluteElementPath = absolutePath.bridge().appendingPathComponent(element)
             return absoluteElementPath.isFile ? absoluteElementPath : nil

diff --git a/Source/SwiftLintFramework/Models/Linter.swift b/Source/SwiftLintFramework/Models/Linter.swift
@@ -126,7 +126,7 @@ public struct Linter {
         let superfluousDisableCommandRule = rules.first(where: {
             $0 is SuperfluousDisableCommandRule
         }) as? SuperfluousDisableCommandRule
-        let validationResults = rules.parallelFlatMap {
+        let validationResults = rules.parallelCompactMap {
             $0.lint(file: self.file, regions: regions, benchmark: benchmark,
                     superfluousDisableCommandRule: superfluousDisableCommandRule,
                     compilerArguments: self.compilerArguments)