Use Foundation Essentials when possible (#804)

* add implementation of replacing(_:with:)
* remove use of range(of:)
* Consolidate foundation usage
* Consolidate error to string logic
* Clean up env a bit

Author: rauhul

Sources/ArgumentParser/CMakeLists.txt

@@ -43,6 +43,7 @@ add_library(ArgumentParser
 
   Utilities/CollectionExtensions.swift
   Utilities/Mutex.swift
+  Utilities/Foundation.swift
   Utilities/Platform.swift
   Utilities/SequenceExtensions.swift
   Utilities/StringExtensions.swift

Sources/ArgumentParser/Completions/BashCompletionsGenerator.swift

@@ -190,10 +190,10 @@ extension CommandInfoV0 {
             shopt -s extglob
             set +o history +o posix
 
-            local -xr \(CompletionShell.shellEnvironmentVariableName)=bash
-            local -x \(CompletionShell.shellVersionEnvironmentVariableName)
-            \(CompletionShell.shellVersionEnvironmentVariableName)="$(IFS='.';printf %s "${BASH_VERSINFO[*]}")"
-            local -r \(CompletionShell.shellVersionEnvironmentVariableName)
+            local -xr \(Platform.Environment.Key.shellName.rawValue)=bash
+            local -x \(Platform.Environment.Key.shellVersion.rawValue)
+            \(Platform.Environment.Key.shellVersion.rawValue)="$(IFS='.';printf %s "${BASH_VERSINFO[*]}")"
+            local -r \(Platform.Environment.Key.shellVersion.rawValue)
 
             local -r cur="${2}"
             local -r prev="${3}"

Sources/ArgumentParser/Completions/CompletionsGenerator.swift

@@ -11,14 +11,14 @@
 
 #if compiler(>=6.0)
 internal import ArgumentParserToolInfo
-internal import Foundation
 #else
 import ArgumentParserToolInfo
-import Foundation
 #endif
 
 /// A shell for which the parser can generate a completion script.
-public struct CompletionShell: RawRepresentable, Hashable, CaseIterable {
+public struct CompletionShell: RawRepresentable, Hashable, CaseIterable,
+  Sendable
+{
   public var rawValue: String
 
   /// Creates a new instance from the given string.
@@ -87,20 +87,6 @@ public struct CompletionShell: RawRepresentable, Hashable, CaseIterable {
     Self._requestingVersion.withLock { $0 }
   }
 
-  /// The name of the environment variable whose value is the name of the shell
-  /// for which completions are being requested from a custom completion
-  /// handler.
-  ///
-  /// The environment variable is set in generated completion scripts.
-  static let shellEnvironmentVariableName = "SAP_SHELL"
-
-  /// The name of the environment variable whose value is the version of the
-  /// shell for which completions are being requested from a custom completion
-  /// handler.
-  ///
-  /// The environment variable is set in generated completion scripts.
-  static let shellVersionEnvironmentVariableName = "SAP_SHELL_VERSION"
-
   func format(completions: [String]) -> String {
     var completions = completions
     if self == .zsh {
@@ -157,12 +143,82 @@ extension String {
   func shellEscapeForSingleQuotedString(iterationCount: UInt64 = 1) -> Self {
     iterationCount == 0
       ? self
-      : replacingOccurrences(of: "'", with: "'\\''")
+      : self
+        .replacing("'", with: "'\\''")
         .shellEscapeForSingleQuotedString(iterationCount: iterationCount - 1)
   }
 
   func shellEscapeForVariableName() -> Self {
-    replacingOccurrences(of: "-", with: "_")
+    self.replacing("-", with: "_")
+  }
+
+  func replacing(_ old: Self, with new: Self) -> Self {
+    guard !old.isEmpty else { return self }
+
+    var result = ""
+    var startIndex = self.startIndex
+
+    // Look for occurrences of the old string.
+    while let matchRange = self.firstMatch(of: old, at: startIndex) {
+      // Add the substring before the match.
+      result.append(contentsOf: self[startIndex..<matchRange.start])
+
+      // Add the replacement string.
+      result.append(contentsOf: new)
+
+      // Move past the matched portion.
+      startIndex = matchRange.end
+    }
+
+    // No more matches found, add the rest of the string.
+    result.append(contentsOf: self[startIndex..<self.endIndex])
+
+    return result
+  }
+
+  func firstMatch(
+    of match: Self,
+    at startIndex: Self.Index
+  ) -> (start: Self.Index, end: Self.Index)? {
+    guard !match.isEmpty else { return nil }
+    guard match.count <= self.count else { return nil }
+
+    var startIndex = startIndex
+    while startIndex < self.endIndex {
+      // Check if theres a match.
+      if let endIndex = self.matches(match, at: startIndex) {
+        // Return the match.
+        return (startIndex, endIndex)
+      }
+
+      // Move to the next of index.
+      self.formIndex(after: &startIndex)
+    }
+
+    return nil
+  }
+
+  func matches(
+    _ match: Self,
+    at startIndex: Self.Index
+  ) -> Self.Index? {
+    var selfIndex = startIndex
+    var matchIndex = match.startIndex
+
+    while true {
+      // Only continue checking if there is more match to check
+      guard matchIndex < match.endIndex else { return selfIndex }
+
+      // Exit early if there is no more "self" to check.
+      guard selfIndex < self.endIndex else { return nil }
+
+      // Check match and self are the the same.
+      guard self[selfIndex] == match[matchIndex] else { return nil }
+
+      // Move to the next pair of indices.
+      self.formIndex(after: &selfIndex)
+      match.formIndex(after: &matchIndex)
+    }
   }
 }
 

Sources/ArgumentParser/Completions/FishCompletionsGenerator.swift

@@ -11,10 +11,8 @@
 
 #if compiler(>=6.0)
 internal import ArgumentParserToolInfo
-internal import Foundation
 #else
 import ArgumentParserToolInfo
-import Foundation
 #endif
 
 extension ToolInfoV0 {
@@ -75,8 +73,8 @@ extension CommandInfoV0 {
     end
 
     function \(customCompletionFunctionName)
-        set -x \(CompletionShell.shellEnvironmentVariableName) fish
-        set -x \(CompletionShell.shellVersionEnvironmentVariableName) $FISH_VERSION
+        set -x \(Platform.Environment.Key.shellName.rawValue) fish
+        set -x \(Platform.Environment.Key.shellVersion.rawValue) $FISH_VERSION
 
         set -l tokens (\(tokensFunctionName) -p)
         if test -z (\(tokensFunctionName) -t)
@@ -315,8 +313,9 @@ extension String {
   ) -> Self {
     iterationCount == 0
       ? self
-      : replacingOccurrences(of: "\\", with: "\\\\")
-        .replacingOccurrences(of: "'", with: "\\'")
+      : self
+        .replacing("\\", with: "\\\\")
+        .replacing("'", with: "\\'")
         .fishEscapeForSingleQuotedString(iterationCount: iterationCount - 1)
   }
 }

Sources/ArgumentParser/Completions/ZshCompletionsGenerator.swift

@@ -11,10 +11,8 @@
 
 #if compiler(>=6.0)
 internal import ArgumentParserToolInfo
-internal import Foundation
 #else
 import ArgumentParserToolInfo
-import Foundation
 #endif
 
 extension ToolInfoV0 {
@@ -111,10 +109,10 @@ extension CommandInfoV0 {
               setopt extendedglob nullglob numericglobsort
               unsetopt aliases banghist
 
-              local -xr \(CompletionShell.shellEnvironmentVariableName)=zsh
-              local -x \(CompletionShell.shellVersionEnvironmentVariableName)
-              \(CompletionShell.shellVersionEnvironmentVariableName)="$(builtin emulate zsh -c 'printf %s "${ZSH_VERSION}"')"
-              local -r \(CompletionShell.shellVersionEnvironmentVariableName)
+              local -xr \(Platform.Environment.Key.shellName.rawValue)=zsh
+              local -x \(Platform.Environment.Key.shellVersion.rawValue)
+              \(Platform.Environment.Key.shellVersion.rawValue)="$(builtin emulate zsh -c 'printf %s "${ZSH_VERSION}"')"
+              local -r \(Platform.Environment.Key.shellVersion.rawValue)
 
               local context state state_descr line
               local -A opt_args
@@ -271,19 +269,17 @@ extension ArgumentInfoV0 {
 
 extension String {
   fileprivate func zshEscapeForSingleQuotedDescribeCompletion() -> String {
-    replacingOccurrences(
-      of: #"[:\\]"#,
-      with: #"\\$0"#,
-      options: .regularExpression
-    )
-    .shellEscapeForSingleQuotedString()
+    self
+      .replacing("\\", with: "\\\\")
+      .replacing(":", with: "\\:")
+      .shellEscapeForSingleQuotedString()
   }
   fileprivate func zshEscapeForSingleQuotedOptionSpec() -> String {
-    replacingOccurrences(
-      of: #"[:\\\[\]]"#,
-      with: #"\\$0"#,
-      options: .regularExpression
-    )
-    .shellEscapeForSingleQuotedString()
+    self
+      .replacing("\\", with: "\\\\")
+      .replacing(":", with: "\\:")
+      .replacing("[", with: "\\[")
+      .replacing("]", with: "\\]")
+      .shellEscapeForSingleQuotedString()
   }
 }

Sources/ArgumentParser/Parsable Types/ParsableArguments.swift

@@ -9,12 +9,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-#if compiler(>=6.0)
-internal import Foundation
-#else
-import Foundation
-#endif
-
 /// A type that can be parsed from a program's command-line arguments.
 ///
 /// When you implement a `ParsableArguments` type, all properties must be declared with
@@ -41,13 +35,14 @@ struct _WrappedParsableCommand<P: ParsableArguments>: ParsableCommand {
 
     // If the type is named something like "TransformOptions", we only want
     // to use "transform" as the command name.
-    if let optionsRange = name.range(of: "_options"),
-      optionsRange.upperBound == name.endIndex
-    {
-      return String(name[..<optionsRange.lowerBound])
-    } else {
+    guard
+      let matchRange = name.firstMatch(of: "_options", at: name.startIndex),
+      matchRange.end == name.endIndex
+    else {
       return name
     }
+
+    return String(name[..<matchRange.start])
   }
 
   @OptionGroup var options: P

Sources/ArgumentParser/Parsing/ArgumentDefinition.swift

@@ -304,7 +304,8 @@ extension ArgumentDefinition {
     help: ArgumentHelp?,
     defaultValueDescription: String?,
     parsingStrategy: ParsingStrategy,
-    parser: @escaping (InputKey, InputOrigin, Name?, String) throws ->
+    parser:
+      @escaping (InputKey, InputOrigin, Name?, String) throws ->
       Container.Contained,
     initial: Container.Initial?,
     completion: CompletionKind?

Sources/ArgumentParser/Parsing/CommandParser.swift

@@ -13,14 +13,10 @@
 #if canImport(Dispatch)
 @preconcurrency private import class Dispatch.DispatchSemaphore
 #endif
-internal import class Foundation.NSLock
-internal import class Foundation.ProcessInfo
 #else
 #if canImport(Dispatch)
 @preconcurrency import class Dispatch.DispatchSemaphore
 #endif
-import class Foundation.NSLock
-import class Foundation.ProcessInfo
 #endif
 
 struct CommandError: Error {
@@ -455,16 +451,13 @@ extension CommandParser {
     _ argument: ArgumentDefinition,
     forArguments args: [String]
   ) throws {
-    let environment = ProcessInfo.processInfo.environment
-    if let completionShellName = environment[
-      CompletionShell.shellEnvironmentVariableName]
-    {
+    if let completionShellName = Platform.Environment[.shellName] {
       let shell = CompletionShell(rawValue: completionShellName)
       CompletionShell._requesting.withLock { $0 = shell }
     }
 
     CompletionShell._requestingVersion.withLock {
-      $0 = environment[CompletionShell.shellVersionEnvironmentVariableName]
+      $0 = Platform.Environment[.shellVersion]
     }
 
     let completions: [String]
@@ -550,46 +543,23 @@ private func asyncCustomCompletions(
   let (args, completingArgumentIndex, completingPrefix) =
     try parseCustomCompletionArguments(from: args)
 
-  let completionsBox = SendableBox<[String]>([])
+  let completionsBox = Mutex<[String]>([])
   let semaphore = DispatchSemaphore(value: 0)
 
   Task {
-    completionsBox.value = await complete(
+    let completion = await complete(
       args,
       completingArgumentIndex,
-      completingPrefix
-    )
+      completingPrefix)
+    completionsBox.withLock { $0 = completion }
     semaphore.signal()
   }
 
   semaphore.wait()
-  return completionsBox.value
+  return completionsBox.withLock { $0 }
   #endif
 }
 
-// Helper class to make values sendable across concurrency boundaries
-private final class SendableBox<T>: @unchecked Sendable {
-  private let lock = NSLock()
-  private var _value: T
-
-  init(_ value: T) {
-    self._value = value
-  }
-
-  var value: T {
-    get {
-      lock.lock()
-      defer { lock.unlock() }
-      return _value
-    }
-    set {
-      lock.lock()
-      defer { lock.unlock() }
-      _value = newValue
-    }
-  }
-}
-
 // MARK: Building Command Stacks
 
 extension CommandParser {

Sources/ArgumentParser/Usage/DumpHelpGenerator.swift

@@ -11,10 +11,8 @@
 
 #if compiler(>=6.0)
 internal import ArgumentParserToolInfo
-internal import class Foundation.JSONEncoder
 #else
 import ArgumentParserToolInfo
-import class Foundation.JSONEncoder
 #endif
 
 internal struct DumpHelpGenerator {
@@ -29,11 +27,7 @@ internal struct DumpHelpGenerator {
   }
 
   func rendered() -> String {
-    let encoder = JSONEncoder()
-    encoder.outputFormatting = .prettyPrinted
-    encoder.outputFormatting.insert(.sortedKeys)
-    guard let encoded = try? encoder.encode(self.toolInfo) else { return "" }
-    return String(data: encoded, encoding: .utf8) ?? ""
+    JSONEncoder.encode(self.toolInfo)
   }
 }