Improve handling of special characters in file paths

Fixes #10

tmignore/Git.swift

@@ -10,16 +10,19 @@ class Git {
 		var ignoredFiles = [String]()
 
 		// Let Git list all ignored files/directories
-		// "-C [repoPath]": Directory to run the command in
-		// "--directory": If entire directory is ignored, only list its name (instead of all contained
-		// files)
-		// "--exclude-standard": Also use `.git/info/exclude` and the global `.gitignore` file
-		// "--ignored": List ignored files
-		// "--others": Include untracked files
-		// "-z": Do not encode "unusual" characters (e.g. "ä" is normally listed as "\303\244")
 		do {
-			let result = try execBash(
-				"git -C '\(repoPath)' ls-files --directory --exclude-standard --ignored --others -z"
+			let result = try exec(
+				program: "/usr/bin/git",
+				arguments: [
+					"-C", // Directory to run the command in
+					repoPath,
+					"ls-files",
+					"--directory", // Do not list contained files of ignored directories
+					"--exclude-standard", // Also use `.git/info/exclude` and global `.gitignore` files
+					"--ignored", // List ignored files
+					"--others", // Include untracked files
+					"-z", // Do not encode "unusual" characters (e.g. "ä" is normally listed as "\303\244")
+				]
 			)
 			// Split lines at NUL bytes (output by Git instead of newline characters because of the "-z"
 			// flag)
@@ -43,23 +46,23 @@ class Git {
 		logger.info("Searching for Git repositories in \(searchPath)…")
 
 		// Start building array of arguments for the `find` command
-		var command = "find \"\(searchPath)\""
+		var arguments = [searchPath]
 
 		// Tell `find` to skip the ignored paths
 		for ignoredPath in ignoredPaths {
-			command += " -path \(ignoredPath) -prune -o"
+			arguments += ["-path", ignoredPath, "-prune", "-o"]
 		}
 
 		// Add the remaining `find` arguments
 		// "-type d": Only search directories
 		// "-name .git": Only search for files/directories named ".git"
 		// "-print": Print the results
-		command += " -type d -name .git -print"
+		arguments += ["-type", "d", "-name", ".git", "-print"]
 
 		// Run the `find` command
 		var result: ExecResult
 		do {
-			result = try execBash(command)
+			result = try exec(program: "/usr/bin/find", arguments: arguments)
 		} catch {
 			let error = error as! ExecError
 			result = error.execResult

tmignore/TimeMachine.swift

@@ -4,22 +4,7 @@ import SwiftExec
 /// Class for modifying the list of files/directories which should be excluded from Time Machine
 /// backups
 class TimeMachine {
-	/// Takes the (potentially long) list of paths and splits it up into smaller chunks. Each chunk is
-	/// converted to a string of the form "'path1' 'path2' 'path3'" so these paths can be passed as
-	/// command arguments. The chunking is necessary because a size limit for shell commands exists
-	private static func buildArgStrs(paths: [String]) -> [String] {
-		let chunkSize = 200
-		var idx = 0
-		var argList = [String]()
-
-		while idx < paths.count {
-			let chunk = paths[idx ..< min(idx + chunkSize, paths.count - 1)]
-			argList.append(chunk.map { "'\($0)'" }.joined(separator: " "))
-			idx += chunkSize
-		}
-
-		return argList
-	}
+	static let chunkSize = 200
 
 	/// Adds the provided path to the list of exclusions (it will not be included in future backups)
 	static func addExclusions(paths: [String]) {
@@ -30,9 +15,9 @@ class TimeMachine {
 
 		logger.info("Adding backup exclusions for \(paths.count) paths…")
 
-		for argStr in buildArgStrs(paths: paths) {
+		for pathChunk in paths.chunked(by: chunkSize) {
 			do {
-				_ = try execBash("tmutil addexclusion \(argStr)")
+				_ = try exec(program: "/usr/bin/tmutil", arguments: ["addexclusion"] + pathChunk)
 			} catch {
 				let error = error as! ExecError
 				logger.error("Failed to add backup exclusions: \(error.execResult.stderr ?? "")")
@@ -52,9 +37,9 @@ class TimeMachine {
 
 		logger.info("Removing backup exclusions for \(paths.count) paths…")
 
-		for argStr in buildArgStrs(paths: paths) {
+		for pathChunk in paths.chunked(by: chunkSize) {
 			do {
-				_ = try execBash("tmutil removeexclusion \(argStr)")
+				_ = try exec(program: "/usr/bin/tmutil", arguments: ["removeexclusion"] + pathChunk)
 			} catch {
 				let error = error as! ExecError
 				// 213: File path wasn't found and could therefore not be excluded from a Time Machine

tmignore/utils.swift

@@ -1,6 +1,17 @@
 import Darwin
 import Foundation
 
+extension Array {
+	/// Splits the array into smaller chunks.
+	///
+	/// Source: https://stackoverflow.com/a/38156873/6767508
+	func chunked(by chunkSize: Int) -> [[Element]] {
+		stride(from: 0, to: count, by: chunkSize).map {
+			Array(self[$0 ..< Swift.min($0 + chunkSize, self.count)])
+		}
+	}
+}
+
 /// Calculates the added and removed elements between two versions of a list (V1 and V2)
 func findDiff(
 	elementsV1: [String],