Add support for uninstall/zap :trash.

Library/Homebrew/cask/lib/hbc/artifact/uninstall_base.rb

@@ -224,9 +224,14 @@ def uninstall_delete(*paths)
       end
 
       def uninstall_trash(*paths)
-        # :trash functionality is stubbed as a synonym for :delete
-        # TODO: make :trash work differently, moving files to the Trash
-        uninstall_delete(*paths)
+        return if paths.empty?
+
+        ohai "Trashing files:"
+        each_resolved_path(:trash, paths) do |path, resolved_paths|
+          puts path
+          resolved_paths.each { |resolved_path| Utils.gain_permissions(resolved_path, ["-R"], @command) }
+          @command.run!("/usr/bin/xargs", args: ["-0", "--", HOMEBREW_LIBRARY_PATH/"utils/trash.swift"], input: resolved_paths.join("\0"))
+        end
       end
 
       def uninstall_rmdir(*directories)

Library/Homebrew/test/utils/trash_spec.rb

@@ -0,0 +1,32 @@
+require "open3"
+
+describe "trash", :needs_macos do
+  let(:executable) { HOMEBREW_LIBRARY_PATH/"utils/trash.swift" }
+  let(:dir) { mktmpdir }
+  let(:file) { dir/"new_file" }
+
+  it "moves existing files to the trash" do
+    FileUtils.touch file
+
+    expect(file).to exist
+
+    out, err, status = Open3.capture3(executable, file)
+
+    expect(out).to match %r{moved #{file} to .*/\.Trash/\.*}
+    expect(err).to be_empty
+    expect(status).to be_a_success
+
+    expect(file).not_to exist
+
+    trashed_path = out.sub(/^moved #{Regexp.escape(file.to_s)} to (.*)\n$/, '\1')
+    FileUtils.rm_f trashed_path
+  end
+
+  it "fails when files don't exist" do
+    out, err, status = Open3.capture3(executable, file)
+
+    expect(out).to be_empty
+    expect(err).to eq "could not move #{file} to trash\n"
+    expect(status).to be_a_failure
+  end
+end

Library/Homebrew/utils/trash.swift

@@ -0,0 +1,43 @@
+#!/usr/bin/swift
+
+import Cocoa
+
+DispatchQueue.main.async {
+  let arguments = CommandLine.arguments.dropFirst().filter { !$0.isEmpty }
+  let URLs = arguments.map { URL(fileURLWithPath: $0) }
+
+  #if swift(>=4.0)
+  let workspace = NSWorkspace.shared
+  #else
+  let workspace = NSWorkspace.shared()
+  #endif
+
+  workspace.recycle(URLs) { (dict, error) in
+    dict.forEach {
+      #if swift(>=4.0)
+      let originalPath = $0.0.path
+      let trashPath    = $0.1.path
+      #else
+      let originalPath = $0.path
+      let trashPath    = $1.path
+      #endif
+
+      print("moved \(originalPath) to \(trashPath)")
+    }
+
+    if error == nil {
+      exit(0)
+    }
+
+    let trashedURLs = dict.keys
+    let untrashedURLs = URLs.filter { !trashedURLs.contains($0) }
+
+    untrashedURLs.forEach {
+      fputs("could not move \($0.path) to trash\n", stderr)
+    }
+
+    exit(1)
+  }
+}
+
+RunLoop.main.run()