Source: CompletionCommand.java 
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// distributed with this work for additional information
// regarding copyright ownership. The SFC licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License. You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
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// KIND, either express or implied. See the License for the
// specific language governing permissions and limitations
// under the License.
package org.openqa.selenium.grid.commands;
import com.beust.jcommander.JCommander;
import com.beust.jcommander.ParameterException;
import com.beust.jcommander.Parameters;
import com.beust.jcommander.internal.DefaultConsole;
import com.google.auto.service.AutoService;
import org.openqa.selenium.cli.CliCommand;
import org.openqa.selenium.grid.config.DescribedOption;
import org.openqa.selenium.grid.config.Role;
import org.openqa.selenium.grid.server.HelpFlags;
import java.io.PrintStream;
import java.util.AbstractMap;
import java.util.Collections;
import java.util.Comparator;
import java.util.Map;
import java.util.ServiceLoader;
import java.util.Set;
import java.util.stream.Collectors;
import java.util.stream.StreamSupport;
import static java.util.stream.Collectors.joining;
import static org.openqa.selenium.grid.config.StandardGridRoles.ALL_ROLES;
@AutoService(CliCommand.class)
public class CompletionCommand implements CliCommand {
@Override
public String getName() {
return "completion";
}
@Override
public String getDescription() {
return "Generate shell autocompletions";
}
@Override
public Set<Role> getConfigurableRoles() {
return ALL_ROLES;
}
@Override
public Set<Object> getFlagObjects() {
return Collections.singleton(new HelpFlags());
}
@Override
public Executable configure(PrintStream out, PrintStream err, String... args) {
HelpFlags help = new HelpFlags();
Zsh zsh = new Zsh();
JCommander commander = JCommander.newBuilder()
.programName("selenium")
.addObject(help)
.addCommand(zsh)
.build();
commander.setConsole(new DefaultConsole(out));
return () -> {
try {
commander.parse(args);
} catch (ParameterException e) {
err.println(e.getMessage());
commander.usage();
return;
}
if (help.displayHelp(commander, out)) {
return;
}
if (args.length == 0) {
commander.parse();
}
switch (commander.getParsedCommand()) {
case "zsh":
outputZshCompletions(out);
break;
default:
err.println("Unrecognised shell: " + commander.getParsedCommand());
System.exit(1);
break;
}
};
}
private void outputZshCompletions(PrintStream out) {
Map<CliCommand, Set<DescribedOption>> allCommands = listKnownCommands();
// My kingdom for multiline strings
out.println("#compdef selenium");
out.println("local context state state_descr line");
out.println("typeset -A opt_args");
out.println("_selenium() {");
out.println(" _arguments -C \\");
out.println(" '(- :)--ext[Amend the classpath for Grid]: :->arg' \\");
out.println(" '(-): :->command' \\");
out.println(" '(-)*:: :->arg' && return");
out.println(" case $state in");
out.println(" (command)");
out.println(" local cmds");
out.println(" cmds=(");
allCommands.keySet().stream()
.sorted(Comparator.comparing(CliCommand::getName))
.forEach(cmd -> {
out.println(String.format(" '%s:%s'", cmd.getName(), cmd.getDescription().replace("'", "\\'")));
});
out.println(" )");
out.println(" _describe 'commands' cmds");
out.println(" ;;");
out.println(" (arg)");
out.println(" case ${words[1]} in");
allCommands.keySet().stream()
.sorted(Comparator.comparing(CliCommand::getName))
.forEach(cmd -> {
String shellName = cmd.getName().replace('-', '_');
out.println(String.format(" (%s)", cmd.getName()));
out.println(String.format(" _selenium_%s", shellName));
out.println(" ;;");
});
out.println(" esac");
out.println(" ;;");
out.println(" esac");
out.println("}\n\n");
allCommands.forEach((cmd, options) -> {
out.println(String.format("_selenium_%s() {", cmd.getName().replace('-', '_')));
out.println(" args=(");
options.stream()
.filter(opt -> !opt.flags().isEmpty())
.sorted(Comparator.comparing(opt -> opt.flags().iterator().next()))
.forEach(opt -> {
String quotedDesc = opt.description.replace("'", "\\''").replace(":", "\\:");
if (opt.flags().size() == 1) {
out.println(String.format(" '%s[%s]%s'", opt.flags().iterator().next(), quotedDesc, getZshType(opt)));
} else {
out.print(" '");
out.print(opt.flags.stream().collect(joining(" ", "(", ")")));
out.print("'");
out.print(opt.flags.stream().collect(joining(",", "{", "}")));
out.print("'");
out.print(String.format("[%s]", quotedDesc));
out.print(getZshType(opt));
out.print("'\n");
}
});
out.println(" )");
out.println(" _arguments $args && return");
out.println("}\n\n");
});
out.println("_selenium");
}
private String getZshType(DescribedOption option) {
switch (option.type) {
case "boolean":
return ":(true false)";
case "int":
return ":int";
case "list of strings":
case "string":
return ": ";
case "uri":
case "url":
return ":urls: ";
case "path":
return ":filename:_files";
default:
throw new IllegalStateException("Unknown type: " + option.type);
}
}
private Map<CliCommand, Set<DescribedOption>> listKnownCommands() {
return StreamSupport.stream(ServiceLoader.load(CliCommand.class).spliterator(), true)
.map(command -> new AbstractMap.SimpleEntry<>(
command,
DescribedOption.findAllMatchingOptions(command.getConfigurableRoles())))
.collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));
}
@Parameters(commandNames = "zsh", commandDescription = "Create autocompletions for zsh")
private static class Zsh {}
}
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