// Copyright 2014 The Bazel Authors. All rights reserved.
//
// Licensed 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 "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package com.google.devtools.common.options;
import com.google.common.base.Joiner;
import com.google.common.base.Preconditions;
import com.google.common.base.Splitter;
import com.google.common.base.Strings;
import com.google.common.collect.ImmutableList;
import com.google.common.escape.Escaper;
import java.text.BreakIterator;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Locale;
import java.util.stream.Collectors;
import java.util.stream.Stream;
import javax.annotation.Nullable;
/** A renderer for usage messages for any combination of options classes. */
class OptionsUsage {
private static final Splitter NEWLINE_SPLITTER = Splitter.on('\n');
private static final Joiner COMMA_JOINER = Joiner.on(",");
/**
* Given an options class, render the usage string into the usage, which is passed in as an
* argument. This will not include information about expansions for options using expansion
* functions (it would be unsafe to report this as we cannot know what options from other {@link
* OptionsBase} subclasses they depend on until a complete parser is constructed).
*/
static void getUsage(Class<? extends OptionsBase> optionsClass, StringBuilder usage) {
OptionsData data = OptionsParser.getOptionsDataInternal(optionsClass);
List<OptionDefinition> optionDefinitions =
new ArrayList<>(OptionsData.getAllOptionDefinitionsForClass(optionsClass));
optionDefinitions.sort(OptionDefinition.BY_OPTION_NAME);
for (OptionDefinition optionDefinition : optionDefinitions) {
getUsage(optionDefinition, usage, OptionsParser.HelpVerbosity.LONG, data, false);
}
}
/**
* Paragraph-fill the specified input text, indenting lines to 'indent' and
* wrapping lines at 'width'. Returns the formatted result.
*/
static String paragraphFill(String in, int indent, int width) {
String indentString = Strings.repeat(" ", indent);
StringBuilder out = new StringBuilder();
String sep = "";
for (String paragraph : NEWLINE_SPLITTER.split(in)) {
// TODO(ccalvarin) break iterators expect hyphenated words to be line-breakable, which looks
// funny for --flag
BreakIterator boundary = BreakIterator.getLineInstance(); // (factory)
boundary.setText(paragraph);
out.append(sep).append(indentString);
int cursor = indent;
for (int start = boundary.first(), end = boundary.next();
end != BreakIterator.DONE;
start = end, end = boundary.next()) {
String word =
paragraph.substring(start, end); // (may include trailing space)
if (word.length() + cursor > width) {
out.append('\n').append(indentString);
cursor = indent;
}
out.append(word);
cursor += word.length();
}
sep = "\n";
}
return out.toString();
}
/**
* Returns the expansion for an option, if any, regardless of if the expansion is from a function
* or is statically declared in the annotation.
*/
private static @Nullable ImmutableList<String> getExpansionIfKnown(
OptionDefinition optionDefinition, OptionsData optionsData) {
Preconditions.checkNotNull(optionDefinition);
return optionsData.getEvaluatedExpansion(optionDefinition);
}
// Placeholder tag "UNKNOWN" is ignored.
private static boolean shouldEffectTagBeListed(OptionEffectTag effectTag) {
return !effectTag.equals(OptionEffectTag.UNKNOWN);
}
// Tags that only apply to undocumented options are excluded.
private static boolean shouldMetadataTagBeListed(OptionMetadataTag metadataTag) {
return !metadataTag.equals(OptionMetadataTag.HIDDEN)
&& !metadataTag.equals(OptionMetadataTag.INTERNAL);
}
/** Appends the usage message for a single option-field message to 'usage'. */
static void getUsage(
OptionDefinition optionDefinition,
StringBuilder usage,
OptionsParser.HelpVerbosity helpVerbosity,
OptionsData optionsData,
boolean includeTags) {
String flagName = getFlagName(optionDefinition);
String typeDescription = getTypeDescription(optionDefinition);
usage.append(" --").append(flagName);
if (helpVerbosity == OptionsParser.HelpVerbosity.SHORT) {
usage.append('\n');
return;
}
// Add the option's type and default information. Stop there for "medium" verbosity.
if (optionDefinition.getAbbreviation() != '\0') {
usage.append(" [-").append(optionDefinition.getAbbreviation()).append(']');
}
if (!typeDescription.equals("")) {
usage.append(" (").append(typeDescription).append("; ");
if (optionDefinition.allowsMultiple()) {
usage.append("may be used multiple times");
} else {
// Don't call the annotation directly (we must allow overrides to certain defaults)
String defaultValueString = optionDefinition.getUnparsedDefaultValue();
if (optionDefinition.isSpecialNullDefault()) {
usage.append("default: see description");
} else {
usage.append("default: \"").append(defaultValueString).append("\"");
}
}
usage.append(")");
}
usage.append("\n");
if (helpVerbosity == OptionsParser.HelpVerbosity.MEDIUM) {
return;
}
// For verbosity "long," add the full description and expansion, along with the tag
// information if requested.
if (!optionDefinition.getHelpText().isEmpty()) {
usage.append(paragraphFill(optionDefinition.getHelpText(), /*indent=*/ 4, /*width=*/ 80));
usage.append('\n');
}
ImmutableList<String> expansion = getExpansionIfKnown(optionDefinition, optionsData);
if (expansion == null) {
usage.append(paragraphFill("Expands to unknown options.", /*indent=*/ 6, /*width=*/ 80));
usage.append('\n');
} else if (!expansion.isEmpty()) {
StringBuilder expandsMsg = new StringBuilder("Expands to: ");
for (String exp : expansion) {
expandsMsg.append(exp).append(" ");
}
usage.append(paragraphFill(expandsMsg.toString(), /*indent=*/ 6, /*width=*/ 80));
usage.append('\n');
}
if (optionDefinition.hasImplicitRequirements()) {
StringBuilder requiredMsg = new StringBuilder("Using this option will also add: ");
for (String req : optionDefinition.getImplicitRequirements()) {
requiredMsg.append(req).append(" ");
}
usage.append(paragraphFill(requiredMsg.toString(), 6, 80)); // (indent, width)
usage.append('\n');
}
if (!includeTags) {
return;
}
// If we are expected to include the tags, add them for high verbosity.
Stream<OptionEffectTag> effectTagStream =
Arrays.stream(optionDefinition.getOptionEffectTags())
.filter(OptionsUsage::shouldEffectTagBeListed);
Stream<OptionMetadataTag> metadataTagStream =
Arrays.stream(optionDefinition.getOptionMetadataTags())
.filter(OptionsUsage::shouldMetadataTagBeListed);
String tagList =
Stream.concat(effectTagStream, metadataTagStream)
.map(tag -> tag.toString().toLowerCase())
.collect(Collectors.joining(", "));
if (!tagList.isEmpty()) {
usage.append(paragraphFill("Tags: " + tagList, 6, 80)); // (indent, width)
usage.append("\n");
}
}
/** Append the usage message for a single option-field message to 'usage'. */
static void getUsageHtml(
OptionDefinition optionDefinition,
StringBuilder usage,
Escaper escaper,
OptionsData optionsData,
boolean includeTags) {
String plainFlagName = optionDefinition.getOptionName();
String flagName = getFlagName(optionDefinition);
String valueDescription = optionDefinition.getValueTypeHelpText();
String typeDescription = getTypeDescription(optionDefinition);
usage.append("<dt><code><a name=\"flag--").append(plainFlagName).append("\"></a>--");
usage.append(flagName);
if (optionDefinition.usesBooleanValueSyntax() || optionDefinition.isVoidField()) {
// Nothing for boolean, tristate, boolean_or_enum, or void options.
} else if (!valueDescription.isEmpty()) {
usage.append("=").append(escaper.escape(valueDescription));
} else if (!typeDescription.isEmpty()) {
// Generic fallback, which isn't very good.
usage.append("=<").append(escaper.escape(typeDescription)).append(">");
}
usage.append("</code>");
if (optionDefinition.getAbbreviation() != '\0') {
usage.append(" [<code>-").append(optionDefinition.getAbbreviation()).append("</code>]");
}
if (optionDefinition.allowsMultiple()) {
// Allow-multiple options can't have a default value.
usage.append(" multiple uses are accumulated");
} else {
// Don't call the annotation directly (we must allow overrides to certain defaults).
String defaultValueString = optionDefinition.getUnparsedDefaultValue();
if (optionDefinition.isVoidField()) {
// Void options don't have a default.
} else if (optionDefinition.isSpecialNullDefault()) {
usage.append(" default: see description");
} else {
usage.append(" default: \"").append(escaper.escape(defaultValueString)).append("\"");
}
}
usage.append("</dt>\n");
usage.append("<dd>\n");
if (!optionDefinition.getHelpText().isEmpty()) {
usage.append(
paragraphFill(
escaper.escape(optionDefinition.getHelpText()), /*indent=*/ 0, /*width=*/ 80));
usage.append('\n');
}
if (!optionsData.getEvaluatedExpansion(optionDefinition).isEmpty()) {
// If this is an expansion option, list the expansion if known, or at least specify that we
// don't know.
usage.append("<br/>\n");
ImmutableList<String> expansion = getExpansionIfKnown(optionDefinition, optionsData);
StringBuilder expandsMsg;
if (expansion == null) {
expandsMsg = new StringBuilder("Expands to unknown options.<br/>\n");
} else {
Preconditions.checkArgument(!expansion.isEmpty());
expandsMsg = new StringBuilder("Expands to:<br/>\n");
for (String exp : expansion) {
// TODO(ulfjack): We should link to the expanded flags, but unfortunately we don't
// currently guarantee that all flags are only printed once. A flag in an OptionBase that
// is included by 2 different commands, but not inherited through a parent command, will
// be printed multiple times.
expandsMsg
.append(" <code>")
.append(escaper.escape(exp))
.append("</code><br/>\n");
}
}
usage.append(expandsMsg.toString());
}
// Add effect tags, if not UNKNOWN, and metadata tags, if not empty.
if (includeTags) {
Stream<OptionEffectTag> effectTagStream =
Arrays.stream(optionDefinition.getOptionEffectTags())
.filter(OptionsUsage::shouldEffectTagBeListed);
Stream<OptionMetadataTag> metadataTagStream =
Arrays.stream(optionDefinition.getOptionMetadataTags())
.filter(OptionsUsage::shouldMetadataTagBeListed);
String tagList =
Stream.concat(
effectTagStream.map(
tag ->
String.format(
"<a href=\"#effect_tag_%s\"><code>%s</code></a>",
tag, tag.name().toLowerCase())),
metadataTagStream.map(
tag ->
String.format(
"<a href=\"#metadata_tag_%s\"><code>%s</code></a>",
tag, tag.name().toLowerCase())))
.collect(Collectors.joining(", "));
if (!tagList.isEmpty()) {
usage.append("<br>Tags: \n").append(tagList);
}
}
usage.append("</dd>\n");
}
/**
* Returns the available completion for the given option field. The completions are the exact
* command line option (with the prepending '--') that one should pass. It is suitable for
* completion script to use. If the option expect an argument, the kind of argument is given
* after the equals. If the kind is a enum, the various enum values are given inside an accolade
* in a comma separated list. For other special kind, the type is given as a name (e.g.,
* <code>label</code>, <code>float</ode>, <code>path</code>...). Example outputs of this
* function are for, respectively, a tristate flag <code>tristate_flag</code>, a enum
* flag <code>enum_flag</code> which can take <code>value1</code>, <code>value2</code> and
* <code>value3</code>, a path fragment flag <code>path_flag</code>, a string flag
* <code>string_flag</code> and a void flag <code>void_flag</code>:
* <pre>
* --tristate_flag={auto,yes,no}
* --notristate_flag
* --enum_flag={value1,value2,value3}
* --path_flag=path
* --string_flag=
* --void_flag
* </pre>
*
* @param optionDefinition The field to return completion for
* @param builder the string builder to store the completion values
*/
static void getCompletion(OptionDefinition optionDefinition, StringBuilder builder) {
// Return the list of possible completions for this option
String flagName = optionDefinition.getOptionName();
Class<?> fieldType = optionDefinition.getType();
builder.append("--").append(flagName);
if (fieldType.equals(boolean.class)) {
builder.append("\n");
builder.append("--no").append(flagName).append("\n");
} else if (fieldType.equals(TriState.class)) {
builder.append("={auto,yes,no}\n");
builder.append("--no").append(flagName).append("\n");
} else if (fieldType.isEnum()) {
builder
.append("={")
.append(COMMA_JOINER.join(fieldType.getEnumConstants()).toLowerCase(Locale.ENGLISH))
.append("}\n");
} else if (fieldType.getSimpleName().equals("Label")) {
// String comparison so we don't introduce a dependency to com.google.devtools.build.lib.
builder.append("=label\n");
} else if (fieldType.getSimpleName().equals("PathFragment")) {
builder.append("=path\n");
} else if (Void.class.isAssignableFrom(fieldType)) {
builder.append("\n");
} else {
// TODO(bazel-team): add more types. Maybe even move the completion type
// to the @Option annotation?
builder.append("=\n");
}
}
private static String getTypeDescription(OptionDefinition optionsDefinition) {
return optionsDefinition.getConverter().getTypeDescription();
}
static String getFlagName(OptionDefinition optionDefinition) {
String name = optionDefinition.getOptionName();
return optionDefinition.usesBooleanValueSyntax() ? "[no]" + name : name;
}
}