src/main/java/com/google/devtools/common/options/OptionsUsage.java - bazel - Git at Google

 // 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.lang.reflect.Field;
 import java.text.BreakIterator;
 import java.util.ArrayList;
 import java.util.Comparator;
 import java.util.List;
 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<Field> optionFields = new ArrayList<>(data.getFieldsForClass(optionsClass));
     optionFields.sort(BY_NAME);
     for (Field optionField : optionFields) {
       getUsage(optionField, usage, OptionsParser.HelpVerbosity.LONG, data);
     }
   }

   /**
    * 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(
       Field optionField, OptionsData optionsData) {
     Preconditions.checkNotNull(optionField);
     Preconditions.checkNotNull(optionsData);
     try {
       return optionsData.getEvaluatedExpansion(optionField, null);
     } catch (ExpansionNeedsValueException e) {
       return null;
     } catch (OptionsParsingException e) {
       throw new IllegalStateException("Error expanding void expansion function: ", e);
     }

   }

   /** Appends the usage message for a single option-field message to 'usage'. */
   static void getUsage(
       Field optionField,
       StringBuilder usage,
       OptionsParser.HelpVerbosity helpVerbosity,
       OptionsData optionsData) {
     String flagName = getFlagName(optionField, optionsData);
     String typeDescription = getTypeDescription(optionField, optionsData);
     Option annotation = optionField.getAnnotation(Option.class);
     usage.append("  --").append(flagName);
     if (helpVerbosity == OptionsParser.HelpVerbosity.SHORT) { // just the name
       usage.append('\n');
       return;
     }
     if (annotation.abbrev() != '\0') {
       usage.append(" [-").append(annotation.abbrev()).append(']');
     }
     if (!typeDescription.equals("")) {
       usage.append(" (").append(typeDescription).append("; ");
       if (annotation.allowMultiple()) {
         usage.append("may be used multiple times");
       } else {
         // Don't call the annotation directly (we must allow overrides to certain defaults)
         String defaultValueString = OptionsParserImpl.getDefaultOptionString(optionField);
         if (OptionsParserImpl.isSpecialNullDefault(defaultValueString, optionField)) {
           usage.append("default: see description");
         } else {
           usage.append("default: \"").append(defaultValueString).append("\"");
         }
       }
       usage.append(")");
     }
     usage.append("\n");
     if (helpVerbosity == OptionsParser.HelpVerbosity.MEDIUM) { // just the name and type.
       return;
     }
     if (!annotation.help().equals("")) {
       usage.append(paragraphFill(annotation.help(), /*indent=*/ 4, /*width=*/ 80));
       usage.append('\n');
     }
     ImmutableList<String> expansion = getExpansionIfKnown(optionField, 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 (annotation.implicitRequirements().length > 0) {
       StringBuilder requiredMsg = new StringBuilder("Using this option will also add: ");
       for (String req : annotation.implicitRequirements()) {
         requiredMsg.append(req).append(" ");
       }
       usage.append(paragraphFill(requiredMsg.toString(), /*indent=*/ 6, /*width=*/ 80));
       usage.append('\n');
     }
   }

   /** Append the usage message for a single option-field message to 'usage'. */
   static void getUsageHtml(
       Field optionField, StringBuilder usage, Escaper escaper, OptionsData optionsData) {
     Option annotation = optionField.getAnnotation(Option.class);
     String plainFlagName = annotation.name();
     String flagName = getFlagName(optionField, optionsData);
     String valueDescription = annotation.valueHelp();
     String typeDescription = getTypeDescription(optionField, optionsData);
     usage.append("<dt><code><a name=\"flag--").append(plainFlagName).append("\"></a>--");
     usage.append(flagName);
     if (optionsData.isBooleanField(optionField) || OptionsData.isVoidField(optionField)) {
       // 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("=&lt;").append(escaper.escape(typeDescription)).append("&gt");
     }
     usage.append("</code>");
     if (annotation.abbrev() != '\0') {
       usage.append(" [<code>-").append(annotation.abbrev()).append("</code>]");
     }
     if (annotation.allowMultiple()) {
       // 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 = OptionsParserImpl.getDefaultOptionString(optionField);
       if (OptionsData.isVoidField(optionField)) {
         // Void options don't have a default.
       } else if (OptionsParserImpl.isSpecialNullDefault(defaultValueString, optionField)) {
         usage.append(" default: see description");
       } else {
         usage.append(" default: \"").append(escaper.escape(defaultValueString)).append("\"");
       }
     }
     usage.append("</dt>\n");
     usage.append("<dd>\n");
     if (!annotation.help().isEmpty()) {
       usage.append(paragraphFill(escaper.escape(annotation.help()), /*indent=*/ 0, /*width=*/ 80));
       usage.append('\n');
     }
     ImmutableList<String> expansion = getExpansionIfKnown(optionField, optionsData);
     if (expansion == null) {
       usage.append("    Expands to unknown options.<br>\n");
     } else if (!expansion.isEmpty()) {
       usage.append("<br/>\n");
       StringBuilder expandsMsg = new StringBuilder("Expands to:<br/>\n");
       for (String exp : expansion) {
         // TODO(ulfjack): Can we link to the expanded flags here?
         expandsMsg
             .append("&nbsp;&nbsp;<code>")
             .append(escaper.escape(exp))
             .append("</code><br/>\n");
       }
       usage.append(expandsMsg.toString());
       usage.append('\n');
     }
     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 field The field to return completion for
    * @param builder the string builder to store the completion values
    */
   static void getCompletion(Field field, StringBuilder builder) {
     // Return the list of possible completions for this option
     String flagName = field.getAnnotation(Option.class).name();
     Class<?> fieldType = field.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()).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");
     }
   }

   // TODO(brandjon): Should this use sorting by option name instead of field name?
   private static final Comparator<Field> BY_NAME = new Comparator<Field>() {
     @Override
     public int compare(Field left, Field right) {
       return left.getName().compareTo(right.getName());
     }
   };

   /**
    * An ordering relation for option-field fields that first groups together
    * options of the same category, then sorts by name within the category.
    */
   static final Comparator<Field> BY_CATEGORY = new Comparator<Field>() {
     @Override
     public int compare(Field left, Field right) {
       int r = left.getAnnotation(Option.class).category().compareTo(
               right.getAnnotation(Option.class).category());
       return r == 0 ? BY_NAME.compare(left, right) : r;
     }
   };

   private static String getTypeDescription(Field optionsField, OptionsData optionsData) {
     return optionsData.getConverter(optionsField).getTypeDescription();
   }

   static String getFlagName(Field field, OptionsData optionsData) {
     String name = field.getAnnotation(Option.class).name();
     return optionsData.isBooleanField(field) ? "[no]" + name : name;
   }

 }
	// 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.lang.reflect.Field;
	import java.text.BreakIterator;
	import java.util.ArrayList;
	import java.util.Comparator;
	import java.util.List;
	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<Field> optionFields = new ArrayList<>(data.getFieldsForClass(optionsClass));
	optionFields.sort(BY_NAME);
	for (Field optionField : optionFields) {
	getUsage(optionField, usage, OptionsParser.HelpVerbosity.LONG, data);
	}
	}

	/**
	* 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(
	Field optionField, OptionsData optionsData) {
	Preconditions.checkNotNull(optionField);
	Preconditions.checkNotNull(optionsData);
	try {
	return optionsData.getEvaluatedExpansion(optionField, null);
	} catch (ExpansionNeedsValueException e) {
	return null;
	} catch (OptionsParsingException e) {
	throw new IllegalStateException("Error expanding void expansion function: ", e);
	}

	}

	/** Appends the usage message for a single option-field message to 'usage'. */
	static void getUsage(
	Field optionField,
	StringBuilder usage,
	OptionsParser.HelpVerbosity helpVerbosity,
	OptionsData optionsData) {
	String flagName = getFlagName(optionField, optionsData);
	String typeDescription = getTypeDescription(optionField, optionsData);
	Option annotation = optionField.getAnnotation(Option.class);
	usage.append(" --").append(flagName);
	if (helpVerbosity == OptionsParser.HelpVerbosity.SHORT) { // just the name
	usage.append('\n');
	return;
	}
	if (annotation.abbrev() != '\0') {
	usage.append(" [-").append(annotation.abbrev()).append(']');
	}
	if (!typeDescription.equals("")) {
	usage.append(" (").append(typeDescription).append("; ");
	if (annotation.allowMultiple()) {
	usage.append("may be used multiple times");
	} else {
	// Don't call the annotation directly (we must allow overrides to certain defaults)
	String defaultValueString = OptionsParserImpl.getDefaultOptionString(optionField);
	if (OptionsParserImpl.isSpecialNullDefault(defaultValueString, optionField)) {
	usage.append("default: see description");
	} else {
	usage.append("default: \"").append(defaultValueString).append("\"");
	}
	}
	usage.append(")");
	}
	usage.append("\n");
	if (helpVerbosity == OptionsParser.HelpVerbosity.MEDIUM) { // just the name and type.
	return;
	}
	if (!annotation.help().equals("")) {
	usage.append(paragraphFill(annotation.help(), /indent=/ 4, /width=/ 80));
	usage.append('\n');
	}
	ImmutableList<String> expansion = getExpansionIfKnown(optionField, 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 (annotation.implicitRequirements().length > 0) {
	StringBuilder requiredMsg = new StringBuilder("Using this option will also add: ");
	for (String req : annotation.implicitRequirements()) {
	requiredMsg.append(req).append(" ");
	}
	usage.append(paragraphFill(requiredMsg.toString(), /indent=/ 6, /width=/ 80));
	usage.append('\n');
	}
	}

	/** Append the usage message for a single option-field message to 'usage'. */
	static void getUsageHtml(
	Field optionField, StringBuilder usage, Escaper escaper, OptionsData optionsData) {
	Option annotation = optionField.getAnnotation(Option.class);
	String plainFlagName = annotation.name();
	String flagName = getFlagName(optionField, optionsData);
	String valueDescription = annotation.valueHelp();
	String typeDescription = getTypeDescription(optionField, optionsData);
	usage.append("<dt><code><a name=\"flag--").append(plainFlagName).append("\"></a>--");
	usage.append(flagName);
	if (optionsData.isBooleanField(optionField) \|\| OptionsData.isVoidField(optionField)) {
	// 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("&gt");
	}
	usage.append("</code>");
	if (annotation.abbrev() != '\0') {
	usage.append(" [<code>-").append(annotation.abbrev()).append("</code>]");
	}
	if (annotation.allowMultiple()) {
	// 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 = OptionsParserImpl.getDefaultOptionString(optionField);
	if (OptionsData.isVoidField(optionField)) {
	// Void options don't have a default.
	} else if (OptionsParserImpl.isSpecialNullDefault(defaultValueString, optionField)) {
	usage.append(" default: see description");
	} else {
	usage.append(" default: \"").append(escaper.escape(defaultValueString)).append("\"");
	}
	}
	usage.append("</dt>\n");
	usage.append("<dd>\n");
	if (!annotation.help().isEmpty()) {
	usage.append(paragraphFill(escaper.escape(annotation.help()), /indent=/ 0, /width=/ 80));
	usage.append('\n');
	}
	ImmutableList<String> expansion = getExpansionIfKnown(optionField, optionsData);
	if (expansion == null) {
	usage.append(" Expands to unknown options.<br>\n");
	} else if (!expansion.isEmpty()) {
	usage.append("<br/>\n");
	StringBuilder expandsMsg = new StringBuilder("Expands to:<br/>\n");
	for (String exp : expansion) {
	// TODO(ulfjack): Can we link to the expanded flags here?
	expandsMsg
	.append("  <code>")
	.append(escaper.escape(exp))
	.append("</code><br/>\n");
	}
	usage.append(expandsMsg.toString());
	usage.append('\n');
	}
	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 field The field to return completion for
	* @param builder the string builder to store the completion values
	*/
	static void getCompletion(Field field, StringBuilder builder) {
	// Return the list of possible completions for this option
	String flagName = field.getAnnotation(Option.class).name();
	Class<?> fieldType = field.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()).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");
	}
	}

	// TODO(brandjon): Should this use sorting by option name instead of field name?
	private static final Comparator<Field> BY_NAME = new Comparator<Field>() {
	@Override
	public int compare(Field left, Field right) {
	return left.getName().compareTo(right.getName());
	}
	};

	/**
	* An ordering relation for option-field fields that first groups together
	* options of the same category, then sorts by name within the category.
	*/
	static final Comparator<Field> BY_CATEGORY = new Comparator<Field>() {
	@Override
	public int compare(Field left, Field right) {
	int r = left.getAnnotation(Option.class).category().compareTo(
	right.getAnnotation(Option.class).category());
	return r == 0 ? BY_NAME.compare(left, right) : r;
	}
	};

	private static String getTypeDescription(Field optionsField, OptionsData optionsData) {
	return optionsData.getConverter(optionsField).getTypeDescription();
	}

	static String getFlagName(Field field, OptionsData optionsData) {
	String name = field.getAnnotation(Option.class).name();
	return optionsData.isBooleanField(field) ? "[no]" + name : name;
	}

	}