src/main/java/com/google/devtools/build/lib/query2/query/output/BuildOutputFormatter.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.build.lib.query2.query.output;

 import com.google.common.base.Ascii;
 import com.google.common.collect.Iterables;
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.collect.compacthashset.CompactHashSet;
 import com.google.devtools.build.lib.packages.Attribute;
 import com.google.devtools.build.lib.packages.BuildType;
 import com.google.devtools.build.lib.packages.LabelPrinter;
 import com.google.devtools.build.lib.packages.License;
 import com.google.devtools.build.lib.packages.RawAttributeMapper;
 import com.google.devtools.build.lib.packages.Rule;
 import com.google.devtools.build.lib.packages.Target;
 import com.google.devtools.build.lib.packages.TriState;
 import com.google.devtools.build.lib.query2.engine.OutputFormatterCallback;
 import com.google.devtools.build.lib.query2.engine.QueryEnvironment;
 import com.google.devtools.build.lib.query2.engine.SynchronizedDelegatingOutputFormatterCallback;
 import com.google.devtools.build.lib.query2.engine.ThreadSafeOutputFormatterCallback;
 import java.io.IOException;
 import java.io.OutputStream;
 import java.io.Writer;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Set;
 import java.util.function.BiPredicate;
 import net.starlark.java.eval.Printer;
 import net.starlark.java.eval.StarlarkThread;

 /**
  * An output formatter that prints the generating rules using the syntax of the BUILD files. If
  * multiple targets are generated by the same rule, it is printed only once.
  */
 public class BuildOutputFormatter extends AbstractUnorderedFormatter {

   /**
    * Generic interface for determining the possible values for a given attribute on a given rule, as
    * precisely as the implementation knows. For example, cquery knows which branch a <code>select
    * </code> takes, while query doesn't.
    */
   public interface AttributeReader {
     Iterable<Object> getPossibleValues(Rule rule, Attribute attr);
   }

   /**
    * Generic logic for formatting a target BUILD-style.
    *
    * <p>This logic is implementation-agnostic. So it can be shared across query, cquery, and other
    * implementations.
    */
   public static class TargetOutputter {
     private final Writer writer;
     private final BiPredicate<Rule, Attribute> preserveSelect;
     private final String lineTerm;
     private final LabelPrinter labelPrinter;
     private final Set<Label> printed = CompactHashSet.create();

     /**
      * @param writer where to write output
      * @param preserveSelect a predicate that determines if the given attribute on the given rule is
      *     a <code>select</code> that should be output as-is (without figuring out which branch it
      *     takes). This is useful for implementations that can't evaluate <code>select</code>.
      * @param lineTerm character to add to the end of each line
      */
     public TargetOutputter(
         Writer writer,
         BiPredicate<Rule, Attribute> preserveSelect,
         String lineTerm,
         LabelPrinter labelPrinter) {
       this.writer = writer;
       this.preserveSelect = preserveSelect;
       this.lineTerm = lineTerm;
       this.labelPrinter = labelPrinter;
     }

     /** Outputs a given target in BUILD-style syntax. */
     public void output(Target target, AttributeReader attrReader) throws IOException {
       Rule rule = target.getAssociatedRule();
       if (rule == null || printed.contains(rule.getLabel())) {
         return;
       }
       outputRule(rule, attrReader, writer);
       printed.add(rule.getLabel());
     }

     /** Outputs a given rule in BUILD-style syntax. Made visible for Modquery command. */
     public void outputRule(Rule rule, AttributeReader attrReader, Writer writer)
         throws IOException {
       // TODO(b/151151653): display the filenames in root-relative form.
       // This is an incompatible change, but Blaze users (and their editors)
       // must already be equipped to handle relative paths as all compiler
       // error messages are execroot-relative.

       writer.append("# ").append(rule.getLocation().toString()).append(lineTerm);
       writer.append(rule.getRuleClass()).append("(").append(lineTerm);
       writer.append("  name = \"").append(rule.getName()).append("\",").append(lineTerm);

       for (Attribute attr : rule.getAttributes()) {
         // Ignore the "name" attribute here, as we already print it above.
         // This is not strictly necessary, but convention has it that the
         // name attribute is printed first.
         if ("name".equals(attr.getName())) {
           continue;
         }
         if (preserveSelect.test(rule, attr)) {
           writer
               .append("  ")
               .append(attr.getPublicName())
               .append(" = ")
               .append(reconstructSelect(rule, attr))
               .append(",")
               .append(lineTerm);
           continue;
         }
         AttributeValueSource attributeValueSource =
             AttributeValueSource.forRuleAndAttribute(rule, attr);
         if (attributeValueSource != AttributeValueSource.RULE) {
           continue; // Don't print default values.
         }

         Iterable<Object> values = attrReader.getPossibleValues(rule, attr);
         if (Iterables.size(values) != 1) {
           // Computed defaults that depend on configurable attributes can have multiple values.
           continue;
         }
         writer
             .append("  ")
             .append(attr.getPublicName())
             .append(" = ")
             .append(outputRawAttrValue(Iterables.getOnlyElement(values)))
             .append(",")
             .append(lineTerm);
       }
       writer.append(")").append(lineTerm);

       // Display the instantiation stack, if any.
       appendStack(
           String.format("# Rule %s instantiated at (most recent call last):", rule.getName()),
           rule.getCallStack().toList());

       // Display the stack of the rule class definition, if any.
       appendStack(
           String.format("# Rule %s defined at (most recent call last):", rule.getRuleClass()),
           rule.getRuleClassObject().getCallStack());

       // TODO(adonovan): also list inputs and outputs of the rule.

       writer.append(lineTerm);
     }

     private void appendStack(String title, List<StarlarkThread.CallStackEntry> stack)
         throws IOException {
       // For readability, ensure columns line up.
       int maxLocLen = 0;
       for (StarlarkThread.CallStackEntry fr : stack) {
         maxLocLen = Math.max(maxLocLen, fr.location.toString().length());
       }
       if (maxLocLen > 0) {
         writer.append(title).append(lineTerm);
         for (StarlarkThread.CallStackEntry fr : stack) {
           String loc = fr.location.toString(); // TODO(b/151151653): display root-relative
           // Java's String.format doesn't support
           // right-padding with %*s, so we must loop.
           writer.append("#   ").append(loc);
           for (int i = loc.length(); i < maxLocLen; i++) {
             writer.append(' ');
           }
           writer.append(" in ").append(fr.name).append(lineTerm);
         }
       }
     }

     /** Outputs the given attribute value BUILD-style. Does not support selects. */
     private String outputRawAttrValue(Object value) {
       if (value instanceof License) {
         List<String> licenseTypes = new ArrayList<>();
         for (License.LicenseType licenseType : ((License) value).getLicenseTypes()) {
           licenseTypes.add(Ascii.toLowerCase(licenseType.toString()));
         }
         value = licenseTypes;
       } else if (value instanceof TriState) {
         value = ((TriState) value).toInt();
       }
       return new Printer() {
         // Print labels in their canonical form.
         @Override
         public Printer repr(Object o) {
           return super.repr(o instanceof Label ? labelPrinter.toString((Label) o) : o);
         }
       }.repr(value).toString();
     }

     /**
      * Outputs a <code>select</code> BUILD-style without trying to resolve which branch it takes.
      */
     private String reconstructSelect(Rule rule, Attribute attr) {
       List<String> selectors = new ArrayList<>();
       RawAttributeMapper attributeMap = RawAttributeMapper.of(rule);
       for (BuildType.Selector<?> selector :
           ((BuildType.SelectorList<?>) attributeMap.getRawAttributeValue(rule, attr))
               .getSelectors()) {
         if (selector.isUnconditional()) {
           selectors.add(
               outputRawAttrValue(
                   Iterables.getOnlyElement(selector.getEntries().entrySet()).getValue()));
         } else {
           selectors.add(String.format("select(%s)", outputRawAttrValue(selector.getEntries())));
         }
       }
       return String.join(" + ", selectors);
     }
   }

   /** Query's implementation. */
   @Override
   public OutputFormatterCallback<Target> createPostFactoStreamCallback(
       OutputStream out, final QueryOptions options, LabelPrinter labelPrinter) {
     return new BuildOutputFormatterCallback(out, options.getLineTerminator(), labelPrinter);
   }

   @Override
   public ThreadSafeOutputFormatterCallback<Target> createStreamCallback(
       OutputStream out, QueryOptions options, QueryEnvironment<?> env) {
     return new SynchronizedDelegatingOutputFormatterCallback<>(
         createPostFactoStreamCallback(out, options, env.getLabelPrinter()));
   }

   /** BuildOutputFormatter callback for Query. Made visible for ModQuery. */
   public static class BuildOutputFormatterCallback extends TextOutputFormatterCallback<Target> {
     private final TargetOutputter targetOutputter;

     BuildOutputFormatterCallback(OutputStream out, String lineTerm, LabelPrinter labelPrinter) {
       super(out);
       this.targetOutputter =
           new TargetOutputter(
               writer,
               (rule, attr) -> RawAttributeMapper.of(rule).isConfigurable(attr.getName()),
               lineTerm,
               labelPrinter);
     }

     @Override
     public void processOutput(Iterable<Target> partialResult) throws IOException {
       for (Target target : partialResult) {
         targetOutputter.output(
             target,
             // Multiple possible values are ignored by the outputter.
             (rule, attr) ->
                 PossibleAttributeValues.forRuleAndAttribute(
                     rule, attr, /*mayTreatMultipleAsNone=*/ true));
       }
     }
   }

   @Override
   public String getName() {
     return "build";
   }
 }
	// 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.build.lib.query2.query.output;

	import com.google.common.base.Ascii;
	import com.google.common.collect.Iterables;
	import com.google.devtools.build.lib.cmdline.Label;
	import com.google.devtools.build.lib.collect.compacthashset.CompactHashSet;
	import com.google.devtools.build.lib.packages.Attribute;
	import com.google.devtools.build.lib.packages.BuildType;
	import com.google.devtools.build.lib.packages.LabelPrinter;
	import com.google.devtools.build.lib.packages.License;
	import com.google.devtools.build.lib.packages.RawAttributeMapper;
	import com.google.devtools.build.lib.packages.Rule;
	import com.google.devtools.build.lib.packages.Target;
	import com.google.devtools.build.lib.packages.TriState;
	import com.google.devtools.build.lib.query2.engine.OutputFormatterCallback;
	import com.google.devtools.build.lib.query2.engine.QueryEnvironment;
	import com.google.devtools.build.lib.query2.engine.SynchronizedDelegatingOutputFormatterCallback;
	import com.google.devtools.build.lib.query2.engine.ThreadSafeOutputFormatterCallback;
	import java.io.IOException;
	import java.io.OutputStream;
	import java.io.Writer;
	import java.util.ArrayList;
	import java.util.List;
	import java.util.Set;
	import java.util.function.BiPredicate;
	import net.starlark.java.eval.Printer;
	import net.starlark.java.eval.StarlarkThread;

	/**
	* An output formatter that prints the generating rules using the syntax of the BUILD files. If
	* multiple targets are generated by the same rule, it is printed only once.
	*/
	public class BuildOutputFormatter extends AbstractUnorderedFormatter {

	/**
	* Generic interface for determining the possible values for a given attribute on a given rule, as
	* precisely as the implementation knows. For example, cquery knows which branch a <code>select
	* </code> takes, while query doesn't.
	*/
	public interface AttributeReader {
	Iterable<Object> getPossibleValues(Rule rule, Attribute attr);
	}

	/**
	* Generic logic for formatting a target BUILD-style.
	*
	* <p>This logic is implementation-agnostic. So it can be shared across query, cquery, and other
	* implementations.
	*/
	public static class TargetOutputter {
	private final Writer writer;
	private final BiPredicate<Rule, Attribute> preserveSelect;
	private final String lineTerm;
	private final LabelPrinter labelPrinter;
	private final Set<Label> printed = CompactHashSet.create();

	/**
	* @param writer where to write output
	* @param preserveSelect a predicate that determines if the given attribute on the given rule is
	* a <code>select</code> that should be output as-is (without figuring out which branch it
	* takes). This is useful for implementations that can't evaluate <code>select</code>.
	* @param lineTerm character to add to the end of each line
	*/
	public TargetOutputter(
	Writer writer,
	BiPredicate<Rule, Attribute> preserveSelect,
	String lineTerm,
	LabelPrinter labelPrinter) {
	this.writer = writer;
	this.preserveSelect = preserveSelect;
	this.lineTerm = lineTerm;
	this.labelPrinter = labelPrinter;
	}

	/** Outputs a given target in BUILD-style syntax. */
	public void output(Target target, AttributeReader attrReader) throws IOException {
	Rule rule = target.getAssociatedRule();
	if (rule == null \|\| printed.contains(rule.getLabel())) {
	return;
	}
	outputRule(rule, attrReader, writer);
	printed.add(rule.getLabel());
	}

	/** Outputs a given rule in BUILD-style syntax. Made visible for Modquery command. */
	public void outputRule(Rule rule, AttributeReader attrReader, Writer writer)
	throws IOException {
	// TODO(b/151151653): display the filenames in root-relative form.
	// This is an incompatible change, but Blaze users (and their editors)
	// must already be equipped to handle relative paths as all compiler
	// error messages are execroot-relative.

	writer.append("# ").append(rule.getLocation().toString()).append(lineTerm);
	writer.append(rule.getRuleClass()).append("(").append(lineTerm);
	writer.append(" name = \"").append(rule.getName()).append("\",").append(lineTerm);

	for (Attribute attr : rule.getAttributes()) {
	// Ignore the "name" attribute here, as we already print it above.
	// This is not strictly necessary, but convention has it that the
	// name attribute is printed first.
	if ("name".equals(attr.getName())) {
	continue;
	}
	if (preserveSelect.test(rule, attr)) {
	writer
	.append(" ")
	.append(attr.getPublicName())
	.append(" = ")
	.append(reconstructSelect(rule, attr))
	.append(",")
	.append(lineTerm);
	continue;
	}
	AttributeValueSource attributeValueSource =
	AttributeValueSource.forRuleAndAttribute(rule, attr);
	if (attributeValueSource != AttributeValueSource.RULE) {
	continue; // Don't print default values.
	}

	Iterable<Object> values = attrReader.getPossibleValues(rule, attr);
	if (Iterables.size(values) != 1) {
	// Computed defaults that depend on configurable attributes can have multiple values.
	continue;
	}
	writer
	.append(" ")
	.append(attr.getPublicName())
	.append(" = ")
	.append(outputRawAttrValue(Iterables.getOnlyElement(values)))
	.append(",")
	.append(lineTerm);
	}
	writer.append(")").append(lineTerm);

	// Display the instantiation stack, if any.
	appendStack(
	String.format("# Rule %s instantiated at (most recent call last):", rule.getName()),
	rule.getCallStack().toList());

	// Display the stack of the rule class definition, if any.
	appendStack(
	String.format("# Rule %s defined at (most recent call last):", rule.getRuleClass()),
	rule.getRuleClassObject().getCallStack());

	// TODO(adonovan): also list inputs and outputs of the rule.

	writer.append(lineTerm);
	}

	private void appendStack(String title, List<StarlarkThread.CallStackEntry> stack)
	throws IOException {
	// For readability, ensure columns line up.
	int maxLocLen = 0;
	for (StarlarkThread.CallStackEntry fr : stack) {
	maxLocLen = Math.max(maxLocLen, fr.location.toString().length());
	}
	if (maxLocLen > 0) {
	writer.append(title).append(lineTerm);
	for (StarlarkThread.CallStackEntry fr : stack) {
	String loc = fr.location.toString(); // TODO(b/151151653): display root-relative
	// Java's String.format doesn't support
	// right-padding with %*s, so we must loop.
	writer.append("# ").append(loc);
	for (int i = loc.length(); i < maxLocLen; i++) {
	writer.append(' ');
	}
	writer.append(" in ").append(fr.name).append(lineTerm);
	}
	}
	}

	/** Outputs the given attribute value BUILD-style. Does not support selects. */
	private String outputRawAttrValue(Object value) {
	if (value instanceof License) {
	List<String> licenseTypes = new ArrayList<>();
	for (License.LicenseType licenseType : ((License) value).getLicenseTypes()) {
	licenseTypes.add(Ascii.toLowerCase(licenseType.toString()));
	}
	value = licenseTypes;
	} else if (value instanceof TriState) {
	value = ((TriState) value).toInt();
	}
	return new Printer() {
	// Print labels in their canonical form.
	@Override
	public Printer repr(Object o) {
	return super.repr(o instanceof Label ? labelPrinter.toString((Label) o) : o);
	}
	}.repr(value).toString();
	}

	/**
	* Outputs a <code>select</code> BUILD-style without trying to resolve which branch it takes.
	*/
	private String reconstructSelect(Rule rule, Attribute attr) {
	List<String> selectors = new ArrayList<>();
	RawAttributeMapper attributeMap = RawAttributeMapper.of(rule);
	for (BuildType.Selector<?> selector :
	((BuildType.SelectorList<?>) attributeMap.getRawAttributeValue(rule, attr))
	.getSelectors()) {
	if (selector.isUnconditional()) {
	selectors.add(
	outputRawAttrValue(
	Iterables.getOnlyElement(selector.getEntries().entrySet()).getValue()));
	} else {
	selectors.add(String.format("select(%s)", outputRawAttrValue(selector.getEntries())));
	}
	}
	return String.join(" + ", selectors);
	}
	}

	/** Query's implementation. */
	@Override
	public OutputFormatterCallback<Target> createPostFactoStreamCallback(
	OutputStream out, final QueryOptions options, LabelPrinter labelPrinter) {
	return new BuildOutputFormatterCallback(out, options.getLineTerminator(), labelPrinter);
	}

	@Override
	public ThreadSafeOutputFormatterCallback<Target> createStreamCallback(
	OutputStream out, QueryOptions options, QueryEnvironment<?> env) {
	return new SynchronizedDelegatingOutputFormatterCallback<>(
	createPostFactoStreamCallback(out, options, env.getLabelPrinter()));
	}

	/** BuildOutputFormatter callback for Query. Made visible for ModQuery. */
	public static class BuildOutputFormatterCallback extends TextOutputFormatterCallback<Target> {
	private final TargetOutputter targetOutputter;

	BuildOutputFormatterCallback(OutputStream out, String lineTerm, LabelPrinter labelPrinter) {
	super(out);
	this.targetOutputter =
	new TargetOutputter(
	writer,
	(rule, attr) -> RawAttributeMapper.of(rule).isConfigurable(attr.getName()),
	lineTerm,
	labelPrinter);
	}

	@Override
	public void processOutput(Iterable<Target> partialResult) throws IOException {
	for (Target target : partialResult) {
	targetOutputter.output(
	target,
	// Multiple possible values are ignored by the outputter.
	(rule, attr) ->
	PossibleAttributeValues.forRuleAndAttribute(
	rule, attr, /mayTreatMultipleAsNone=/ true));
	}
	}
	}

	@Override
	public String getName() {
	return "build";
	}
	}