src/main/java/com/google/devtools/build/lib/packages/StructImpl.java - bazel - Git at Google

 // Copyright 2016 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.packages;

 import com.google.common.base.Joiner;
 import com.google.common.base.Objects;
 import com.google.common.collect.Ordering;
 import com.google.devtools.build.lib.events.Location;
 import com.google.devtools.build.lib.skylarkbuildapi.core.StructApi;
 import com.google.devtools.build.lib.syntax.ClassObject;
 import com.google.devtools.build.lib.syntax.Dict;
 import com.google.devtools.build.lib.syntax.EvalException;
 import com.google.devtools.build.lib.syntax.EvalUtils;
 import com.google.devtools.build.lib.syntax.Printer;
 import com.google.devtools.build.lib.syntax.Sequence;
 import com.google.devtools.build.lib.syntax.SkylarkType;
 import com.google.devtools.build.lib.syntax.Starlark;
 import com.google.protobuf.TextFormat;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import javax.annotation.Nullable;

 /**
  * An abstract base class for Starlark values that have fields, have to_json and to_proto methods,
  * have an associated provider (type symbol), and may be returned as the result of analysis from one
  * target to another.
  *
  * <p>StructImpl does not specify how the fields are represented; subclasses must define {@code
  * getValue} and {@code getFieldNames}. For example, {@code NativeInfo} supplies fields from the
  * subclass's {@code SkylarkCallable(structField=true)} annotations, and {@code SkylarkInfo}
  * supplies fields from the map provided at its construction.
  *
  * <p>Two StructImpls are equivalent if they have the same provider and, for each field name
  * reported by {@code getFieldNames} their corresponding field values are equivalent, or accessing
  * them both returns an error.
  */
 public abstract class StructImpl implements Info, ClassObject, StructApi {

   private final Provider provider;
   private final Location location;

   /**
    * Constructs an {@link StructImpl}.
    *
    * @param provider the provider describing the type of this instance
    * @param location the Skylark location where this instance is created. If null, defaults to
    *     {@link Location#BUILTIN}.
    */
   protected StructImpl(Provider provider, @Nullable Location location) {
     this.provider = provider;
     this.location = location != null ? location : Location.BUILTIN;
   }

   @Override
   public Provider getProvider() {
     return provider;
   }

   @Override
   public Location getCreationLoc() {
     return location;
   }

   /**
    * Returns the result of {@link #getValue(String)}, cast as the given type, throwing {@link
    * EvalException} if the cast fails.
    */
   public final <T> T getValue(String key, Class<T> type) throws EvalException {
     Object obj = getValue(key);
     if (obj == null) {
       return null;
     }
     SkylarkType.checkType(obj, type, key);
     return type.cast(obj);
   }

   /**
    * Returns the error message format to use for unknown fields.
    *
    * <p>By default, it is the one specified by the provider.
    */
   protected String getErrorMessageFormatForUnknownField() {
     return getProvider().getErrorMessageFormatForUnknownField();
   }

   @Override
   public String getErrorMessageForUnknownField(String name) {
     String suffix = "Available attributes: "
         + Joiner.on(", ").join(Ordering.natural().sortedCopy(getFieldNames()));
     return String.format(getErrorMessageFormatForUnknownField(), name) + "\n" + suffix;
   }

   @Override
   public boolean equals(Object otherObject) {
     if (!(otherObject instanceof StructImpl)) {
       return false;
     }
     StructImpl other = (StructImpl) otherObject;
     if (this == other) {
       return true;
     }
     if (!this.getProvider().equals(other.getProvider())) {
       return false;
     }
     // Compare objects' fields and their values
     if (!this.getFieldNames().equals(other.getFieldNames())) {
       return false;
     }
     for (String field : getFieldNames()) {
       if (!Objects.equal(this.getValueOrNull(field), other.getValueOrNull(field))) {
         return false;
       }
     }
     return true;
   }

   @Override
   public int hashCode() {
     List<String> fields = new ArrayList<>(getFieldNames());
     Collections.sort(fields);
     List<Object> objectsToHash = new ArrayList<>();
     objectsToHash.add(getProvider());
     for (String field : fields) {
       objectsToHash.add(field);
       objectsToHash.add(getValueOrNull(field));
     }
     return Objects.hashCode(objectsToHash.toArray());
   }

   /**
    * Convert the object to string using Skylark syntax. The output tries to be reversible (but there
    * is no guarantee, it depends on the actual values).
    */
   @Override
   public void repr(Printer printer) {
     boolean first = true;
     printer.append("struct(");
     // Sort by key to ensure deterministic output.
     for (String fieldName : Ordering.natural().sortedCopy(getFieldNames())) {
       if (!first) {
         printer.append(", ");
       }
       first = false;
       printer.append(fieldName);
       printer.append(" = ");
       printer.repr(getValueOrNull(fieldName));
     }
     printer.append(")");
   }

   private Object getValueOrNull(String name) {
     try {
       return getValue(name);
     } catch (EvalException e) {
       return null;
     }
   }

   @Override
   public String toProto() throws EvalException {
     StringBuilder sb = new StringBuilder();
     printProtoTextMessage(this, sb, 0);
     return sb.toString();
   }

   private static void printProtoTextMessage(ClassObject object, StringBuilder sb, int indent)
       throws EvalException {
     // For determinism sort the fields alphabetically.
     List<String> fields = new ArrayList<>(object.getFieldNames());
     Collections.sort(fields);
     for (String field : fields) {
       printProtoTextMessage(field, object.getValue(field), sb, indent);
     }
   }

   private static void printProtoTextMessage(
       String key, Object value, StringBuilder sb, int indent, String container)
       throws EvalException {
     if (value instanceof Map.Entry) {
       Map.Entry<?, ?> entry = (Map.Entry<?, ?>) value;
       print(sb, key + " {", indent);
       printProtoTextMessage("key", entry.getKey(), sb, indent + 1);
       printProtoTextMessage("value", entry.getValue(), sb, indent + 1);
       print(sb, "}", indent);
     } else if (value instanceof ClassObject) {
       print(sb, key + " {", indent);
       printProtoTextMessage((ClassObject) value, sb, indent + 1);
       print(sb, "}", indent);
     } else if (value instanceof String) {
       print(
           sb,
           key + ": \"" + escapeDoubleQuotesAndBackslashesAndNewlines((String) value) + "\"",
           indent);
     } else if (value instanceof Integer) {
       print(sb, key + ": " + value, indent);
     } else if (value instanceof Boolean) {
       // We're relying on the fact that Java converts Booleans to Strings in the same way
       // as the protocol buffers do.
       print(sb, key + ": " + value, indent);
     } else {
       throw Starlark.errorf(
           "Invalid text format, expected a struct, a dict, a string, a bool, or an int but got a"
               + " %s for %s '%s'",
           EvalUtils.getDataTypeName(value), container, key);
     }
   }

   private static void printProtoTextMessage(String key, Object value, StringBuilder sb, int indent)
       throws EvalException {
     if (value instanceof Sequence) {
       for (Object item : ((Sequence) value)) {
         // TODO(bazel-team): There should be some constraint on the fields of the structs
         // in the same list but we ignore that for now.
         printProtoTextMessage(key, item, sb, indent, "list element in struct field");
       }
     } else if (value instanceof Dict) {
       for (Map.Entry<?, ?> entry : ((Dict<?, ?>) value).entrySet()) {
         printProtoTextMessage(key, entry, sb, indent, "entry of dictionary");
       }
     } else {
       printProtoTextMessage(key, value, sb, indent, "struct field");
     }
   }

   private static void print(StringBuilder sb, String text, int indent) {
     for (int i = 0; i < indent; i++) {
       sb.append("  ");
     }
     sb.append(text);
     sb.append("\n");
   }

   /**
    * Escapes the given string for use in proto/JSON string.
    *
    * <p>This escapes double quotes, backslashes, and newlines.
    */
   private static String escapeDoubleQuotesAndBackslashesAndNewlines(String string) {
     return TextFormat.escapeDoubleQuotesAndBackslashes(string).replace("\n", "\\n");
   }

   @Override
   public String toJson() throws EvalException {
     StringBuilder sb = new StringBuilder();
     printJson(this, sb, "struct field", null);
     return sb.toString();
   }

   private static void printJson(Object value, StringBuilder sb, String container, String key)
       throws EvalException {
     if (value == Starlark.NONE) {
       sb.append("null");
     } else if (value instanceof ClassObject) {
       sb.append("{");

       String join = "";
       for (String field : ((ClassObject) value).getFieldNames()) {
         sb.append(join);
         join = ",";
         sb.append("\"");
         sb.append(field);
         sb.append("\":");
         printJson(((ClassObject) value).getValue(field), sb, "struct field", field);
       }
       sb.append("}");
     } else if (value instanceof Dict) {
       sb.append("{");
       String join = "";
       for (Map.Entry<?, ?> entry : ((Dict<?, ?>) value).entrySet()) {
         sb.append(join);
         join = ",";
         if (!(entry.getKey() instanceof String)) {
           throw Starlark.errorf(
               "Keys must be a string but got a %s for %s%s",
               EvalUtils.getDataTypeName(entry.getKey()),
               container,
               key != null ? " '" + key + "'" : "");
         }
         sb.append("\"");
         sb.append(entry.getKey());
         sb.append("\":");
         printJson(entry.getValue(), sb, "dict value", String.valueOf(entry.getKey()));
       }
       sb.append("}");
     } else if (value instanceof List) {
       sb.append("[");
       String join = "";
       for (Object item : ((List) value)) {
         sb.append(join);
         join = ",";
         printJson(item, sb, "list element in struct field", key);
       }
       sb.append("]");
     } else if (value instanceof String) {
       sb.append("\"");
       sb.append(jsonEscapeString((String) value));
       sb.append("\"");
     } else if (value instanceof Integer || value instanceof Boolean) {
       sb.append(value);
     } else {
       throw Starlark.errorf(
           "Invalid text format, expected a struct, a string, a bool, or an int but got a %s for"
               + " %s%s",
           EvalUtils.getDataTypeName(value), container, key != null ? " '" + key + "'" : "");
     }
   }

   private static String jsonEscapeString(String string) {
     return escapeDoubleQuotesAndBackslashesAndNewlines(string)
         .replace("\r", "\\r")
         .replace("\t", "\\t");
   }

   @Override
   public String toString() {
     return Starlark.repr(this);
   }
 }
	// Copyright 2016 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.packages;

	import com.google.common.base.Joiner;
	import com.google.common.base.Objects;
	import com.google.common.collect.Ordering;
	import com.google.devtools.build.lib.events.Location;
	import com.google.devtools.build.lib.skylarkbuildapi.core.StructApi;
	import com.google.devtools.build.lib.syntax.ClassObject;
	import com.google.devtools.build.lib.syntax.Dict;
	import com.google.devtools.build.lib.syntax.EvalException;
	import com.google.devtools.build.lib.syntax.EvalUtils;
	import com.google.devtools.build.lib.syntax.Printer;
	import com.google.devtools.build.lib.syntax.Sequence;
	import com.google.devtools.build.lib.syntax.SkylarkType;
	import com.google.devtools.build.lib.syntax.Starlark;
	import com.google.protobuf.TextFormat;
	import java.util.ArrayList;
	import java.util.Collections;
	import java.util.List;
	import java.util.Map;
	import javax.annotation.Nullable;

	/**
	* An abstract base class for Starlark values that have fields, have to_json and to_proto methods,
	* have an associated provider (type symbol), and may be returned as the result of analysis from one
	* target to another.
	*
	* <p>StructImpl does not specify how the fields are represented; subclasses must define {@code
	* getValue} and {@code getFieldNames}. For example, {@code NativeInfo} supplies fields from the
	* subclass's {@code SkylarkCallable(structField=true)} annotations, and {@code SkylarkInfo}
	* supplies fields from the map provided at its construction.
	*
	* <p>Two StructImpls are equivalent if they have the same provider and, for each field name
	* reported by {@code getFieldNames} their corresponding field values are equivalent, or accessing
	* them both returns an error.
	*/
	public abstract class StructImpl implements Info, ClassObject, StructApi {

	private final Provider provider;
	private final Location location;

	/**
	* Constructs an {@link StructImpl}.
	*
	* @param provider the provider describing the type of this instance
	* @param location the Skylark location where this instance is created. If null, defaults to
	* {@link Location#BUILTIN}.
	*/
	protected StructImpl(Provider provider, @Nullable Location location) {
	this.provider = provider;
	this.location = location != null ? location : Location.BUILTIN;
	}

	@Override
	public Provider getProvider() {
	return provider;
	}

	@Override
	public Location getCreationLoc() {
	return location;
	}

	/**
	* Returns the result of {@link #getValue(String)}, cast as the given type, throwing {@link
	* EvalException} if the cast fails.
	*/
	public final <T> T getValue(String key, Class<T> type) throws EvalException {
	Object obj = getValue(key);
	if (obj == null) {
	return null;
	}
	SkylarkType.checkType(obj, type, key);
	return type.cast(obj);
	}

	/**
	* Returns the error message format to use for unknown fields.
	*
	* <p>By default, it is the one specified by the provider.
	*/
	protected String getErrorMessageFormatForUnknownField() {
	return getProvider().getErrorMessageFormatForUnknownField();
	}

	@Override
	public String getErrorMessageForUnknownField(String name) {
	String suffix = "Available attributes: "
	+ Joiner.on(", ").join(Ordering.natural().sortedCopy(getFieldNames()));
	return String.format(getErrorMessageFormatForUnknownField(), name) + "\n" + suffix;
	}

	@Override
	public boolean equals(Object otherObject) {
	if (!(otherObject instanceof StructImpl)) {
	return false;
	}
	StructImpl other = (StructImpl) otherObject;
	if (this == other) {
	return true;
	}
	if (!this.getProvider().equals(other.getProvider())) {
	return false;
	}
	// Compare objects' fields and their values
	if (!this.getFieldNames().equals(other.getFieldNames())) {
	return false;
	}
	for (String field : getFieldNames()) {
	if (!Objects.equal(this.getValueOrNull(field), other.getValueOrNull(field))) {
	return false;
	}
	}
	return true;
	}

	@Override
	public int hashCode() {
	List<String> fields = new ArrayList<>(getFieldNames());
	Collections.sort(fields);
	List<Object> objectsToHash = new ArrayList<>();
	objectsToHash.add(getProvider());
	for (String field : fields) {
	objectsToHash.add(field);
	objectsToHash.add(getValueOrNull(field));
	}
	return Objects.hashCode(objectsToHash.toArray());
	}

	/**
	* Convert the object to string using Skylark syntax. The output tries to be reversible (but there
	* is no guarantee, it depends on the actual values).
	*/
	@Override
	public void repr(Printer printer) {
	boolean first = true;
	printer.append("struct(");
	// Sort by key to ensure deterministic output.
	for (String fieldName : Ordering.natural().sortedCopy(getFieldNames())) {
	if (!first) {
	printer.append(", ");
	}
	first = false;
	printer.append(fieldName);
	printer.append(" = ");
	printer.repr(getValueOrNull(fieldName));
	}
	printer.append(")");
	}

	private Object getValueOrNull(String name) {
	try {
	return getValue(name);
	} catch (EvalException e) {
	return null;
	}
	}

	@Override
	public String toProto() throws EvalException {
	StringBuilder sb = new StringBuilder();
	printProtoTextMessage(this, sb, 0);
	return sb.toString();
	}

	private static void printProtoTextMessage(ClassObject object, StringBuilder sb, int indent)
	throws EvalException {
	// For determinism sort the fields alphabetically.
	List<String> fields = new ArrayList<>(object.getFieldNames());
	Collections.sort(fields);
	for (String field : fields) {
	printProtoTextMessage(field, object.getValue(field), sb, indent);
	}
	}

	private static void printProtoTextMessage(
	String key, Object value, StringBuilder sb, int indent, String container)
	throws EvalException {
	if (value instanceof Map.Entry) {
	Map.Entry<?, ?> entry = (Map.Entry<?, ?>) value;
	print(sb, key + " {", indent);
	printProtoTextMessage("key", entry.getKey(), sb, indent + 1);
	printProtoTextMessage("value", entry.getValue(), sb, indent + 1);
	print(sb, "}", indent);
	} else if (value instanceof ClassObject) {
	print(sb, key + " {", indent);
	printProtoTextMessage((ClassObject) value, sb, indent + 1);
	print(sb, "}", indent);
	} else if (value instanceof String) {
	print(
	sb,
	key + ": \"" + escapeDoubleQuotesAndBackslashesAndNewlines((String) value) + "\"",
	indent);
	} else if (value instanceof Integer) {
	print(sb, key + ": " + value, indent);
	} else if (value instanceof Boolean) {
	// We're relying on the fact that Java converts Booleans to Strings in the same way
	// as the protocol buffers do.
	print(sb, key + ": " + value, indent);
	} else {
	throw Starlark.errorf(
	"Invalid text format, expected a struct, a dict, a string, a bool, or an int but got a"
	+ " %s for %s '%s'",
	EvalUtils.getDataTypeName(value), container, key);
	}
	}

	private static void printProtoTextMessage(String key, Object value, StringBuilder sb, int indent)
	throws EvalException {
	if (value instanceof Sequence) {
	for (Object item : ((Sequence) value)) {
	// TODO(bazel-team): There should be some constraint on the fields of the structs
	// in the same list but we ignore that for now.
	printProtoTextMessage(key, item, sb, indent, "list element in struct field");
	}
	} else if (value instanceof Dict) {
	for (Map.Entry<?, ?> entry : ((Dict<?, ?>) value).entrySet()) {
	printProtoTextMessage(key, entry, sb, indent, "entry of dictionary");
	}
	} else {
	printProtoTextMessage(key, value, sb, indent, "struct field");
	}
	}

	private static void print(StringBuilder sb, String text, int indent) {
	for (int i = 0; i < indent; i++) {
	sb.append(" ");
	}
	sb.append(text);
	sb.append("\n");
	}

	/**
	* Escapes the given string for use in proto/JSON string.
	*
	* <p>This escapes double quotes, backslashes, and newlines.
	*/
	private static String escapeDoubleQuotesAndBackslashesAndNewlines(String string) {
	return TextFormat.escapeDoubleQuotesAndBackslashes(string).replace("\n", "\\n");
	}

	@Override
	public String toJson() throws EvalException {
	StringBuilder sb = new StringBuilder();
	printJson(this, sb, "struct field", null);
	return sb.toString();
	}

	private static void printJson(Object value, StringBuilder sb, String container, String key)
	throws EvalException {
	if (value == Starlark.NONE) {
	sb.append("null");
	} else if (value instanceof ClassObject) {
	sb.append("{");

	String join = "";
	for (String field : ((ClassObject) value).getFieldNames()) {
	sb.append(join);
	join = ",";
	sb.append("\"");
	sb.append(field);
	sb.append("\":");
	printJson(((ClassObject) value).getValue(field), sb, "struct field", field);
	}
	sb.append("}");
	} else if (value instanceof Dict) {
	sb.append("{");
	String join = "";
	for (Map.Entry<?, ?> entry : ((Dict<?, ?>) value).entrySet()) {
	sb.append(join);
	join = ",";
	if (!(entry.getKey() instanceof String)) {
	throw Starlark.errorf(
	"Keys must be a string but got a %s for %s%s",
	EvalUtils.getDataTypeName(entry.getKey()),
	container,
	key != null ? " '" + key + "'" : "");
	}
	sb.append("\"");
	sb.append(entry.getKey());
	sb.append("\":");
	printJson(entry.getValue(), sb, "dict value", String.valueOf(entry.getKey()));
	}
	sb.append("}");
	} else if (value instanceof List) {
	sb.append("[");
	String join = "";
	for (Object item : ((List) value)) {
	sb.append(join);
	join = ",";
	printJson(item, sb, "list element in struct field", key);
	}
	sb.append("]");
	} else if (value instanceof String) {
	sb.append("\"");
	sb.append(jsonEscapeString((String) value));
	sb.append("\"");
	} else if (value instanceof Integer \|\| value instanceof Boolean) {
	sb.append(value);
	} else {
	throw Starlark.errorf(
	"Invalid text format, expected a struct, a string, a bool, or an int but got a %s for"
	+ " %s%s",
	EvalUtils.getDataTypeName(value), container, key != null ? " '" + key + "'" : "");
	}
	}

	private static String jsonEscapeString(String string) {
	return escapeDoubleQuotesAndBackslashesAndNewlines(string)
	.replace("\r", "\\r")
	.replace("\t", "\\t");
	}

	@Override
	public String toString() {
	return Starlark.repr(this);
	}
	}