| // 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.annotations.VisibleForTesting; |
| import com.google.common.base.Joiner; |
| import com.google.common.base.Objects; |
| import com.google.common.base.Preconditions; |
| import com.google.common.collect.ImmutableCollection; |
| import com.google.common.collect.ImmutableSortedMap; |
| import com.google.common.collect.Ordering; |
| import com.google.devtools.build.lib.events.Location; |
| import com.google.devtools.build.lib.skylarkbuildapi.StructApi; |
| import com.google.devtools.build.lib.skylarkinterface.SkylarkPrinter; |
| import com.google.devtools.build.lib.syntax.ClassObject; |
| import com.google.devtools.build.lib.syntax.Environment; |
| 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.Runtime; |
| import com.google.devtools.build.lib.syntax.SkylarkDict; |
| import com.google.devtools.build.lib.syntax.SkylarkList; |
| import com.google.devtools.build.lib.syntax.SkylarkType; |
| import com.google.protobuf.TextFormat; |
| import java.io.Serializable; |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.List; |
| import java.util.Map; |
| import javax.annotation.Nullable; |
| |
| /** |
| * A generic skylark object with fields, constructable by calling {@code struct()} in skylark. |
| */ |
| public abstract class StructImpl extends Info |
| implements ClassObject, StructApi, Serializable { |
| |
| /** |
| * 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) { |
| super(provider, location); |
| } |
| |
| /** |
| * Preprocesses a map of field values to convert the field names and field values to |
| * Skylark-acceptable names and types. |
| * |
| * <p>Entries are ordered by key. |
| */ |
| static ImmutableSortedMap<String, Object> copyValues(Map<String, Object> values) { |
| Preconditions.checkNotNull(values); |
| ImmutableSortedMap.Builder<String, Object> builder = ImmutableSortedMap.naturalOrder(); |
| for (Map.Entry<String, Object> e : values.entrySet()) { |
| builder.put( |
| Attribute.getSkylarkName(e.getKey()), |
| SkylarkType.convertToSkylark(e.getValue(), (Environment) null)); |
| } |
| return builder.build(); |
| } |
| |
| /** |
| * Returns whether the given field name exists. |
| * |
| * <p>This conceptually extends the API for {@link ClassObject}. |
| */ |
| public abstract boolean hasField(String name); |
| |
| /** |
| * <p>Wraps {@link ClassObject#getValue(String)}, returning null in cases where |
| * {@link EvalException} would have been thrown. |
| */ |
| @VisibleForTesting |
| public Object getValueOrNull(String name) { |
| try { |
| return getValue(name); |
| } catch (EvalException e) { |
| return null; |
| } |
| } |
| |
| /** |
| * Returns the result of {@link #getValue(String)}, cast as the given type, throwing {@link |
| * EvalException} if the cast fails. |
| */ |
| public <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); |
| } |
| |
| /** |
| * {@inheritDoc} |
| * |
| * <p>Overrides {@link ClassObject#getFieldNames()}, but does not allow {@link EvalException} to |
| * be thrown. |
| */ |
| @Override |
| public abstract ImmutableCollection<String> getFieldNames(); |
| |
| /** |
| * 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 provider.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.provider.equals(other.provider)) { |
| 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(provider); |
| 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(SkylarkPrinter 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(")"); |
| } |
| |
| @Override |
| public String toProto(Location loc) throws EvalException { |
| StringBuilder sb = new StringBuilder(); |
| printProtoTextMessage(this, sb, 0, loc); |
| return sb.toString(); |
| } |
| |
| private void printProtoTextMessage(ClassObject object, StringBuilder sb, int indent, Location loc) |
| 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, loc); |
| } |
| } |
| |
| private void printProtoTextMessage( |
| String key, Object value, StringBuilder sb, int indent, Location loc, 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, loc); |
| printProtoTextMessage("value", entry.getValue(), sb, indent + 1, loc); |
| print(sb, "}", indent); |
| } else if (value instanceof ClassObject) { |
| print(sb, key + " {", indent); |
| printProtoTextMessage((ClassObject) value, sb, indent + 1, loc); |
| 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 new EvalException( |
| loc, |
| "Invalid text format, expected a struct, a dict, a string, a bool, or an int but got a " |
| + EvalUtils.getDataTypeName(value) |
| + " for " |
| + container |
| + " '" |
| + key |
| + "'"); |
| } |
| } |
| |
| private void printProtoTextMessage( |
| String key, Object value, StringBuilder sb, int indent, Location loc) throws EvalException { |
| if (value instanceof SkylarkList) { |
| for (Object item : ((SkylarkList) 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, loc, "list element in struct field"); |
| } |
| } else if (value instanceof SkylarkDict) { |
| for (Map.Entry<?, ?> entry : ((SkylarkDict<?, ?>) value).entrySet()) { |
| printProtoTextMessage(key, entry, sb, indent, loc, "entry of dictionary"); |
| } |
| } else { |
| printProtoTextMessage(key, value, sb, indent, loc, "struct field"); |
| } |
| } |
| |
| private 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(Location loc) throws EvalException { |
| StringBuilder sb = new StringBuilder(); |
| printJson(this, sb, loc, "struct field", null); |
| return sb.toString(); |
| } |
| |
| private void printJson(Object value, StringBuilder sb, Location loc, String container, String key) |
| throws EvalException { |
| if (value == Runtime.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, loc, "struct field", field); |
| } |
| sb.append("}"); |
| } else if (value instanceof SkylarkDict) { |
| sb.append("{"); |
| String join = ""; |
| for (Map.Entry<?, ?> entry : ((SkylarkDict<?, ?>) value).entrySet()) { |
| sb.append(join); |
| join = ","; |
| if (!(entry.getKey() instanceof String)) { |
| String errorMessage = |
| "Keys must be a string but got a " |
| + EvalUtils.getDataTypeName(entry.getKey()) |
| + " for " |
| + container; |
| if (key != null) { |
| errorMessage += " '" + key + "'"; |
| } |
| throw new EvalException(loc, errorMessage); |
| } |
| sb.append("\""); |
| sb.append(entry.getKey()); |
| sb.append("\":"); |
| printJson(entry.getValue(), sb, loc, "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, loc, "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 { |
| String errorMessage = |
| "Invalid text format, expected a struct, a string, a bool, or an int " |
| + "but got a " |
| + EvalUtils.getDataTypeName(value) |
| + " for " |
| + container; |
| if (key != null) { |
| errorMessage += " '" + key + "'"; |
| } |
| throw new EvalException(loc, errorMessage); |
| } |
| } |
| |
| private String jsonEscapeString(String string) { |
| return escapeDoubleQuotesAndBackslashesAndNewlines(string) |
| .replace("\r", "\\r") |
| .replace("\t", "\\t"); |
| } |
| |
| @Override |
| public String toString() { |
| return Printer.repr(this); |
| } |
| } |