| // 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.syntax; |
| |
| import com.google.common.annotations.VisibleForTesting; |
| import com.google.common.base.Joiner; |
| import com.google.common.base.Preconditions; |
| import com.google.common.cache.CacheBuilder; |
| import com.google.common.cache.CacheLoader; |
| import com.google.common.cache.LoadingCache; |
| import com.google.common.collect.ImmutableList; |
| import com.google.common.collect.ImmutableMap; |
| import com.google.common.collect.ImmutableSortedMap; |
| import com.google.common.collect.Iterables; |
| import com.google.common.collect.Lists; |
| import com.google.devtools.build.lib.events.Location; |
| import com.google.devtools.build.lib.skylarkinterface.Param; |
| import com.google.devtools.build.lib.skylarkinterface.ParamType; |
| import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable; |
| import com.google.devtools.build.lib.skylarkinterface.SkylarkInterfaceUtils; |
| import com.google.devtools.build.lib.skylarkinterface.SkylarkModule; |
| import com.google.devtools.build.lib.syntax.EvalException.EvalExceptionWithJavaCause; |
| import com.google.devtools.build.lib.syntax.Runtime.NoneType; |
| import com.google.devtools.build.lib.util.Pair; |
| import com.google.devtools.build.lib.util.StringUtilities; |
| import java.io.IOException; |
| import java.lang.reflect.InvocationTargetException; |
| import java.lang.reflect.Method; |
| import java.lang.reflect.Modifier; |
| import java.util.Collections; |
| import java.util.Comparator; |
| import java.util.HashMap; |
| import java.util.LinkedHashMap; |
| import java.util.LinkedHashSet; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Set; |
| import java.util.concurrent.ExecutionException; |
| import javax.annotation.Nullable; |
| |
| /** |
| * Syntax node for a function call expression. |
| */ |
| public final class FuncallExpression extends Expression { |
| |
| /** |
| * A value class to store Methods with their corresponding SkylarkCallable annotations. |
| * This is needed because the annotation is sometimes in a superclass. |
| */ |
| public static final class MethodDescriptor { |
| private final Method method; |
| private final SkylarkCallable annotation; |
| |
| private MethodDescriptor(Method method, SkylarkCallable annotation) { |
| this.method = method; |
| this.annotation = annotation; |
| } |
| |
| Method getMethod() { |
| return method; |
| } |
| |
| /** |
| * Returns the SkylarkCallable annotation corresponding to this method. |
| */ |
| public SkylarkCallable getAnnotation() { |
| return annotation; |
| } |
| } |
| |
| private static final LoadingCache<Class<?>, Map<String, List<MethodDescriptor>>> methodCache = |
| CacheBuilder.newBuilder() |
| .initialCapacity(10) |
| .maximumSize(100) |
| .build( |
| new CacheLoader<Class<?>, Map<String, List<MethodDescriptor>>>() { |
| |
| @Override |
| public Map<String, List<MethodDescriptor>> load(Class<?> key) throws Exception { |
| Map<String, List<MethodDescriptor>> methodMap = new HashMap<>(); |
| for (Method method : key.getMethods()) { |
| // Synthetic methods lead to false multiple matches |
| if (method.isSynthetic()) { |
| continue; |
| } |
| SkylarkCallable callable = SkylarkInterfaceUtils.getSkylarkCallable(method); |
| if (callable == null) { |
| continue; |
| } |
| Preconditions.checkArgument( |
| callable.parameters().length == 0 || !callable.structField(), |
| "Method " |
| + method |
| + " was annotated with both structField and parameters."); |
| if (callable.parameters().length > 0 || callable.mandatoryPositionals() >= 0) { |
| int nbArgs = |
| callable.parameters().length |
| + Math.max(0, callable.mandatoryPositionals()); |
| Preconditions.checkArgument( |
| nbArgs == method.getParameterTypes().length, |
| "Method " |
| + method |
| + " was annotated for " |
| + nbArgs |
| + " arguments " |
| + "but accept only " |
| + method.getParameterTypes().length |
| + " arguments."); |
| } |
| String name = callable.name(); |
| if (name.isEmpty()) { |
| name = StringUtilities.toPythonStyleFunctionName(method.getName()); |
| } |
| if (methodMap.containsKey(name)) { |
| methodMap.get(name).add(new MethodDescriptor(method, callable)); |
| } else { |
| methodMap.put( |
| name, Lists.newArrayList(new MethodDescriptor(method, callable))); |
| } |
| } |
| return ImmutableMap.copyOf(methodMap); |
| } |
| }); |
| |
| /** |
| * Returns a map of methods and corresponding SkylarkCallable annotations of the methods of the |
| * classObj class reachable from Skylark. |
| */ |
| public static ImmutableMap<Method, SkylarkCallable> collectSkylarkMethodsWithAnnotation( |
| Class<?> classObj) { |
| ImmutableSortedMap.Builder<Method, SkylarkCallable> methodMap |
| = ImmutableSortedMap.orderedBy(Comparator.comparing(Object::toString)); |
| for (Method method : classObj.getMethods()) { |
| // Synthetic methods lead to false multiple matches |
| if (!method.isSynthetic()) { |
| SkylarkCallable annotation = SkylarkInterfaceUtils.getSkylarkCallable(classObj, method); |
| if (annotation != null) { |
| methodMap.put(method, annotation); |
| } |
| } |
| } |
| return methodMap.build(); |
| } |
| |
| private static class ArgumentListConversionResult { |
| private final ImmutableList<Object> arguments; |
| private final String error; |
| |
| private ArgumentListConversionResult(ImmutableList<Object> arguments, String error) { |
| this.arguments = arguments; |
| this.error = error; |
| } |
| |
| public static ArgumentListConversionResult fromArgumentList(ImmutableList<Object> arguments) { |
| return new ArgumentListConversionResult(arguments, null); |
| } |
| |
| public static ArgumentListConversionResult fromError(String error) { |
| return new ArgumentListConversionResult(null, error); |
| } |
| |
| public String getError() { |
| return error; |
| } |
| |
| public ImmutableList<Object> getArguments() { |
| return arguments; |
| } |
| } |
| |
| /** |
| * An exception class to handle exceptions in direct Java API calls. |
| */ |
| public static final class FuncallException extends Exception { |
| |
| public FuncallException(String msg) { |
| super(msg); |
| } |
| } |
| |
| private final Expression function; |
| |
| private final ImmutableList<Argument.Passed> arguments; |
| |
| private final int numPositionalArgs; |
| |
| public FuncallExpression(Expression function, ImmutableList<Argument.Passed> arguments) { |
| this.function = Preconditions.checkNotNull(function); |
| this.arguments = Preconditions.checkNotNull(arguments); |
| this.numPositionalArgs = countPositionalArguments(); |
| } |
| |
| /** Returns the function that is called. */ |
| public Expression getFunction() { |
| return this.function; |
| } |
| |
| /** |
| * Returns the number of positional arguments. |
| */ |
| private int countPositionalArguments() { |
| int num = 0; |
| for (Argument.Passed arg : arguments) { |
| if (arg.isPositional()) { |
| num++; |
| } |
| } |
| return num; |
| } |
| |
| /** |
| * Returns an (immutable, ordered) list of function arguments. The first n are |
| * positional and the remaining ones are keyword args, where n = |
| * getNumPositionalArguments(). |
| */ |
| public List<Argument.Passed> getArguments() { |
| return Collections.unmodifiableList(arguments); |
| } |
| |
| /** |
| * Returns the number of arguments which are positional; the remainder are |
| * keyword arguments. |
| */ |
| public int getNumPositionalArguments() { |
| return numPositionalArgs; |
| } |
| |
| @Override |
| public void prettyPrint(Appendable buffer) throws IOException { |
| function.prettyPrint(buffer); |
| buffer.append('('); |
| String sep = ""; |
| for (Argument.Passed arg : arguments) { |
| buffer.append(sep); |
| arg.prettyPrint(buffer); |
| sep = ", "; |
| } |
| buffer.append(')'); |
| } |
| |
| @Override |
| public String toString() { |
| Printer.LengthLimitedPrinter printer = new Printer.LengthLimitedPrinter(); |
| printer.append(function.toString()); |
| printer.printAbbreviatedList(arguments, "(", ", ", ")", null, |
| Printer.SUGGESTED_CRITICAL_LIST_ELEMENTS_COUNT, |
| Printer.SUGGESTED_CRITICAL_LIST_ELEMENTS_STRING_LENGTH); |
| return printer.toString(); |
| } |
| |
| /** |
| * Returns the list of Skylark callable Methods of objClass with the given name and argument |
| * number. |
| */ |
| public static List<MethodDescriptor> getMethods(Class<?> objClass, String methodName) { |
| try { |
| return methodCache.get(objClass).get(methodName); |
| } catch (ExecutionException e) { |
| throw new IllegalStateException("method invocation failed: " + e); |
| } |
| } |
| |
| /** |
| * Returns a set of the Skylark name of all Skylark callable methods for object of type {@code |
| * objClass}. |
| */ |
| public static Set<String> getMethodNames(Class<?> objClass) { |
| try { |
| return methodCache.get(objClass).keySet(); |
| } catch (ExecutionException e) { |
| throw new IllegalStateException("method invocation failed: " + e); |
| } |
| } |
| |
| static Object callMethod(MethodDescriptor methodDescriptor, String methodName, Object obj, |
| Object[] args, Location loc, Environment env) throws EvalException { |
| try { |
| Method method = methodDescriptor.getMethod(); |
| if (obj == null && !Modifier.isStatic(method.getModifiers())) { |
| throw new EvalException(loc, "method '" + methodName + "' is not static"); |
| } |
| // This happens when the interface is public but the implementation classes |
| // have reduced visibility. |
| method.setAccessible(true); |
| Object result = method.invoke(obj, args); |
| if (method.getReturnType().equals(Void.TYPE)) { |
| return Runtime.NONE; |
| } |
| if (result == null) { |
| if (methodDescriptor.getAnnotation().allowReturnNones()) { |
| return Runtime.NONE; |
| } else { |
| throw new EvalException( |
| loc, |
| "method invocation returned None, please file a bug report: " |
| + methodName |
| + Printer.printAbbreviatedList( |
| ImmutableList.copyOf(args), "(", ", ", ")", null)); |
| } |
| } |
| // TODO(bazel-team): get rid of this, by having everyone use the Skylark data structures |
| result = SkylarkType.convertToSkylark(result, method, env); |
| if (result != null && !EvalUtils.isSkylarkAcceptable(result.getClass())) { |
| throw new EvalException( |
| loc, |
| Printer.format( |
| "method '%s' returns an object of invalid type %r", methodName, result.getClass())); |
| } |
| return result; |
| } catch (IllegalAccessException e) { |
| // TODO(bazel-team): Print a nice error message. Maybe the method exists |
| // and an argument is missing or has the wrong type. |
| throw new EvalException(loc, "Method invocation failed: " + e); |
| } catch (InvocationTargetException e) { |
| if (e.getCause() instanceof FuncallException) { |
| throw new EvalException(loc, e.getCause().getMessage()); |
| } else if (e.getCause() != null) { |
| throw new EvalExceptionWithJavaCause(loc, e.getCause()); |
| } else { |
| // This is unlikely to happen |
| throw new EvalException(loc, "method invocation failed: " + e); |
| } |
| } |
| } |
| |
| // TODO(bazel-team): If there's exactly one usable method, this works. If there are multiple |
| // matching methods, it still can be a problem. Figure out how the Java compiler does it |
| // exactly and copy that behaviour. |
| // Throws an EvalException when it cannot find a matching function. |
| private Pair<MethodDescriptor, List<Object>> findJavaMethod( |
| Class<?> objClass, String methodName, List<Object> args, Map<String, Object> kwargs) |
| throws EvalException { |
| Pair<MethodDescriptor, List<Object>> matchingMethod = null; |
| List<MethodDescriptor> methods = getMethods(objClass, methodName); |
| ArgumentListConversionResult argumentListConversionResult = null; |
| if (methods != null) { |
| for (MethodDescriptor method : methods) { |
| if (method.getAnnotation().structField()) { |
| return new Pair<>(method, null); |
| } else { |
| argumentListConversionResult = convertArgumentList(args, kwargs, method); |
| if (argumentListConversionResult.getArguments() != null) { |
| if (matchingMethod == null) { |
| matchingMethod = new Pair<>(method, argumentListConversionResult.getArguments()); |
| } else { |
| throw new EvalException( |
| getLocation(), |
| String.format( |
| "type '%s' has multiple matches for function %s", |
| EvalUtils.getDataTypeNameFromClass(objClass), |
| formatMethod(methodName, args, kwargs))); |
| } |
| } |
| } |
| } |
| } |
| if (matchingMethod == null) { |
| String errorMessage; |
| if (ClassObject.class.isAssignableFrom(objClass)) { |
| errorMessage = String.format("struct has no method '%s'", methodName); |
| } else if (argumentListConversionResult == null |
| || argumentListConversionResult.getError() == null) { |
| errorMessage = |
| String.format( |
| "type '%s' has no method %s", |
| EvalUtils.getDataTypeNameFromClass(objClass), |
| formatMethod(methodName, args, kwargs)); |
| |
| } else { |
| errorMessage = |
| String.format( |
| "%s, in method %s of '%s'", |
| argumentListConversionResult.getError(), |
| formatMethod(methodName, args, kwargs), |
| EvalUtils.getDataTypeNameFromClass(objClass)); |
| } |
| throw new EvalException(getLocation(), errorMessage); |
| } |
| return matchingMethod; |
| } |
| |
| private static SkylarkType getType(Param param) { |
| if (param.allowedTypes().length > 0) { |
| Preconditions.checkState(Object.class.equals(param.type())); |
| SkylarkType result = SkylarkType.BOTTOM; |
| for (ParamType paramType : param.allowedTypes()) { |
| SkylarkType t = |
| paramType.generic1() != Object.class |
| ? SkylarkType.of(paramType.type(), paramType.generic1()) |
| : SkylarkType.of(paramType.type()); |
| result = SkylarkType.Union.of(result, t); |
| } |
| return result; |
| } else { |
| SkylarkType type = |
| param.generic1() != Object.class |
| ? SkylarkType.of(param.type(), param.generic1()) |
| : SkylarkType.of(param.type()); |
| return type; |
| } |
| } |
| |
| /** |
| * Constructs the parameters list to actually pass to the method, filling with default values if |
| * any. If there is a type or argument mismatch, returns a result containing an error message. |
| */ |
| private ArgumentListConversionResult convertArgumentList( |
| List<Object> args, Map<String, Object> kwargs, MethodDescriptor method) { |
| ImmutableList.Builder<Object> builder = ImmutableList.builder(); |
| Class<?>[] params = method.getMethod().getParameterTypes(); |
| SkylarkCallable callable = method.getAnnotation(); |
| int mandatoryPositionals = callable.mandatoryPositionals(); |
| if (mandatoryPositionals < 0) { |
| if (callable.parameters().length > 0) { |
| mandatoryPositionals = 0; |
| } else { |
| mandatoryPositionals = params.length; |
| } |
| } |
| if (mandatoryPositionals > args.size() |
| || args.size() > mandatoryPositionals + callable.parameters().length) { |
| return ArgumentListConversionResult.fromError("too many arguments"); |
| } |
| // First process the legacy positional parameters. |
| int i = 0; |
| if (mandatoryPositionals > 0) { |
| for (Class<?> param : params) { |
| Object value = args.get(i); |
| if (!param.isAssignableFrom(value.getClass())) { |
| return ArgumentListConversionResult.fromError( |
| String.format( |
| "Cannot convert parameter at position %d from type %s to type %s", |
| i, EvalUtils.getDataTypeName(value), param.toString())); |
| } |
| builder.add(value); |
| i++; |
| if (mandatoryPositionals >= 0 && i >= mandatoryPositionals) { |
| // Stops for specified parameters instead. |
| break; |
| } |
| } |
| } |
| |
| // Then the parameters specified in callable.parameters() |
| Set<String> keys = new LinkedHashSet<>(kwargs.keySet()); |
| for (Param param : callable.parameters()) { |
| SkylarkType type = getType(param); |
| if (param.noneable()) { |
| type = SkylarkType.Union.of(type, SkylarkType.NONE); |
| } |
| Object value = null; |
| if (i < args.size()) { |
| value = args.get(i); |
| if (!param.positional()) { |
| return ArgumentListConversionResult.fromError( |
| String.format("Parameter '%s' is not positional", param.name())); |
| } else if (!type.contains(value)) { |
| return ArgumentListConversionResult.fromError( |
| String.format( |
| "Cannot convert parameter '%s' to type %s", param.name(), type.toString())); |
| } |
| i++; |
| } else if (param.named() && keys.remove(param.name())) { |
| // Named parameters |
| value = kwargs.get(param.name()); |
| if (!type.contains(value)) { |
| return ArgumentListConversionResult.fromError( |
| String.format( |
| "Cannot convert parameter '%s' to type %s", param.name(), type.toString())); |
| } |
| } else { |
| // Use default value |
| if (param.defaultValue().isEmpty()) { |
| return ArgumentListConversionResult.fromError( |
| String.format("parameter '%s' has no default value", param.name())); |
| } |
| value = SkylarkSignatureProcessor.getDefaultValue(param, null); |
| } |
| builder.add(value); |
| if (!param.noneable() && value instanceof NoneType) { |
| return ArgumentListConversionResult.fromError( |
| String.format("parameter '%s' cannot be None", param.name())); |
| } |
| } |
| if (i < args.size()) { |
| return ArgumentListConversionResult.fromError("too many arguments"); |
| } |
| if (!keys.isEmpty()) { |
| return ArgumentListConversionResult.fromError( |
| String.format("unexpected keyword%s %s", |
| keys.size() > 1 ? "s" : "", |
| Joiner.on(",").join(Iterables.transform(keys, s -> "'" + s + "'")))); |
| } |
| return ArgumentListConversionResult.fromArgumentList(builder.build()); |
| } |
| |
| private static String formatMethod(String name, List<Object> args, Map<String, Object> kwargs) { |
| StringBuilder sb = new StringBuilder(); |
| sb.append(name).append("("); |
| boolean first = true; |
| for (Object obj : args) { |
| if (!first) { |
| sb.append(", "); |
| } |
| sb.append(EvalUtils.getDataTypeName(obj)); |
| first = false; |
| } |
| for (Map.Entry<String, Object> kwarg : kwargs.entrySet()) { |
| if (!first) { |
| sb.append(", "); |
| } |
| sb.append(EvalUtils.getDataTypeName(kwarg.getValue())); |
| sb.append(" "); |
| sb.append(kwarg.getKey()); |
| first = false; |
| } |
| return sb.append(")").toString(); |
| } |
| |
| /** |
| * Add one argument to the keyword map, registering a duplicate in case of conflict. |
| */ |
| private static void addKeywordArg( |
| Map<String, Object> kwargs, |
| String name, |
| Object value, |
| ImmutableList.Builder<String> duplicates) { |
| if (kwargs.put(name, value) != null) { |
| duplicates.add(name); |
| } |
| } |
| |
| /** |
| * Add multiple arguments to the keyword map (**kwargs), registering duplicates |
| */ |
| private static void addKeywordArgs( |
| Map<String, Object> kwargs, |
| Object items, |
| ImmutableList.Builder<String> duplicates, |
| Location location) |
| throws EvalException { |
| if (!(items instanceof Map<?, ?>)) { |
| throw new EvalException( |
| location, |
| "argument after ** must be a dictionary, not '" + EvalUtils.getDataTypeName(items) + "'"); |
| } |
| for (Map.Entry<?, ?> entry : ((Map<?, ?>) items).entrySet()) { |
| if (!(entry.getKey() instanceof String)) { |
| throw new EvalException( |
| location, |
| "keywords must be strings, not '" + EvalUtils.getDataTypeName(entry.getKey()) + "'"); |
| } |
| addKeywordArg(kwargs, (String) entry.getKey(), entry.getValue(), duplicates); |
| } |
| } |
| |
| /** |
| * Checks whether the given object is a {@link BaseFunction}. |
| * |
| * @throws EvalException If not a BaseFunction. |
| */ |
| private static BaseFunction checkCallable(Object functionValue, Location location) |
| throws EvalException { |
| if (functionValue instanceof BaseFunction) { |
| return (BaseFunction) functionValue; |
| } else { |
| throw new EvalException( |
| location, "'" + EvalUtils.getDataTypeName(functionValue) + "' object is not callable"); |
| } |
| } |
| |
| /** |
| * Check the list from the builder and report an {@link EvalException} if not empty. |
| */ |
| private static void checkDuplicates( |
| ImmutableList.Builder<String> duplicates, Expression function, Location location) |
| throws EvalException { |
| List<String> dups = duplicates.build(); |
| if (!dups.isEmpty()) { |
| throw new EvalException( |
| location, |
| "duplicate keyword" |
| + (dups.size() > 1 ? "s" : "") |
| + " '" |
| + Joiner.on("', '").join(dups) |
| + "' in call to " |
| + function); |
| } |
| } |
| |
| /** |
| * Call a method depending on the type of an object it is called on. |
| * |
| * @param positionals The first object is expected to be the object the method is called on. |
| * @param call the original expression that caused this call, needed for rules especially |
| */ |
| private Object invokeObjectMethod( |
| String method, |
| ImmutableList<Object> positionals, |
| ImmutableMap<String, Object> keyWordArgs, |
| FuncallExpression call, |
| Environment env) |
| throws EvalException, InterruptedException { |
| Location location = call.getLocation(); |
| Object value = positionals.get(0); |
| ImmutableList<Object> positionalArgs = positionals.subList(1, positionals.size()); |
| BaseFunction function = Runtime.getFunction(EvalUtils.getSkylarkType(value.getClass()), method); |
| Object fieldValue = |
| (value instanceof ClassObject) ? ((ClassObject) value).getValue(method) : null; |
| if (function != null) { |
| if (!isNamespace(value.getClass())) { |
| // Use self as an implicit parameter in front. |
| positionalArgs = positionals; |
| } |
| return function.call( |
| positionalArgs, ImmutableMap.copyOf(keyWordArgs), call, env); |
| } else if (fieldValue != null) { |
| if (!(fieldValue instanceof BaseFunction)) { |
| throw new EvalException( |
| location, String.format("struct field '%s' is not a function", method)); |
| } |
| function = (BaseFunction) fieldValue; |
| return function.call( |
| positionalArgs, ImmutableMap.copyOf(keyWordArgs), call, env); |
| } else { |
| // When calling a Java method, the name is not in the Environment, |
| // so evaluating 'function' would fail. |
| Class<?> objClass; |
| Object obj; |
| if (value instanceof Class<?>) { |
| // Static call |
| obj = null; |
| objClass = (Class<?>) value; |
| } else { |
| obj = value; |
| objClass = value.getClass(); |
| } |
| Pair<MethodDescriptor, List<Object>> javaMethod = |
| call.findJavaMethod(objClass, method, positionalArgs, keyWordArgs); |
| if (javaMethod.first.getAnnotation().structField()) { |
| // Not a method but a callable attribute |
| try { |
| return callFunction(javaMethod.first.getMethod().invoke(obj), env); |
| } catch (IllegalAccessException e) { |
| throw new EvalException(getLocation(), "method invocation failed: " + e); |
| } catch (InvocationTargetException e) { |
| if (e.getCause() instanceof FuncallException) { |
| throw new EvalException(getLocation(), e.getCause().getMessage()); |
| } else if (e.getCause() != null) { |
| throw new EvalExceptionWithJavaCause(getLocation(), e.getCause()); |
| } else { |
| // This is unlikely to happen |
| throw new EvalException(getLocation(), "method invocation failed: " + e); |
| } |
| } |
| } |
| return callMethod(javaMethod.first, method, obj, javaMethod.second.toArray(), location, env); |
| } |
| } |
| |
| @SuppressWarnings("unchecked") |
| private void evalArguments(ImmutableList.Builder<Object> posargs, Map<String, Object> kwargs, |
| Environment env) |
| throws EvalException, InterruptedException { |
| ImmutableList.Builder<String> duplicates = new ImmutableList.Builder<>(); |
| // Iterate over the arguments. We assume all positional arguments come before any keyword |
| // or star arguments, because the argument list was already validated by |
| // Argument#validateFuncallArguments, as called by the Parser, |
| // which should be the only place that build FuncallExpression-s. |
| // Argument lists are typically short and functions are frequently called, so go by index |
| // (O(1) for ImmutableList) to avoid the iterator overhead. |
| for (int i = 0; i < arguments.size(); i++) { |
| Argument.Passed arg = arguments.get(i); |
| Object value = arg.getValue().eval(env); |
| if (arg.isPositional()) { |
| posargs.add(value); |
| } else if (arg.isStar()) { // expand the starArg |
| if (!(value instanceof Iterable)) { |
| throw new EvalException( |
| getLocation(), |
| "argument after * must be an iterable, not " + EvalUtils.getDataTypeName(value)); |
| } |
| posargs.addAll((Iterable<Object>) value); |
| } else if (arg.isStarStar()) { // expand the kwargs |
| addKeywordArgs(kwargs, value, duplicates, getLocation()); |
| } else { |
| addKeywordArg(kwargs, arg.getName(), value, duplicates); |
| } |
| } |
| checkDuplicates(duplicates, function, getLocation()); |
| } |
| |
| @VisibleForTesting |
| public static boolean isNamespace(Class<?> classObject) { |
| return classObject.isAnnotationPresent(SkylarkModule.class) |
| && classObject.getAnnotation(SkylarkModule.class).namespace(); |
| } |
| |
| @Override |
| Object doEval(Environment env) throws EvalException, InterruptedException { |
| // TODO: Remove this special case once method resolution and invocation are supported as |
| // separate steps. |
| if (function instanceof DotExpression) { |
| return invokeObjectMethod(env, (DotExpression) function); |
| } |
| Object funcValue = function.eval(env); |
| return callFunction(funcValue, env); |
| } |
| |
| /** Invokes object.function() and returns the result. */ |
| private Object invokeObjectMethod(Environment env, DotExpression dot) |
| throws EvalException, InterruptedException { |
| Object objValue = dot.getObject().eval(env); |
| ImmutableList.Builder<Object> posargs = new ImmutableList.Builder<>(); |
| posargs.add(objValue); |
| // We copy this into an ImmutableMap in the end, but we can't use an ImmutableMap.Builder, or |
| // we'd still have to have a HashMap on the side for the sake of properly handling duplicates. |
| Map<String, Object> kwargs = new LinkedHashMap<>(); |
| evalArguments(posargs, kwargs, env); |
| return invokeObjectMethod( |
| dot.getField().getName(), posargs.build(), ImmutableMap.copyOf(kwargs), this, env); |
| } |
| |
| /** |
| * Calls a function object |
| */ |
| private Object callFunction(Object funcValue, Environment env) |
| throws EvalException, InterruptedException { |
| ImmutableList.Builder<Object> posargs = new ImmutableList.Builder<>(); |
| // We copy this into an ImmutableMap in the end, but we can't use an ImmutableMap.Builder, or |
| // we'd still have to have a HashMap on the side for the sake of properly handling duplicates. |
| Map<String, Object> kwargs = new LinkedHashMap<>(); |
| BaseFunction function = checkCallable(funcValue, getLocation()); |
| evalArguments(posargs, kwargs, env); |
| return function.call(posargs.build(), ImmutableMap.copyOf(kwargs), this, env); |
| } |
| |
| /** |
| * Returns the value of the argument 'name' (or null if there is none). |
| * This function is used to associate debugging information to rules created by skylark "macros". |
| */ |
| @Nullable |
| public String getNameArg() { |
| for (Argument.Passed arg : arguments) { |
| if (arg != null) { |
| String name = arg.getName(); |
| if (name != null && name.equals("name")) { |
| Expression expr = arg.getValue(); |
| return (expr instanceof StringLiteral) ? ((StringLiteral) expr).getValue() : null; |
| } |
| } |
| } |
| return null; |
| } |
| |
| @Override |
| public void accept(SyntaxTreeVisitor visitor) { |
| visitor.visit(this); |
| } |
| |
| @Override |
| public Kind kind() { |
| return Kind.FUNCALL; |
| } |
| |
| @Override |
| protected boolean isNewScope() { |
| return true; |
| } |
| } |
