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-rw-r--r--src/main/java/com/google/devtools/build/lib/syntax/EvalUtils.java590
1 files changed, 590 insertions, 0 deletions
diff --git a/src/main/java/com/google/devtools/build/lib/syntax/EvalUtils.java b/src/main/java/com/google/devtools/build/lib/syntax/EvalUtils.java
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index 0000000000..70d89bc888
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+++ b/src/main/java/com/google/devtools/build/lib/syntax/EvalUtils.java
@@ -0,0 +1,590 @@
+// Copyright 2014 Google Inc. 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.collect.ImmutableList;
+import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.ImmutableSet;
+import com.google.common.collect.Iterables;
+import com.google.common.collect.Lists;
+import com.google.devtools.build.lib.collect.nestedset.NestedSet;
+import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable;
+import com.google.devtools.build.lib.events.Location;
+import com.google.devtools.build.lib.syntax.ClassObject.SkylarkClassObject;
+import com.google.devtools.build.lib.vfs.PathFragment;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Formattable;
+import java.util.Formatter;
+import java.util.IllegalFormatException;
+import java.util.List;
+import java.util.Map;
+import java.util.MissingFormatWidthException;
+import java.util.Set;
+
+/**
+ * Utilities used by the evaluator.
+ */
+public abstract class EvalUtils {
+
+ // TODO(bazel-team): Yet an other hack committed in the name of Skylark. One problem is that the
+ // syntax package cannot depend on actions so we have to have this until Actions are immutable.
+ // The other is that BuildConfigurations are technically not immutable but they cannot be modified
+ // from Skylark.
+ private static final ImmutableSet<Class<?>> quasiImmutableClasses;
+ static {
+ try {
+ ImmutableSet.Builder<Class<?>> builder = ImmutableSet.builder();
+ builder.add(Class.forName("com.google.devtools.build.lib.actions.Action"));
+ builder.add(Class.forName("com.google.devtools.build.lib.analysis.config.BuildConfiguration"));
+ builder.add(Class.forName("com.google.devtools.build.lib.actions.Root"));
+ quasiImmutableClasses = builder.build();
+ } catch (ClassNotFoundException e) {
+ throw new RuntimeException(e);
+ }
+ }
+
+ private EvalUtils() {
+ }
+
+ /**
+ * @return true if the specified sequence is a tuple; false if it's a modifiable list.
+ */
+ public static boolean isTuple(List<?> l) {
+ return isTuple(l.getClass());
+ }
+
+ public static boolean isTuple(Class<?> c) {
+ Preconditions.checkState(List.class.isAssignableFrom(c));
+ if (ImmutableList.class.isAssignableFrom(c)) {
+ return true;
+ } else {
+ return false;
+ }
+ }
+
+ /**
+ * @return true if the specified value is immutable (suitable for use as a
+ * dictionary key) according to the rules of the Build language.
+ */
+ public static boolean isImmutable(Object o) {
+ if (o instanceof Map<?, ?> || o instanceof Function
+ || o instanceof FilesetEntry || o instanceof GlobList<?>) {
+ return false;
+ } else if (o instanceof List<?>) {
+ return isTuple((List<?>) o); // tuples are immutable, lists are not.
+ } else {
+ return true; // string/int
+ }
+ }
+
+ /**
+ * Returns true if the type is immutable in the skylark language.
+ */
+ public static boolean isSkylarkImmutable(Class<?> c) {
+ if (c.isAnnotationPresent(Immutable.class)) {
+ return true;
+ } else if (c.equals(String.class) || c.equals(Integer.class) || c.equals(Boolean.class)
+ || SkylarkList.class.isAssignableFrom(c) || ImmutableMap.class.isAssignableFrom(c)
+ || NestedSet.class.isAssignableFrom(c)) {
+ return true;
+ } else {
+ for (Class<?> classObject : quasiImmutableClasses) {
+ if (classObject.isAssignableFrom(c)) {
+ return true;
+ }
+ }
+ }
+ return false;
+ }
+
+ /**
+ * Returns a transitive superclass or interface implemented by c which is annotated
+ * with SkylarkModule. Returns null if no such class or interface exists.
+ */
+ @VisibleForTesting
+ static Class<?> getParentWithSkylarkModule(Class<?> c) {
+ if (c == null) {
+ return null;
+ }
+ if (c.isAnnotationPresent(SkylarkModule.class)) {
+ return c;
+ }
+ Class<?> parent = getParentWithSkylarkModule(c.getSuperclass());
+ if (parent != null) {
+ return parent;
+ }
+ for (Class<?> ifparent : c.getInterfaces()) {
+ ifparent = getParentWithSkylarkModule(ifparent);
+ if (ifparent != null) {
+ return ifparent;
+ }
+ }
+ return null;
+ }
+
+ /**
+ * Returns the Skylark equivalent type of the parameter. Note that the Skylark
+ * language doesn't have inheritance.
+ */
+ public static Class<?> getSkylarkType(Class<?> c) {
+ if (ImmutableList.class.isAssignableFrom(c)) {
+ return ImmutableList.class;
+ } else if (List.class.isAssignableFrom(c)) {
+ return List.class;
+ } else if (SkylarkList.class.isAssignableFrom(c)) {
+ return SkylarkList.class;
+ } else if (Map.class.isAssignableFrom(c)) {
+ return Map.class;
+ } else if (NestedSet.class.isAssignableFrom(c)) {
+ // This could be removed probably
+ return NestedSet.class;
+ } else if (Set.class.isAssignableFrom(c)) {
+ return Set.class;
+ } else {
+ // Check if one of the superclasses or implemented interfaces has the SkylarkModule
+ // annotation. If yes return that class.
+ Class<?> parent = getParentWithSkylarkModule(c);
+ if (parent != null) {
+ return parent;
+ }
+ }
+ return c;
+ }
+
+ /**
+ * Returns a pretty name for the datatype of object 'o' in the Build language.
+ */
+ public static String getDatatypeName(Object o) {
+ Preconditions.checkNotNull(o);
+ if (o instanceof SkylarkList) {
+ return ((SkylarkList) o).isTuple() ? "tuple" : "list";
+ }
+ return getDataTypeNameFromClass(o.getClass());
+ }
+
+ /**
+ * Returns a pretty name for the datatype equivalent of class 'c' in the Build language.
+ */
+ public static String getDataTypeNameFromClass(Class<?> c) {
+ if (c.equals(Object.class)) {
+ return "unknown";
+ } else if (c.equals(String.class)) {
+ return "string";
+ } else if (c.equals(Integer.class)) {
+ return "int";
+ } else if (c.equals(Boolean.class)) {
+ return "bool";
+ } else if (c.equals(Void.TYPE) || c.equals(Environment.NoneType.class)) {
+ return "None";
+ } else if (List.class.isAssignableFrom(c)) {
+ return isTuple(c) ? "tuple" : "list";
+ } else if (GlobList.class.isAssignableFrom(c)) {
+ return "list";
+ } else if (Map.class.isAssignableFrom(c)) {
+ return "dict";
+ } else if (Function.class.isAssignableFrom(c)) {
+ return "function";
+ } else if (c.equals(FilesetEntry.class)) {
+ return "FilesetEntry";
+ } else if (NestedSet.class.isAssignableFrom(c) || SkylarkNestedSet.class.isAssignableFrom(c)) {
+ return "set";
+ } else if (SkylarkClassObject.class.isAssignableFrom(c)) {
+ return "struct";
+ } else if (SkylarkList.class.isAssignableFrom(c)) {
+ // TODO(bazel-team): this is not entirely correct, it can also be a tuple.
+ return "list";
+ } else if (c.isAnnotationPresent(SkylarkModule.class)) {
+ SkylarkModule module = c.getAnnotation(SkylarkModule.class);
+ return c.getAnnotation(SkylarkModule.class).name()
+ + (module.namespace() ? " (a language module)" : "");
+ } else {
+ if (c.getSimpleName().isEmpty()) {
+ return c.getName();
+ } else {
+ return c.getSimpleName();
+ }
+ }
+ }
+
+ /**
+ * Returns a sequence of the appropriate list/tuple datatype for 'seq', based on 'isTuple'.
+ */
+ public static List<?> makeSequence(List<?> seq, boolean isTuple) {
+ return isTuple ? ImmutableList.copyOf(seq) : seq;
+ }
+
+ /**
+ * Print build-language value 'o' in display format into the specified buffer.
+ */
+ public static void printValue(Object o, Appendable buffer) {
+ // Exception-swallowing wrapper due to annoying Appendable interface.
+ try {
+ printValueX(o, buffer);
+ } catch (IOException e) {
+ throw new AssertionError(e); // can't happen
+ }
+ }
+
+ private static void printValueX(Object o, Appendable buffer)
+ throws IOException {
+ if (o == null) {
+ throw new NullPointerException(); // None is not a build language value.
+ } else if (o instanceof String ||
+ o instanceof Integer ||
+ o instanceof Double) {
+ buffer.append(o.toString());
+
+ } else if (o == Environment.NONE) {
+ buffer.append("None");
+
+ } else if (o == Boolean.TRUE) {
+ buffer.append("True");
+
+ } else if (o == Boolean.FALSE) {
+ buffer.append("False");
+
+ } else if (o instanceof List<?>) {
+ List<?> seq = (List<?>) o;
+ boolean isTuple = isImmutable(seq);
+ String sep = "";
+ buffer.append(isTuple ? '(' : '[');
+ for (int ii = 0, len = seq.size(); ii < len; ++ii) {
+ buffer.append(sep);
+ prettyPrintValue(seq.get(ii), buffer);
+ sep = ", ";
+ }
+ buffer.append(isTuple ? ')' : ']');
+
+ } else if (o instanceof Map<?, ?>) {
+ Map<?, ?> dict = (Map<?, ?>) o;
+ buffer.append('{');
+ String sep = "";
+ for (Map.Entry<?, ?> entry : dict.entrySet()) {
+ buffer.append(sep);
+ prettyPrintValue(entry.getKey(), buffer);
+ buffer.append(": ");
+ prettyPrintValue(entry.getValue(), buffer);
+ sep = ", ";
+ }
+ buffer.append('}');
+
+ } else if (o instanceof Function) {
+ Function func = (Function) o;
+ buffer.append("<function " + func.getName() + ">");
+
+ } else if (o instanceof FilesetEntry) {
+ FilesetEntry entry = (FilesetEntry) o;
+ buffer.append("FilesetEntry(srcdir = ");
+ prettyPrintValue(entry.getSrcLabel().toString(), buffer);
+ buffer.append(", files = ");
+ prettyPrintValue(makeStringList(entry.getFiles()), buffer);
+ buffer.append(", excludes = ");
+ prettyPrintValue(makeList(entry.getExcludes()), buffer);
+ buffer.append(", destdir = ");
+ prettyPrintValue(entry.getDestDir().getPathString(), buffer);
+ buffer.append(", strip_prefix = ");
+ prettyPrintValue(entry.getStripPrefix(), buffer);
+ buffer.append(", symlinks = \"");
+ buffer.append(entry.getSymlinkBehavior().toString());
+ buffer.append("\")");
+ } else if (o instanceof PathFragment) {
+ buffer.append(((PathFragment) o).getPathString());
+ } else {
+ buffer.append(o.toString());
+ }
+ }
+
+ private static List<?> makeList(Collection<?> list) {
+ return list == null ? Lists.newArrayList() : Lists.newArrayList(list);
+ }
+
+ private static List<String> makeStringList(List<Label> labels) {
+ if (labels == null) { return Collections.emptyList(); }
+ List<String> strings = Lists.newArrayListWithCapacity(labels.size());
+ for (Label label : labels) {
+ strings.add(label.toString());
+ }
+ return strings;
+ }
+
+ /**
+ * Print build-language value 'o' in parseable format into the specified
+ * buffer. (Only differs from printValueX in treatment of strings at toplevel,
+ * i.e. not within a sequence or dict)
+ */
+ public static void prettyPrintValue(Object o, Appendable buffer) {
+ // Exception-swallowing wrapper due to annoying Appendable interface.
+ try {
+ prettyPrintValueX(o, buffer);
+ } catch (IOException e) {
+ throw new AssertionError(e); // can't happen
+ }
+ }
+
+ private static void prettyPrintValueX(Object o, Appendable buffer)
+ throws IOException {
+ if (o instanceof Label) {
+ o = o.toString(); // Pretty-print a label like a string
+ }
+ if (o instanceof String) {
+ String s = (String) o;
+ buffer.append('"');
+ for (int ii = 0, len = s.length(); ii < len; ++ii) {
+ char c = s.charAt(ii);
+ switch (c) {
+ case '\r':
+ buffer.append('\\').append('r');
+ break;
+ case '\n':
+ buffer.append('\\').append('n');
+ break;
+ case '\t':
+ buffer.append('\\').append('t');
+ break;
+ case '\"':
+ buffer.append('\\').append('"');
+ break;
+ default:
+ if (c < 32) {
+ buffer.append(String.format("\\x%02x", (int) c));
+ } else {
+ buffer.append(c); // no need to support UTF-8
+ }
+ } // endswitch
+ }
+ buffer.append('\"');
+ } else {
+ printValueX(o, buffer);
+ }
+ }
+
+ /**
+ * Pretty-print value 'o' to a string. Convenience overloading of
+ * prettyPrintValue(Object, Appendable).
+ */
+ public static String prettyPrintValue(Object o) {
+ StringBuffer buffer = new StringBuffer();
+ prettyPrintValue(o, buffer);
+ return buffer.toString();
+ }
+
+ /**
+ * Pretty-print values of 'o' separated by the separator.
+ */
+ public static String prettyPrintValues(String separator, Iterable<Object> o) {
+ return Joiner.on(separator).join(Iterables.transform(o,
+ new com.google.common.base.Function<Object, String>() {
+ @Override
+ public String apply(Object input) {
+ return prettyPrintValue(input);
+ }
+ }));
+ }
+
+ /**
+ * Print value 'o' to a string. Convenience overloading of printValue(Object, Appendable).
+ */
+ public static String printValue(Object o) {
+ StringBuffer buffer = new StringBuffer();
+ printValue(o, buffer);
+ return buffer.toString();
+ }
+
+ public static Object checkNotNull(Expression expr, Object obj) throws EvalException {
+ if (obj == null) {
+ throw new EvalException(expr.getLocation(),
+ "Unexpected null value, please send a bug report. "
+ + "This was generated by '" + expr + "'");
+ }
+ return obj;
+ }
+
+ /**
+ * Convert BUILD language objects to Formattable so JDK can render them correctly.
+ * Don't do this for numeric or string types because we want %d, %x, %s to work.
+ */
+ private static Object makeFormattable(final Object o) {
+ if (o instanceof Integer || o instanceof Double || o instanceof String) {
+ return o;
+ } else {
+ return new Formattable() {
+ @Override
+ public String toString() {
+ return "Formattable[" + o + "]";
+ }
+
+ @Override
+ public void formatTo(Formatter formatter, int flags, int width,
+ int precision) {
+ printValue(o, formatter.out());
+ }
+ };
+ }
+ }
+
+ private static final Object[] EMPTY = new Object[0];
+
+ /*
+ * N.B. MissingFormatWidthException is the only kind of IllegalFormatException
+ * whose constructor can take and display arbitrary error message, hence its use below.
+ */
+
+ /**
+ * Perform Python-style string formatting. Implemented by delegation to Java's
+ * own string formatting routine to avoid reinventing the wheel. In more
+ * obscure cases, semantics follow JDK (not Python) rules.
+ *
+ * @param pattern a format string.
+ * @param tuple a tuple containing positional arguments
+ */
+ public static String formatString(String pattern, List<?> tuple)
+ throws IllegalFormatException {
+ int count = countPlaceholders(pattern);
+ if (count < tuple.size()) {
+ throw new MissingFormatWidthException(
+ "not all arguments converted during string formatting");
+ }
+
+ List<Object> args = new ArrayList<>();
+
+ for (Object o : tuple) {
+ args.add(makeFormattable(o));
+ }
+
+ try {
+ return String.format(pattern, args.toArray(EMPTY));
+ } catch (IllegalFormatException e) {
+ throw new MissingFormatWidthException(
+ "invalid arguments for format string");
+ }
+ }
+
+ private static int countPlaceholders(String pattern) {
+ int length = pattern.length();
+ boolean afterPercent = false;
+ int i = 0;
+ int count = 0;
+ while (i < length) {
+ switch (pattern.charAt(i)) {
+ case 's':
+ case 'd':
+ if (afterPercent) {
+ count++;
+ afterPercent = false;
+ }
+ break;
+
+ case '%':
+ afterPercent = !afterPercent;
+ break;
+
+ default:
+ if (afterPercent) {
+ throw new MissingFormatWidthException("invalid arguments for format string");
+ }
+ afterPercent = false;
+ break;
+ }
+ i++;
+ }
+
+ return count;
+ }
+
+ /**
+ * @return the truth value of an object, according to Python rules.
+ * http://docs.python.org/2/library/stdtypes.html#truth-value-testing
+ */
+ public static boolean toBoolean(Object o) {
+ if (o == null || o == Environment.NONE) {
+ return false;
+ } else if (o instanceof Boolean) {
+ return (Boolean) o;
+ } else if (o instanceof String) {
+ return !((String) o).isEmpty();
+ } else if (o instanceof Integer) {
+ return (Integer) o != 0;
+ } else if (o instanceof Collection<?>) {
+ return !((Collection<?>) o).isEmpty();
+ } else if (o instanceof Map<?, ?>) {
+ return !((Map<?, ?>) o).isEmpty();
+ } else if (o instanceof NestedSet<?>) {
+ return !((NestedSet<?>) o).isEmpty();
+ } else if (o instanceof SkylarkNestedSet) {
+ return !((SkylarkNestedSet) o).isEmpty();
+ } else if (o instanceof Iterable<?>) {
+ return !(Iterables.isEmpty((Iterable<?>) o));
+ } else {
+ return true;
+ }
+ }
+
+ @SuppressWarnings("unchecked")
+ public static Collection<Object> toCollection(Object o, Location loc) throws EvalException {
+ if (o instanceof Collection) {
+ return (Collection<Object>) o;
+ } else if (o instanceof Map<?, ?>) {
+ // For dictionaries we iterate through the keys only
+ return ((Map<Object, Object>) o).keySet();
+ } else if (o instanceof SkylarkNestedSet) {
+ return ((SkylarkNestedSet) o).toCollection();
+ } else {
+ throw new EvalException(loc,
+ "type '" + EvalUtils.getDatatypeName(o) + "' is not a collection");
+ }
+ }
+
+ @SuppressWarnings("unchecked")
+ public static Iterable<Object> toIterable(Object o, Location loc) throws EvalException {
+ if (o instanceof String) {
+ // This is not as efficient as special casing String in for and dict and list comprehension
+ // statements. However this is a more unified way.
+ // The regex matches every character in the string until the end of the string,
+ // so "abc" will be split into ["a", "b", "c"].
+ return ImmutableList.<Object>copyOf(((String) o).split("(?!^)"));
+ } else if (o instanceof Iterable) {
+ return (Iterable<Object>) o;
+ } else if (o instanceof Map<?, ?>) {
+ // For dictionaries we iterate through the keys only
+ return ((Map<Object, Object>) o).keySet();
+ } else {
+ throw new EvalException(loc,
+ "type '" + EvalUtils.getDatatypeName(o) + "' is not an iterable");
+ }
+ }
+
+ /**
+ * Returns the size of the Skylark object or -1 in case the object doesn't have a size.
+ */
+ public static int size(Object arg) {
+ if (arg instanceof String) {
+ return ((String) arg).length();
+ } else if (arg instanceof Map) {
+ return ((Map<?, ?>) arg).size();
+ } else if (arg instanceof SkylarkList) {
+ return ((SkylarkList) arg).size();
+ } else if (arg instanceof Iterable) {
+ // Iterables.size() checks if arg is a Collection so it's efficient in that sense.
+ return Iterables.size((Iterable<?>) arg);
+ }
+ return -1;
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-09 08:07:31 +0000