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/*
* Copyright 2008 The Closure Compiler Authors.
*
* 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.javascript.jscomp;
import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.base.Preconditions.checkState;
import static java.lang.Math.max;
import static java.lang.Math.min;
import com.google.common.annotations.GwtIncompatible;
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.Iterables;
import com.google.common.collect.LinkedListMultimap;
import com.google.common.collect.ListMultimap;
import com.google.common.collect.Ordering;
import com.google.gson.JsonArray;
import com.google.gson.JsonObject;
import com.google.gson.JsonPrimitive;
import com.google.javascript.jscomp.base.format.SimpleFormat;
import com.google.javascript.jscomp.deps.SortedDependencies;
import com.google.javascript.jscomp.deps.SortedDependencies.MissingProvideException;
import com.google.javascript.jscomp.graph.LinkedDirectedGraph;
import com.google.javascript.rhino.StaticSourceFile.SourceKind;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.BitSet;
import java.util.Collection;
import java.util.IdentityHashMap;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.jspecify.nullness.Nullable;
/**
* A {@link JSChunk} dependency graph that assigns a depth to each chunk and can answer
* depth-related queries about them. For the purposes of this class, a chunk's depth is defined as
* the number of hops in the longest (non cyclic) path from the chunk to a chunk with no
* dependencies.
*/
public final class JSChunkGraph implements Serializable {
static final DiagnosticType WEAK_FILE_REACHABLE_FROM_ENTRY_POINT_ERROR =
DiagnosticType.error(
"JSC_WEAK_FILE_REACHABLE_FROM_ENTRY_POINT_ERROR",
"File strongly reachable from an entry point must not be weak: {0}");
static final DiagnosticType EXPLICIT_WEAK_ENTRY_POINT_ERROR =
DiagnosticType.error(
"JSC_EXPLICIT_WEAK_ENTRY_POINT_ERROR",
"Explicit entry point input must not be weak: {0}");
static final DiagnosticType IMPLICIT_WEAK_ENTRY_POINT_ERROR =
DiagnosticType.warning(
"JSC_IMPLICIT_WEAK_ENTRY_POINT_ERROR",
"Implicit entry point input should not be weak: {0}");
private final JSChunk[] chunks;
/**
* selfPlusTransitiveDeps[i] = indices of all chunks that chunks[i] depends on, including itself.
*/
private final BitSet[] selfPlusTransitiveDeps;
/** subtreeSize[i] = Number of chunks that transitively depend on chunks[i], including itself. */
private final int[] subtreeSize;
/**
* Lists of chunks at each depth. chunksByDepth.get(3) is a list of the chunks at
* depth 3, for example.
*/
private final List> chunksByDepth;
/**
* dependencyMap is a cache of dependencies that makes the dependsOn function faster. Each map
* entry associates a starting JSChunk with the set of JSChunks that are transitively dependent on
* the starting chunk.
*
* If the cache returns null, then the entry hasn't been filled in for that chunk.
*
*
NOTE: JSChunk has identity semantics so this map implementation is safe
*/
private final IdentityHashMap> dependencyMap = new IdentityHashMap<>();
/** Creates a chunk graph from a list of chunks in dependency order. */
public JSChunkGraph(JSChunk[] chunksInDepOrder) {
this(Arrays.asList(chunksInDepOrder));
}
/** Creates a chunk graph from a list of chunks in dependency order. */
public JSChunkGraph(List chunksInDepOrder) {
Preconditions.checkState(!chunksInDepOrder.isEmpty());
chunksInDepOrder = makeWeakChunk(chunksInDepOrder);
chunks = new JSChunk[chunksInDepOrder.size()];
// n = number of chunks
// Populate chunks O(n)
for (int chunkIndex = 0; chunkIndex < chunks.length; ++chunkIndex) {
final JSChunk chunk = chunksInDepOrder.get(chunkIndex);
checkState(chunk.getIndex() == -1, "Chunk index already set: %s", chunk);
chunk.setIndex(chunkIndex);
chunks[chunkIndex] = chunk;
}
// Determine depth for all chunks.
// m = number of edges in the graph
// O(n*m)
chunksByDepth = initChunksByDepth();
// Determine transitive deps for all chunks.
// O(n*m * log(n)) (probably a bit better than that)
selfPlusTransitiveDeps = initTransitiveDepsBitSets();
// O(n*m)
subtreeSize = initSubtreeSize();
// Move all sources marked as weak by outside sources (e.g. flags) into the weak chunk.
moveMarkedWeakSources(getChunkByName(JSChunk.WEAK_CHUNK_NAME), getAllInputs());
}
private List> initChunksByDepth() {
final List> tmpChunksByDepth = new ArrayList<>();
for (int chunkIndex = 0; chunkIndex < chunks.length; ++chunkIndex) {
final JSChunk chunk = chunks[chunkIndex];
checkState(chunk.getDepth() == -1, "Chunk depth already set: %s", chunk);
int depth = 0;
for (JSChunk dep : chunk.getDependencies()) {
int depDepth = dep.getDepth();
if (depDepth < 0) {
throw new ChunkDependenceException(
SimpleFormat.format(
"Chunks not in dependency order: %s preceded %s", chunk.getName(), dep.getName()),
chunk,
dep);
}
depth = max(depth, depDepth + 1);
}
chunk.setDepth(depth);
if (depth == tmpChunksByDepth.size()) {
tmpChunksByDepth.add(new ArrayList());
}
tmpChunksByDepth.get(depth).add(chunk);
}
return tmpChunksByDepth;
}
/**
* If a weak chunk doesn't already exist, creates a weak chunk depending on every other chunk.
*
* Does not move any sources into the weak chunk.
*
* @return a new list of chunks that includes the weak chunk, if it was newly created, or the same
* list if the weak chunk already existed
* @throws IllegalStateException if a weak chunk already exists but doesn't fulfill the above
* conditions
*/
private List makeWeakChunk(List chunksInDepOrder) {
boolean hasWeakChunk = false;
for (JSChunk chunk : chunksInDepOrder) {
if (chunk.getName().equals(JSChunk.WEAK_CHUNK_NAME)) {
hasWeakChunk = true;
Set allOtherChunks = new LinkedHashSet<>(chunksInDepOrder);
allOtherChunks.remove(chunk);
checkState(
chunk.getAllDependencies().containsAll(allOtherChunks),
"A weak chunk already exists but it does not depend on every other chunk.");
checkState(
chunk.getAllDependencies().size() == allOtherChunks.size(),
"The weak chunk cannot have extra dependencies.");
break;
}
}
if (hasWeakChunk) {
// All weak files (and only weak files) should be in the weak chunk.
List misplacedWeakFiles = new ArrayList<>();
List misplacedStrongFiles = new ArrayList<>();
for (JSChunk chunk : chunksInDepOrder) {
boolean isWeakChunk = chunk.getName().equals(JSChunk.WEAK_CHUNK_NAME);
for (CompilerInput input : chunk.getInputs()) {
if (isWeakChunk && !input.getSourceFile().isWeak()) {
misplacedStrongFiles.add(input.getSourceFile().getName());
} else if (!isWeakChunk && input.getSourceFile().isWeak()) {
misplacedWeakFiles.add(
input.getSourceFile().getName() + " (in chunk " + chunk.getName() + ")");
}
}
}
if (!(misplacedStrongFiles.isEmpty() && misplacedWeakFiles.isEmpty())) {
StringBuilder sb = new StringBuilder("A weak chunk exists but some sources are misplaced.");
if (!misplacedStrongFiles.isEmpty()) {
sb.append("\nFound these strong sources in the weak chunk:\n ")
.append(Joiner.on("\n ").join(misplacedStrongFiles));
}
if (!misplacedWeakFiles.isEmpty()) {
sb.append("\nFound these weak sources in other chunks:\n ")
.append(Joiner.on("\n ").join(misplacedWeakFiles));
}
throw new IllegalStateException(sb.toString());
}
} else {
JSChunk weakChunk = new JSChunk(JSChunk.WEAK_CHUNK_NAME);
for (JSChunk chunk : chunksInDepOrder) {
weakChunk.addDependency(chunk);
}
chunksInDepOrder = new ArrayList<>(chunksInDepOrder);
chunksInDepOrder.add(weakChunk);
}
return chunksInDepOrder;
}
private BitSet[] initTransitiveDepsBitSets() {
BitSet[] array = new BitSet[chunks.length];
for (int chunkIndex = 0; chunkIndex < chunks.length; ++chunkIndex) {
final JSChunk chunk = chunks[chunkIndex];
BitSet selfPlusTransitiveDeps = new BitSet(chunkIndex + 1);
array[chunkIndex] = selfPlusTransitiveDeps;
selfPlusTransitiveDeps.set(chunkIndex);
// O(chunkIndex * log64(chunkIndex))
for (JSChunk dep : chunk.getDependencies()) {
// Add this dependency and all of its dependencies to the current chunk.
// O(log64(chunkIndex))
selfPlusTransitiveDeps.or(array[dep.getIndex()]);
}
}
return array;
}
private int[] initSubtreeSize() {
int[] subtreeSize = new int[chunks.length];
for (int dependentIndex = 0; dependentIndex < chunks.length; ++dependentIndex) {
BitSet dependencies = selfPlusTransitiveDeps[dependentIndex];
// Iterating backward through the bitset is slightly more efficient, since it avoids
// considering later chunks, which this one cannot depend on.
for (int requiredIndex = dependentIndex;
requiredIndex >= 0;
requiredIndex = dependencies.previousSetBit(requiredIndex - 1)) {
subtreeSize[requiredIndex] += 1; // Count dependent in required chunk's subtree.
}
}
return subtreeSize;
}
/** Gets an iterable over all input source files in dependency order. */
Iterable getAllInputs() {
return Iterables.concat(Iterables.transform(Arrays.asList(chunks), JSChunk::getInputs));
}
/** Gets the total number of input source files. */
int getInputCount() {
int count = 0;
for (JSChunk chunk : chunks) {
count += chunk.getInputCount();
}
return count;
}
/** Gets an iterable over all chunks in dependency order. */
Iterable getAllChunks() {
return Arrays.asList(chunks);
}
/**
* Gets a single chunk by name.
*
* @return The chunk, or null if no such chunk exists.
*/
@Nullable
JSChunk getChunkByName(String name) {
for (JSChunk m : chunks) {
if (m.getName().equals(name)) {
return m;
}
}
return null;
}
/** Gets all chunks indexed by name. */
Map getChunksByName() {
Map result = new LinkedHashMap<>();
for (JSChunk m : chunks) {
result.put(m.getName(), m);
}
return result;
}
/** Gets the total number of chunks. */
int getChunkCount() {
return chunks.length;
}
/** Gets the root chunk. */
JSChunk getRootChunk() {
return Iterables.getOnlyElement(chunksByDepth.get(0));
}
/**
* Returns a JSON representation of the JSChunkGraph. Specifically a JsonArray of "Chunks" where
* each chunk has a - "name" - "dependencies" (list of chunk names) - "transitive-dependencies"
* (list of chunk names, deepest first) - "inputs" (list of file names)
*
* @return List of chunk JSONObjects.
*/
@GwtIncompatible("com.google.gson")
JsonArray toJson() {
JsonArray chunks = new JsonArray();
for (JSChunk chunk : getAllChunks()) {
JsonObject node = new JsonObject();
node.add("name", new JsonPrimitive(chunk.getName()));
JsonArray deps = new JsonArray();
node.add("dependencies", deps);
for (JSChunk m : chunk.getDependencies()) {
deps.add(new JsonPrimitive(m.getName()));
}
JsonArray transitiveDeps = new JsonArray();
node.add("transitive-dependencies", transitiveDeps);
for (JSChunk m : getTransitiveDepsDeepestFirst(chunk)) {
transitiveDeps.add(new JsonPrimitive(m.getName()));
}
JsonArray inputs = new JsonArray();
node.add("inputs", inputs);
for (CompilerInput input : chunk.getInputs()) {
inputs.add(new JsonPrimitive(input.getSourceFile().getName()));
}
chunks.add(node);
}
return chunks;
}
/**
* Determines whether this chunk depends on a given chunk. Note that a chunk never depends on
* itself, as that dependency would be cyclic.
*/
public boolean dependsOn(JSChunk src, JSChunk m) {
return src != m && selfPlusTransitiveDeps[src.getIndex()].get(m.getIndex());
}
/**
* Finds the chunk with the fewest transitive dependents on which all of the given chunks depend
* and that is a subtree of the given parent chunk tree.
*
* If no such subtree can be found, the parent chunk is returned.
*
*
If multiple candidates have the same number of dependents, the chunk farthest down in the
* total ordering of chunks will be chosen.
*
* @param parentTree chunk on which the result must depend
* @param dependentChunks indices of chunks to consider
* @return A chunk on which all of the argument chunks depend
*/
public JSChunk getSmallestCoveringSubtree(JSChunk parentTree, BitSet dependentChunks) {
checkState(!dependentChunks.isEmpty());
// Candidate chunks are those that all of the given dependent chunks depend on, including
// themselves. The dependent chunk with the smallest index might be our answer, if all
// the other chunks depend on it.
int minDependentChunkIndex = chunks.length;
final BitSet candidates = new BitSet(chunks.length);
candidates.set(0, chunks.length, true);
for (int dependentIndex = dependentChunks.nextSetBit(0);
dependentIndex >= 0;
dependentIndex = dependentChunks.nextSetBit(dependentIndex + 1)) {
minDependentChunkIndex = min(minDependentChunkIndex, dependentIndex);
candidates.and(selfPlusTransitiveDeps[dependentIndex]);
}
checkState(!candidates.isEmpty(), "No common dependency found for %s", dependentChunks);
// All candidates must have an index <= the smallest dependent chunk index.
// Work backwards through the candidates starting with the dependent chunk with the smallest
// index. For each candidate, we'll remove all of the chunks it depends on from consideration,
// since they must all have larger subtrees than the one we're considering.
int parentTreeIndex = parentTree.getIndex();
// default to parent tree if we don't find anything better
int bestCandidateIndex = parentTreeIndex;
for (int candidateIndex = candidates.previousSetBit(minDependentChunkIndex);
candidateIndex >= 0;
candidateIndex = candidates.previousSetBit(candidateIndex - 1)) {
BitSet candidatePlusTransitiveDeps = selfPlusTransitiveDeps[candidateIndex];
if (candidatePlusTransitiveDeps.get(parentTreeIndex)) {
// candidate is a subtree of parentTree
candidates.andNot(candidatePlusTransitiveDeps);
if (subtreeSize[candidateIndex] < subtreeSize[bestCandidateIndex]) {
bestCandidateIndex = candidateIndex;
}
} // eliminate candidates that are not a subtree of parentTree
}
return chunks[bestCandidateIndex];
}
/**
* Finds the deepest common dependency of two chunks, not including the two chunks themselves.
*
* @param m1 A chunk in this graph
* @param m2 A chunk in this graph
* @return The deepest common dep of {@code m1} and {@code m2}, or null if they have no common
* dependencies
*/
@Nullable
JSChunk getDeepestCommonDependency(JSChunk m1, JSChunk m2) {
int m1Depth = m1.getDepth();
int m2Depth = m2.getDepth();
// According our definition of depth, the result must have a strictly
// smaller depth than either m1 or m2.
for (int depth = min(m1Depth, m2Depth) - 1; depth >= 0; depth--) {
List chunksAtDepth = chunksByDepth.get(depth);
// Look at the chunks at this depth in reverse order, so that we use the
// original ordering of the chunks to break ties (later meaning deeper).
for (int i = chunksAtDepth.size() - 1; i >= 0; i--) {
JSChunk m = chunksAtDepth.get(i);
if (dependsOn(m1, m) && dependsOn(m2, m)) {
return m;
}
}
}
return null;
}
/**
* Finds the deepest common dependency of two chunks, including the chunks themselves.
*
* @param m1 A chunk in this graph
* @param m2 A chunk in this graph
* @return The deepest common dep of {@code m1} and {@code m2}, or null if they have no common
* dependencies
*/
public JSChunk getDeepestCommonDependencyInclusive(JSChunk m1, JSChunk m2) {
if (m2 == m1 || dependsOn(m2, m1)) {
return m1;
} else if (dependsOn(m1, m2)) {
return m2;
}
return getDeepestCommonDependency(m1, m2);
}
/** Returns the deepest common dependency of the given chunks. */
public JSChunk getDeepestCommonDependencyInclusive(Collection chunks) {
Iterator iter = chunks.iterator();
JSChunk dep = iter.next();
while (iter.hasNext()) {
dep = getDeepestCommonDependencyInclusive(dep, iter.next());
}
return dep;
}
/**
* Creates an iterable over the transitive dependencies of chunk {@code m} in a non-increasing
* depth ordering. The result does not include the chunk {@code m}.
*
* @param m A chunk in this graph
* @return The transitive dependencies of chunk {@code m}
*/
@VisibleForTesting
List getTransitiveDepsDeepestFirst(JSChunk m) {
return InverseDepthComparator.INSTANCE.sortedCopy(getTransitiveDeps(m));
}
/** Returns the transitive dependencies of the chunk. */
private Set getTransitiveDeps(JSChunk m) {
return dependencyMap.computeIfAbsent(m, JSChunk::getAllDependencies);
}
/**
* Moves all sources that have {@link SourceKind#WEAK} into the weak chunk so that they may be
* pruned later.
*/
private static void moveMarkedWeakSources(JSChunk weakChunk, Iterable inputs) {
checkNotNull(weakChunk);
ImmutableList allInputs = ImmutableList.copyOf(inputs);
for (CompilerInput i : allInputs) {
if (i.getSourceFile().isWeak()) {
JSChunk existingChunk = i.getChunk();
if (existingChunk == weakChunk) {
continue;
}
if (existingChunk != null) {
existingChunk.remove(i);
}
weakChunk.add(i);
}
}
}
/**
* Apply the dependency options to the list of sources, returning a new source list re-ordering
* and dropping files as necessary. This chunk graph will be updated to reflect the new list.
*
* See {@link DependencyOptions} for more information on how this works.
*
* @throws MissingProvideException if an entry point was not provided by any of the inputs.
*/
public ImmutableList manageDependencies(
AbstractCompiler compiler, DependencyOptions dependencyOptions)
throws MissingProvideException, MissingChunkException {
// Make a copy since we're going to mutate the graph below.
ImmutableList originalInputs = ImmutableList.copyOf(getAllInputs());
SortedDependencies sorter = new SortedDependencies<>(originalInputs);
Set entryPointInputs =
createEntryPointInputs(compiler, dependencyOptions, getAllInputs(), sorter);
// Build a map of symbols to their source file(s). While having multiple source files is invalid
// we leave that up to typechecking so that we avoid arbitarily picking a file.
LinkedHashMap> inputsByProvide = new LinkedHashMap<>();
for (CompilerInput input : originalInputs) {
for (String provide : input.getKnownProvides()) {
inputsByProvide.computeIfAbsent(provide, (String k) -> new LinkedHashSet<>());
inputsByProvide.get(provide).add(input);
}
String chunkName = input.getPath().toModuleName();
inputsByProvide.computeIfAbsent(chunkName, (String k) -> new LinkedHashSet<>());
inputsByProvide.get(chunkName).add(input);
}
// Dynamically imported files must be added to the chunk graph, but
// they should not be ordered ahead of the files that import them.
// We add them as entry points to ensure they get included.
for (CompilerInput input : originalInputs) {
for (String require : input.getDynamicRequires()) {
if (inputsByProvide.containsKey(require)) {
entryPointInputs.addAll(inputsByProvide.get(require));
}
}
}
// For goog.requireDynamic() imported files.
for (CompilerInput input : originalInputs) {
for (String require : input.getRequireDynamicImports()) {
if (inputsByProvide.containsKey(require)) {
entryPointInputs.addAll(inputsByProvide.get(require));
}
}
}
// The order of inputs, sorted independently of chunks.
ImmutableList absoluteOrder =
sorter.getStrongDependenciesOf(originalInputs, dependencyOptions.shouldSort());
// Figure out which sources *must* be in each chunk.
ListMultimap entryPointInputsPerChunk = LinkedListMultimap.create();
for (CompilerInput input : entryPointInputs) {
JSChunk chunk = input.getChunk();
checkNotNull(chunk);
entryPointInputsPerChunk.put(chunk, input);
}
// Clear the chunks of their inputs. This also nulls out the input's reference to its chunk.
for (JSChunk chunk : getAllChunks()) {
chunk.removeAll();
}
// Figure out which sources *must* be in each chunk, or in one
// of that chunk's dependencies.
List orderedInputs = new ArrayList<>();
Set reachedInputs = new LinkedHashSet<>();
for (JSChunk chunk : chunks) {
List transitiveClosure;
// Prefer a depth first ordering of dependencies from entry points.
// Always orders in a deterministic fashion regardless of the order of provided inputs
// given the same entry points in the same order.
if (dependencyOptions.shouldSort() && dependencyOptions.shouldPrune()) {
transitiveClosure = new ArrayList<>();
// We need the ful set of dependencies for each chunk, so start with the full input set
Set inputsNotYetReached = new LinkedHashSet<>(originalInputs);
for (CompilerInput entryPoint : entryPointInputsPerChunk.get(chunk)) {
transitiveClosure.addAll(
getDepthFirstDependenciesOf(entryPoint, inputsNotYetReached, inputsByProvide));
}
// For any input we have not yet reached, add them to the ordered list
for (CompilerInput orderedInput : transitiveClosure) {
if (reachedInputs.add(orderedInput)) {
orderedInputs.add(orderedInput);
}
}
} else {
// Simply order inputs so that any required namespace comes before it's usage.
// Ordered result varies based on the original order of inputs.
transitiveClosure =
sorter.getStrongDependenciesOf(
entryPointInputsPerChunk.get(chunk), dependencyOptions.shouldSort());
}
for (CompilerInput input : transitiveClosure) {
if (dependencyOptions.shouldPrune()
&& input.getSourceFile().isWeak()
&& !entryPointInputs.contains(input)) {
compiler.report(
JSError.make(
WEAK_FILE_REACHABLE_FROM_ENTRY_POINT_ERROR, input.getSourceFile().getName()));
}
JSChunk oldChunk = input.getChunk();
if (oldChunk == null) {
input.setModule(chunk);
} else {
input.setModule(null);
input.setModule(getDeepestCommonDependencyInclusive(oldChunk, chunk));
}
}
}
if (!(dependencyOptions.shouldSort() && dependencyOptions.shouldPrune())
|| entryPointInputsPerChunk.isEmpty()) {
orderedInputs = absoluteOrder;
}
JSChunk weakChunk = getChunkByName(JSChunk.WEAK_CHUNK_NAME);
checkNotNull(weakChunk);
// Mark all sources that are detected as weak.
if (dependencyOptions.shouldPrune()) {
ImmutableList weakInputs = sorter.getSortedWeakDependenciesOf(orderedInputs);
for (CompilerInput i : weakInputs) {
// Add weak inputs to the weak chunk in dependency order. moveMarkedWeakSources will move
// in command line flag order.
checkState(i.getChunk() == null);
i.getSourceFile().setKind(SourceKind.WEAK);
i.setModule(weakChunk);
weakChunk.add(i);
}
} else {
// Only move sourced marked as weak if the compiler isn't doing its own detection.
moveMarkedWeakSources(weakChunk, originalInputs);
}
// All the inputs are pointing to the chunks that own them. Yeah!
// Update the chunks to reflect this.
for (CompilerInput input : orderedInputs) {
JSChunk chunk = input.getChunk();
if (chunk != null && chunk.getByName(input.getName()) == null) {
chunk.add(input);
}
}
// Now, generate the sorted result.
ImmutableList.Builder result = ImmutableList.builder();
for (JSChunk chunk : getAllChunks()) {
result.addAll(chunk.getInputs());
}
return result.build();
}
/**
* Given an input and set of unprocessed inputs, return the input and it's strong dependencies by
* performing a recursive, depth-first traversal.
*/
private List getDepthFirstDependenciesOf(
CompilerInput rootInput,
Set unreachedInputs,
Map> inputsByProvide) {
List orderedInputs = new ArrayList<>();
if (!unreachedInputs.remove(rootInput)) {
return orderedInputs;
}
for (String importedNamespace : rootInput.getRequiredSymbols()) {
if (inputsByProvide.containsKey(importedNamespace)) {
for (CompilerInput input : inputsByProvide.get(importedNamespace)) {
if (unreachedInputs.contains(input)) {
orderedInputs.addAll(
getDepthFirstDependenciesOf(input, unreachedInputs, inputsByProvide));
}
}
}
}
orderedInputs.add(rootInput);
return orderedInputs;
}
private Set createEntryPointInputs(
AbstractCompiler compiler,
DependencyOptions dependencyOptions,
Iterable inputs,
SortedDependencies sorter)
throws MissingChunkException, MissingProvideException {
Set entryPointInputs = new LinkedHashSet<>();
Map chunksByName = getChunksByName();
if (dependencyOptions.shouldPrune()) {
// Some files implicitly depend on base.js without actually requiring anything.
// So we always treat it as the first entry point to ensure it's ordered correctly.
CompilerInput baseJs = sorter.maybeGetInputProviding("goog");
if (baseJs != null) {
entryPointInputs.add(baseJs);
}
if (!dependencyOptions.shouldDropMoochers()) {
for (CompilerInput entryPointInput : sorter.getInputsWithoutProvides()) {
if (entryPointInput.getSourceFile().isWeak()) {
compiler.report(
JSError.make(
IMPLICIT_WEAK_ENTRY_POINT_ERROR, entryPointInput.getSourceFile().getName()));
} else {
entryPointInputs.add(entryPointInput);
}
}
}
for (ModuleIdentifier entryPoint : dependencyOptions.getEntryPoints()) {
CompilerInput entryPointInput = null;
try {
if (entryPoint.getClosureNamespace().equals(entryPoint.getModuleName())) {
entryPointInput = sorter.maybeGetInputProviding(entryPoint.getClosureNamespace());
// Check to see if we can find the entry point as an ES6 and CommonJS module
// ES6 and CommonJS entry points may not provide any symbols
if (entryPointInput == null) {
entryPointInput = sorter.getInputProviding(entryPoint.getName());
}
} else {
JSChunk chunk = chunksByName.get(entryPoint.getModuleName());
if (chunk == null) {
throw new MissingChunkException(entryPoint.getModuleName());
} else {
entryPointInput = sorter.getInputProviding(entryPoint.getClosureNamespace());
entryPointInput.overrideModule(chunk);
}
}
} catch (MissingProvideException e) {
throw new MissingProvideException(entryPoint.getName(), e);
}
if (entryPointInput.getSourceFile().isWeak()) {
compiler.report(
JSError.make(
EXPLICIT_WEAK_ENTRY_POINT_ERROR, entryPointInput.getSourceFile().getName()));
} else {
entryPointInputs.add(entryPointInput);
}
}
} else {
Iterables.addAll(entryPointInputs, inputs);
}
return entryPointInputs;
}
@SuppressWarnings("unused")
LinkedDirectedGraph toGraphvizGraph() {
LinkedDirectedGraph graphViz = LinkedDirectedGraph.create();
for (JSChunk chunk : getAllChunks()) {
graphViz.createNode(chunk);
for (JSChunk dep : chunk.getDependencies()) {
graphViz.createNode(dep);
graphViz.connect(chunk, "->", dep);
}
}
return graphViz;
}
/**
* A chunk depth comparator that considers a deeper chunk to be "less than" a shallower chunk.
* Uses chunk names to consistently break ties.
*/
private static final class InverseDepthComparator extends Ordering {
static final InverseDepthComparator INSTANCE = new InverseDepthComparator();
@Override
public int compare(JSChunk m1, JSChunk m2) {
return depthCompare(m2, m1);
}
}
private static int depthCompare(JSChunk m1, JSChunk m2) {
if (m1 == m2) {
return 0;
}
int d1 = m1.getDepth();
int d2 = m2.getDepth();
return d1 < d2 ? -1 : d2 == d1 ? m1.getName().compareTo(m2.getName()) : 1;
}
/**
* Exception class for declaring when the chunks being fed into a JSChunkGraph as input aren't in
* dependence order, and so can't be processed for caching of various dependency-related queries.
*/
protected static class ChunkDependenceException extends IllegalArgumentException {
private static final long serialVersionUID = 1;
private final JSChunk chunk;
private final JSChunk dependentChunk;
protected ChunkDependenceException(String message, JSChunk chunk, JSChunk dependentChunk) {
super(message);
this.chunk = chunk;
this.dependentChunk = dependentChunk;
}
public JSChunk getChunk() {
return chunk;
}
public JSChunk getDependentChunk() {
return dependentChunk;
}
}
/** Another exception class */
public static class MissingChunkException extends Exception {
MissingChunkException(String chunkName) {
super(chunkName);
}
}
}