/**
* Remove the targets and rules defined by {@code path} from the cache and recursively remove the
* targets and rules defined by files that transitively include {@code path} from the cache.
*
* @param path The File that has changed.
*/
private synchronized void invalidateDependents(Path path) {
// Normalize path to ensure it hashes equally with map keys.
path = normalize(path);
if (parsedBuildFiles.containsKey(path)) {
if (console.getVerbosity() == Verbosity.ALL) {
console.getStdErr().printf("Parser invalidating %s cache\n", path.toAbsolutePath());
}
// Remove all targets defined by path from cache.
for (Map<String, Object> rawRule : parsedBuildFiles.get(path)) {
BuildTarget target = parseBuildTargetFromRawRule(rawRule);
knownBuildTargets.remove(target);
}
// Remove all rules defined in path from cache.
parsedBuildFiles.removeAll(path);
// All targets have no longer been parsed and cached.
allBuildFilesParsed = false;
}
// Recursively invalidate dependents.
for (Path dependent : buildFileDependents.get(path)) {
if (!dependent.equals(path)) {
invalidateDependents(dependent);
}
}
// Dependencies will be repopulated when files are re-parsed.
buildFileDependents.removeAll(path);
}
/**
* Finds the build file responsible for the given {@link Path} and invalidates all of the cached
* rules dependent on it.
*
* @param path A {@link Path} "contained" within the build file to find and invalidate.
*/
private void invalidateContainingBuildFile(Path path) throws IOException {
String packageBuildFilePath =
buildFileTreeCache
.getInput()
.getBasePathOfAncestorTarget(
projectFilesystem.getProjectRoot().toPath().relativize(path).toString());
invalidateDependents(
projectFilesystem
.getFileForRelativePath(packageBuildFilePath + '/' + BuckConstant.BUILD_RULES_FILE_NAME)
.toPath());
}
/**
* Called when file change events are posted to the file change EventBus to invalidate cached
* build rules if required.
*/
@Subscribe
public synchronized void onFileSystemChange(WatchEvent<?> event) throws IOException {
if (console.getVerbosity() == Verbosity.ALL) {
console
.getStdErr()
.printf(
"Parser watched event %s %s\n",
event.kind(), projectFilesystem.createContextString(event));
}
if (projectFilesystem.isPathChangeEvent(event)) {
Path path = (Path) event.context();
if (isPathCreateOrDeleteEvent(event)) {
if (path.endsWith(BuckConstant.BUILD_RULES_FILE_NAME)) {
// If a build file has been added or removed, reconstruct the build file tree.
buildFileTreeCache.invalidate();
}
// Added or removed files can affect globs, so invalidate the package build file
// "containing" {@code path} unless its filename matches a temp file pattern.
if (!isTempFile(path)) {
invalidateContainingBuildFile(path);
}
}
// Invalidate the raw rules and targets dependent on this file.
invalidateDependents(path);
} else {
// Non-path change event, likely an overflow due to many change events: invalidate everything.
buildFileTreeCache.invalidate();
invalidateCache();
}
}