blob: 5ee0278be94a17057a0ed694490cac3a1318708d [file] [log] [blame]
// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import '../base/error_handling_io.dart';
import '../base/file_system.dart';
import '../base/logger.dart';
/// A service for creating and parsing [Depfile]s.
class DepfileService {
DepfileService({
required Logger logger,
required FileSystem fileSystem,
}) : _logger = logger,
_fileSystem = fileSystem;
final Logger _logger;
final FileSystem _fileSystem;
static final RegExp _separatorExpr = RegExp(r'([^\\]) ');
static final RegExp _escapeExpr = RegExp(r'\\(.)');
/// Given an [depfile] File, write the depfile contents.
///
/// If both [inputs] and [outputs] are empty, ensures the file does not
/// exist. This can be overridden with the [writeEmpty] parameter when
/// both static and runtime dependencies exist and it is not desired
/// to force a rerun due to no depfile.
void writeToFile(Depfile depfile, File output, {bool writeEmpty = false}) {
if (depfile.inputs.isEmpty && depfile.outputs.isEmpty && !writeEmpty) {
ErrorHandlingFileSystem.deleteIfExists(output);
return;
}
final StringBuffer buffer = StringBuffer();
_writeFilesToBuffer(depfile.outputs, buffer);
buffer.write(': ');
_writeFilesToBuffer(depfile.inputs, buffer);
output.writeAsStringSync(buffer.toString());
}
/// Parse the depfile contents from [file].
///
/// If the syntax is invalid, returns an empty [Depfile].
Depfile parse(File file) {
final String contents = file.readAsStringSync();
final List<String> colonSeparated = contents.split(': ');
if (colonSeparated.length != 2) {
_logger.printError('Invalid depfile: ${file.path}');
return const Depfile(<File>[], <File>[]);
}
final List<File> inputs = _processList(colonSeparated[1].trim());
final List<File> outputs = _processList(colonSeparated[0].trim());
return Depfile(inputs, outputs);
}
/// Parse the output of dart2js's used dependencies.
///
/// The [file] contains a list of newline separated file URIs. The output
/// file must be manually specified.
Depfile parseDart2js(File file, File output) {
final List<File> inputs = <File>[];
for (final String rawUri in file.readAsLinesSync()) {
if (rawUri.trim().isEmpty) {
continue;
}
final Uri? fileUri = Uri.tryParse(rawUri);
if (fileUri == null) {
continue;
}
if (fileUri.scheme != 'file') {
continue;
}
inputs.add(_fileSystem.file(fileUri));
}
return Depfile(inputs, <File>[output]);
}
void _writeFilesToBuffer(List<File> files, StringBuffer buffer) {
for (final File outputFile in files) {
if (_fileSystem.path.style.separator == r'\') {
// backslashes and spaces in a depfile have to be escaped if the
// platform separator is a backslash.
final String path = outputFile.path
.replaceAll(r'\', r'\\')
.replaceAll(r' ', r'\ ');
buffer.write(' $path');
} else {
final String path = outputFile.path
.replaceAll(r' ', r'\ ');
buffer.write(' $path');
}
}
}
List<File> _processList(String rawText) {
return rawText
// Put every file on right-hand side on the separate line
.replaceAllMapped(_separatorExpr, (Match match) => '${match.group(1)}\n')
.split('\n')
// Expand escape sequences, so that '\ ', for example,ß becomes ' '
.map<String>((String path) => path.replaceAllMapped(_escapeExpr, (Match match) => match.group(1)!).trim())
.where((String path) => path.isNotEmpty)
// The tool doesn't write duplicates to these lists. This call is an attempt to
// be resilient to the outputs of other tools which write or user edits to depfiles.
.toSet()
.map(_fileSystem.file)
.toList();
}
}
/// A class for representing depfile formats.
class Depfile {
/// Create a [Depfile] from a list of [input] files and [output] files.
const Depfile(this.inputs, this.outputs);
/// The input files for this depfile.
final List<File> inputs;
/// The output files for this depfile.
final List<File> outputs;
}