Migrate linux_doctor to null safety (#79804)

packages/flutter_tools/lib/src/linux/linux_doctor.dart

@@ -2,9 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
-import 'package:meta/meta.dart';
 import 'package:process/process.dart';
 
 import '../base/io.dart';
@@ -19,7 +16,7 @@ class _VersionInfo {
   /// This should contain a version number. For example:
   ///     "clang version 9.0.1-6+build1"
   _VersionInfo(this.description) {
-    final String versionString = RegExp(r'[0-9]+\.[0-9]+(?:\.[0-9]+)?').firstMatch(description).group(0);
+    final String? versionString = RegExp(r'[0-9]+\.[0-9]+(?:\.[0-9]+)?').firstMatch(description)?.group(0);
     number = Version.parse(versionString);
   }
 
@@ -27,14 +24,14 @@ class _VersionInfo {
   String description;
 
   // The parsed Version.
-  Version number;
+  Version? number;
 }
 
 /// A validator that checks for Clang and Make build dependencies.
 class LinuxDoctorValidator extends DoctorValidator {
   LinuxDoctorValidator({
-    @required ProcessManager processManager,
-    @required UserMessages userMessages,
+    required ProcessManager processManager,
+    required UserMessages userMessages,
   }) : _processManager = processManager,
        _userMessages = userMessages,
        super('Linux toolchain - develop for Linux desktop');
@@ -65,29 +62,30 @@ class LinuxDoctorValidator extends DoctorValidator {
     ValidationType validationType = ValidationType.installed;
     final List<ValidationMessage> messages = <ValidationMessage>[];
 
-    final Map<String, _VersionInfo> installedVersions = <String, _VersionInfo>{
+    final Map<String, _VersionInfo?> installedVersions = <String, _VersionInfo?>{
       // Sort the check to make the call order predictable for unit tests.
       for (String binary in _requiredBinaryVersions.keys.toList()..sort())
           binary: await _getBinaryVersion(binary)
     };
 
     // Determine overall validation level.
-    if (installedVersions.values.contains(null)) {
+    if (installedVersions.values.any((_VersionInfo? versionInfo) => versionInfo?.number == null)) {
       validationType = ValidationType.missing;
     } else if (installedVersions.keys.any((String binary) =>
-          installedVersions[binary].number < _requiredBinaryVersions[binary])) {
+          installedVersions[binary]!.number! < _requiredBinaryVersions[binary]!)) {
       validationType = ValidationType.partial;
     }
 
     // Message for Clang.
     {
-      final _VersionInfo version = installedVersions[kClangBinary];
-      if (version == null) {
+      final _VersionInfo? version = installedVersions[kClangBinary];
+      if (version == null || version.number == null) {
         messages.add(ValidationMessage.error(_userMessages.clangMissing));
       } else {
+        assert(_requiredBinaryVersions.containsKey(kClangBinary));
         messages.add(ValidationMessage(version.description));
-        final Version requiredVersion = _requiredBinaryVersions[kClangBinary];
-        if (version.number < requiredVersion) {
+        final Version requiredVersion = _requiredBinaryVersions[kClangBinary]!;
+        if (version.number! < requiredVersion) {
           messages.add(ValidationMessage.error(_userMessages.clangTooOld(requiredVersion.toString())));
         }
       }
@@ -95,13 +93,14 @@ class LinuxDoctorValidator extends DoctorValidator {
 
     // Message for CMake.
     {
-      final _VersionInfo version = installedVersions[kCmakeBinary];
-      if (version == null) {
+      final _VersionInfo? version = installedVersions[kCmakeBinary];
+      if (version == null || version.number == null) {
         messages.add(ValidationMessage.error(_userMessages.cmakeMissing));
       } else {
+        assert(_requiredBinaryVersions.containsKey(kCmakeBinary));
         messages.add(ValidationMessage(version.description));
-        final Version requiredVersion = _requiredBinaryVersions[kCmakeBinary];
-        if (version.number < requiredVersion) {
+        final Version requiredVersion = _requiredBinaryVersions[kCmakeBinary]!;
+        if (version.number! < requiredVersion) {
           messages.add(ValidationMessage.error(_userMessages.cmakeTooOld(requiredVersion.toString())));
         }
       }
@@ -109,14 +108,15 @@ class LinuxDoctorValidator extends DoctorValidator {
 
     // Message for ninja.
     {
-      final _VersionInfo version = installedVersions[kNinjaBinary];
-      if (version == null) {
+      final _VersionInfo? version = installedVersions[kNinjaBinary];
+      if (version == null || version.number == null) {
         messages.add(ValidationMessage.error(_userMessages.ninjaMissing));
       } else {
+        assert(_requiredBinaryVersions.containsKey(kNinjaBinary));
         // The full version description is just the number, so add context.
         messages.add(ValidationMessage(_userMessages.ninjaVersion(version.description)));
-        final Version requiredVersion = _requiredBinaryVersions[kNinjaBinary];
-        if (version.number < requiredVersion) {
+        final Version requiredVersion = _requiredBinaryVersions[kNinjaBinary]!;
+        if (version.number! < requiredVersion) {
           messages.add(ValidationMessage.error(_userMessages.ninjaTooOld(requiredVersion.toString())));
         }
       }
@@ -124,14 +124,15 @@ class LinuxDoctorValidator extends DoctorValidator {
 
     // Message for pkg-config.
     {
-      final _VersionInfo version = installedVersions[kPkgConfigBinary];
-      if (version == null) {
+      final _VersionInfo? version = installedVersions[kPkgConfigBinary];
+      if (version == null || version.number == null) {
         messages.add(ValidationMessage.error(_userMessages.pkgConfigMissing));
       } else {
+        assert(_requiredBinaryVersions.containsKey(kPkgConfigBinary));
         // The full version description is just the number, so add context.
         messages.add(ValidationMessage(_userMessages.pkgConfigVersion(version.description)));
-        final Version requiredVersion = _requiredBinaryVersions[kPkgConfigBinary];
-        if (version.number < requiredVersion) {
+        final Version requiredVersion = _requiredBinaryVersions[kPkgConfigBinary]!;
+        if (version.number! < requiredVersion) {
           messages.add(ValidationMessage.error(_userMessages.pkgConfigTooOld(requiredVersion.toString())));
         }
       }
@@ -159,8 +160,8 @@ class LinuxDoctorValidator extends DoctorValidator {
   ///
   /// Requires tha [binary] take a '--version' flag, and print a version of the
   /// form x.y.z somewhere on the first line of output.
-  Future<_VersionInfo> _getBinaryVersion(String binary) async {
-    ProcessResult result;
+  Future<_VersionInfo?> _getBinaryVersion(String binary) async {
+    ProcessResult? result;
     try {
       result = await _processManager.run(<String>[
         binary,
@@ -178,7 +179,7 @@ class LinuxDoctorValidator extends DoctorValidator {
 
   /// Checks that [library] is available via pkg-config.
   Future<bool> _libraryIsPresent(String library) async {
-    ProcessResult result;
+    ProcessResult? result;
     try {
       result = await _processManager.run(<String>[
         'pkg-config',

packages/flutter_tools/test/general.shard/linux/linux_doctor_test.dart

@@ -236,6 +236,30 @@ void main() {
     ]);
   });
 
+  testWithoutContext('Missing validation when CMake version is unparsable', () async {
+    final ProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
+      _clangPresentCommand('4.0.1'),
+      _cmakePresentCommand('bogus'),
+      _ninjaPresentCommand('1.10.0'),
+      _pkgConfigPresentCommand('0.29'),
+      ..._gtkLibrariesPresentCommands(),
+    ]);
+    final UserMessages userMessages = UserMessages();
+    final DoctorValidator linuxDoctorValidator = LinuxDoctorValidator(
+      processManager: processManager,
+      userMessages: userMessages,
+    );
+    final ValidationResult result = await linuxDoctorValidator.validate();
+
+    expect(result.type, ValidationType.missing);
+    expect(result.messages, <ValidationMessage>[
+      const ValidationMessage('clang version 4.0.1-6+build1'),
+      ValidationMessage.error(userMessages.cmakeMissing),
+      const ValidationMessage('ninja version 1.10.0'),
+      const ValidationMessage('pkg-config version 0.29'),
+    ]);
+  });
+
   testWithoutContext('Missing validation when clang++ is not available', () async {
     final ProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
       _missingBinaryCommand('clang++'),
@@ -260,6 +284,30 @@ void main() {
     ]);
   });
 
+  testWithoutContext('Missing validation when clang++ version is unparsable', () async {
+    final ProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
+      _clangPresentCommand('bogus'),
+      _cmakePresentCommand('3.16.3'),
+      _ninjaPresentCommand('1.10.0'),
+      _pkgConfigPresentCommand('0.29'),
+      ..._gtkLibrariesPresentCommands(),
+    ]);
+    final UserMessages userMessages = UserMessages();
+    final DoctorValidator linuxDoctorValidator = LinuxDoctorValidator(
+      processManager: processManager,
+      userMessages: userMessages,
+    );
+    final ValidationResult result = await linuxDoctorValidator.validate();
+
+    expect(result.type, ValidationType.missing);
+    expect(result.messages, <ValidationMessage>[
+      ValidationMessage.error(userMessages.clangMissing),
+      const ValidationMessage('cmake version 3.16.3'),
+      const ValidationMessage('ninja version 1.10.0'),
+      const ValidationMessage('pkg-config version 0.29'),
+    ]);
+  });
+
   testWithoutContext('Missing validation when ninja is not available', () async {
     final ProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
       _clangPresentCommand('4.0.1'),
@@ -284,6 +332,30 @@ void main() {
     ]);
   });
 
+  testWithoutContext('Missing validation when ninja version is unparsable', () async {
+    final ProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
+      _clangPresentCommand('4.0.1'),
+      _cmakePresentCommand('3.16.3'),
+      _ninjaPresentCommand('bogus'),
+      _pkgConfigPresentCommand('0.29'),
+      ..._gtkLibrariesPresentCommands(),
+    ]);
+    final UserMessages userMessages = UserMessages();
+    final DoctorValidator linuxDoctorValidator = LinuxDoctorValidator(
+      processManager: processManager,
+      userMessages: userMessages,
+    );
+    final ValidationResult result = await linuxDoctorValidator.validate();
+
+    expect(result.type, ValidationType.missing);
+    expect(result.messages, <ValidationMessage>[
+      const ValidationMessage('clang version 4.0.1-6+build1'),
+      const ValidationMessage('cmake version 3.16.3'),
+      ValidationMessage.error(userMessages.ninjaMissing),
+      const ValidationMessage('pkg-config version 0.29'),
+    ]);
+  });
+
   testWithoutContext('Missing validation when pkg-config is not available', () async {
     final ProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
       _clangPresentCommand('4.0.1'),
@@ -308,6 +380,30 @@ void main() {
     ]);
   });
 
+  testWithoutContext('Missing validation when pkg-config version is unparsable', () async {
+    final ProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
+      _clangPresentCommand('4.0.1'),
+      _cmakePresentCommand('3.16.3'),
+      _ninjaPresentCommand('1.10.0'),
+      _pkgConfigPresentCommand('bogus'),
+      ..._gtkLibrariesPresentCommands(),
+    ]);
+    final UserMessages userMessages = UserMessages();
+    final DoctorValidator linuxDoctorValidator = LinuxDoctorValidator(
+      processManager: processManager,
+      userMessages: userMessages,
+    );
+    final ValidationResult result = await linuxDoctorValidator.validate();
+
+    expect(result.type, ValidationType.missing);
+    expect(result.messages, <ValidationMessage>[
+      const ValidationMessage('clang version 4.0.1-6+build1'),
+      const ValidationMessage('cmake version 3.16.3'),
+      const ValidationMessage('ninja version 1.10.0'),
+      ValidationMessage.error(userMessages.pkgConfigMissing),
+    ]);
+  });
+
   testWithoutContext('Missing validation when GTK libraries are not available', () async {
     final ProcessManager processManager = FakeProcessManager.list(<FakeCommand>[
       _clangPresentCommand('4.0.1'),