[6.4.0] Cherry pick Bzlmod fixes

src/main/java/com/google/devtools/build/lib/bazel/bzlmod/BazelDepGraphFunction.java

@@ -97,7 +97,8 @@ public SkyValue compute(SkyKey skyKey, Environment env)
         throw new BazelDepGraphFunctionException(
             ExternalDepsException.withMessage(
                 Code.BAD_MODULE,
-                "Lock file is no longer up-to-date because: %s",
+                "Lock file is no longer up-to-date because: %s. "
+                    + "Please run `bazel mod deps --lockfile_mode=update` to update your lockfile.",
                 String.join(", ", diffLockfile)),
             Transience.PERSISTENT);
       }
@@ -129,6 +130,7 @@ public SkyValue compute(SkyKey skyKey, Environment env)
     if (!lockfileMode.equals(LockfileMode.OFF)) {
       BazelLockFileValue updateLockfile =
           lockfile.toBuilder()
+              .setLockFileVersion(BazelLockFileValue.LOCK_FILE_VERSION)
               .setModuleFileHash(root.getModuleFileHash())
               .setFlags(flags)
               .setLocalOverrideHashes(localOverrideHashes)
@@ -183,7 +185,7 @@ static BzlmodFlagsAndEnvVars getFlagsAndEnvVars(Environment env) throws Interrup
     ImmutableMap<String, String> moduleOverrides =
         ModuleFileFunction.MODULE_OVERRIDES.get(env).entrySet().stream()
             .collect(
-                toImmutableMap(e -> e.getKey(), e -> ((LocalPathOverride) e.getValue()).getPath()));
+                toImmutableMap(Entry::getKey, e -> ((LocalPathOverride) e.getValue()).getPath()));
 
     ImmutableList<String> yankedVersions =
         ImmutableList.copyOf(YankedVersionsUtil.ALLOWED_YANKED_VERSIONS.get(env));

src/main/java/com/google/devtools/build/lib/bazel/bzlmod/BazelLockFileFunction.java

@@ -39,13 +39,18 @@
 import com.google.gson.JsonSyntaxException;
 import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 import javax.annotation.Nullable;
 
 /** Reads the contents of the lock file into its value. */
 public class BazelLockFileFunction implements SkyFunction {
 
   public static final Precomputed<LockfileMode> LOCKFILE_MODE = new Precomputed<>("lockfile_mode");
 
+  private static final Pattern LOCKFILE_VERSION_PATTERN =
+      Pattern.compile("\"lockFileVersion\":\\s*(\\d+)");
+
   private final Path rootDirectory;
 
   private static final BzlmodFlagsAndEnvVars EMPTY_FLAGS =
@@ -95,13 +100,21 @@ public static BazelLockFileValue getLockfileValue(RootedPath lockfilePath) throw
     BazelLockFileValue bazelLockFileValue;
     try {
       String json = FileSystemUtils.readContent(lockfilePath.asPath(), UTF_8);
-      bazelLockFileValue =
-          GsonTypeAdapterUtil.createLockFileGson(
-                  lockfilePath
-                      .asPath()
-                      .getParentDirectory()
-                      .getRelative(LabelConstants.MODULE_DOT_BAZEL_FILE_NAME))
-              .fromJson(json, BazelLockFileValue.class);
+      Matcher matcher = LOCKFILE_VERSION_PATTERN.matcher(json);
+      int version = matcher.find() ? Integer.parseInt(matcher.group(1)) : -1;
+      if (version == BazelLockFileValue.LOCK_FILE_VERSION) {
+        bazelLockFileValue =
+            GsonTypeAdapterUtil.createLockFileGson(
+                    lockfilePath
+                        .asPath()
+                        .getParentDirectory()
+                        .getRelative(LabelConstants.MODULE_DOT_BAZEL_FILE_NAME))
+                .fromJson(json, BazelLockFileValue.class);
+      } else {
+        // This is an old version, needs to be updated
+        // Keep old version to recognize the problem in error mode
+        bazelLockFileValue = EMPTY_LOCKFILE.toBuilder().setLockFileVersion(version).build();
+      }
     } catch (FileNotFoundException e) {
       bazelLockFileValue = EMPTY_LOCKFILE;
     }

src/main/java/com/google/devtools/build/lib/bazel/bzlmod/BazelLockFileValue.java

@@ -92,6 +92,11 @@ public ImmutableList<String> getModuleAndFlagsDiff(
       ImmutableMap<String, String> localOverrideHashes,
       BzlmodFlagsAndEnvVars flags) {
     ImmutableList.Builder<String> moduleDiff = new ImmutableList.Builder<>();
+    if (getLockFileVersion() != BazelLockFileValue.LOCK_FILE_VERSION) {
+      return moduleDiff
+          .add("the version of the lockfile is not compatible with the current Bazel")
+          .build();
+    }
     if (!moduleFileHash.equals(getModuleFileHash())) {
       moduleDiff.add("the root MODULE.bazel has been modified");
     }

src/main/java/com/google/devtools/build/lib/bazel/bzlmod/SingleExtensionEvalFunction.java

@@ -288,7 +288,8 @@ private SingleExtensionEvalValue tryGettingValueFromLockFile(
       throw new SingleExtensionEvalFunctionException(
           ExternalDepsException.withMessage(
               Code.BAD_MODULE,
-              "Lock file is no longer up-to-date because: %s",
+              "Lock file is no longer up-to-date because: %s. "
+                  + "Please run `bazel mod deps --lockfile_mode=update` to update your lockfile.",
               String.join(", ", extDiff)),
           Transience.PERSISTENT);
     }

src/main/java/com/google/devtools/build/lib/bazel/repository/PatchUtil.java

@@ -248,7 +248,7 @@ private static ImmutableList<String> readFile(Path file) throws IOException {
   }
 
   private static void writeFile(Path file, List<String> content) throws IOException {
-    FileSystemUtils.writeLinesAs(file, UTF_8, content);
+    FileSystemUtils.writeLinesAs(file, UTF_8, content, "\n");
   }
 
   private static boolean getReadPermission(int permission) {

src/main/java/com/google/devtools/build/lib/vfs/FileSystemUtils.java

@@ -708,17 +708,17 @@ public static void writeContent(Path outputFile, byte[] content) throws IOExcept
   }
 
   /**
-   * Writes lines to file using the given encoding, ending every line with a line break '\n'
-   * character.
+   * Writes lines to file using the given encoding, ending every line with a system specific line
+   * break character.
    */
   @ThreadSafe // but not atomic
   public static void writeLinesAs(Path file, Charset charset, String... lines) throws IOException {
     writeLinesAs(file, charset, Arrays.asList(lines));
   }
 
   /**
-   * Writes lines to file using the given encoding, ending every line with a line break '\n'
-   * character.
+   * Writes lines to file using the given encoding, ending every line with a system specific line
+   * break character.
    */
   @ThreadSafe // but not atomic
   public static void writeLinesAs(Path file, Charset charset, Iterable<String> lines)
@@ -728,17 +728,28 @@ public static void writeLinesAs(Path file, Charset charset, Iterable<String> lin
   }
 
   /**
-   * Appends lines to file using the given encoding, ending every line with a line break '\n'
+   * Writes lines to file using the given encoding, ending every line with a given line break
    * character.
    */
   @ThreadSafe // but not atomic
+  public static void writeLinesAs(
+      Path file, Charset charset, Iterable<String> lines, String lineBreak) throws IOException {
+    file.getParentDirectory().createDirectoryAndParents();
+    asByteSink(file).asCharSink(charset).writeLines(lines, lineBreak);
+  }
+
+  /**
+   * Appends lines to file using the given encoding, ending every line with a system specific line
+   * break character.
+   */
+  @ThreadSafe // but not atomic
   public static void appendLinesAs(Path file, Charset charset, String... lines) throws IOException {
     appendLinesAs(file, charset, Arrays.asList(lines));
   }
 
   /**
-   * Appends lines to file using the given encoding, ending every line with a line break '\n'
-   * character.
+   * Appends lines to file using the given encoding, ending every line with a system specific line
+   * break character.
    */
   @ThreadSafe // but not atomic
   public static void appendLinesAs(Path file, Charset charset, Iterable<String> lines)

src/test/java/com/google/devtools/build/lib/bazel/bzlmod/BazelLockFileFunctionTest.java

@@ -430,7 +430,9 @@ public void invalidLockfileEmptyFile() throws Exception {
       fail(result.getError().toString());
     }
 
-    scratch.overwriteFile(rootDirectory.getRelative("MODULE.bazel.lock").getPathString(), "{}");
+    scratch.overwriteFile(
+        rootDirectory.getRelative("MODULE.bazel.lock").getPathString(),
+        "{\"lockFileVersion\": " + BazelLockFileValue.LOCK_FILE_VERSION + "}");
 
     result = evaluator.evaluate(ImmutableList.of(BazelLockFileValue.KEY), evaluationContext);
     if (!result.hasError()) {

src/test/java/com/google/devtools/build/lib/bazel/repository/starlark/StarlarkRepositoryContextTest.java

@@ -317,7 +317,7 @@ public void testPatch() throws Exception {
     context.createFile(
         context.path("my.patch"), "--- foo\n+++ foo\n" + ONE_LINE_PATCH, false, true, thread);
     context.patch(patchFile, StarlarkInt.of(0), thread);
-    testOutputFile(foo.getPath(), String.format("line one%nline two%n"));
+    testOutputFile(foo.getPath(), "line one\nline two\n");
   }
 
   @Test

src/test/py/bazel/bzlmod/bazel_lockfile_test.py

@@ -207,7 +207,8 @@ def testLockfileErrorMode(self):
             'ERROR: Error computing the main repository mapping: Lock file is'
             ' no longer up-to-date because: the root MODULE.bazel has been'
             ' modified, the value of --check_direct_dependencies flag has'
-            ' been modified'
+            ' been modified. Please run'
+            ' `bazel mod deps --lockfile_mode=update` to update your lockfile.'
         ),
         stderr,
     )
@@ -251,7 +252,8 @@ def testLocalOverrideWithErrorMode(self):
         (
             'ERROR: Error computing the main repository mapping: Lock file is'
             ' no longer up-to-date because: The MODULE.bazel file has changed'
-            ' for the overriden module: bar'
+            ' for the overriden module: bar. Please run'
+            ' `bazel mod deps --lockfile_mode=update` to update your lockfile.'
         ),
         stderr,
     )
@@ -502,7 +504,8 @@ def testUpdateModuleExtensionErrorMode(self):
             'implementation of the extension '
             "'ModuleExtensionId{bzlFileLabel=//:extension.bzl, "
             "extensionName=lockfile_ext, isolationKey=Optional.empty}' or one "
-            'of its transitive .bzl files has changed'
+            'of its transitive .bzl files has changed. Please run'
+            ' `bazel mod deps --lockfile_mode=update` to update your lockfile.'
         ),
         stderr,
     )
@@ -688,7 +691,8 @@ def testChangeEnvVariableInErrorMode(self):
             ' variables the extension'
             " 'ModuleExtensionId{bzlFileLabel=//:extension.bzl,"
             " extensionName=lockfile_ext, isolationKey=Optional.empty}' depends"
-            ' on (or their values) have changed'
+            ' on (or their values) have changed. Please run'
+            ' `bazel mod deps --lockfile_mode=update` to update your lockfile.'
         ),
         stderr,
     )
@@ -735,6 +739,40 @@ def testModuleExtensionWithFile(self):
     _, _, stderr = self.RunBazel(['build', '@hello//:all'])
     self.assertIn('I have changed now!', ''.join(stderr))
 
+  def testOldVersion(self):
+    self.ScratchFile('MODULE.bazel')
+    self.ScratchFile('BUILD', ['filegroup(name = "hello")'])
+    self.RunBazel(['build', '--nobuild', '//:all'])
+
+    # Set version to old
+    with open('MODULE.bazel.lock', 'r') as json_file:
+      data = json.load(json_file)
+    data['lockFileVersion'] = 0
+    with open('MODULE.bazel.lock', 'w') as json_file:
+      json.dump(data, json_file, indent=4)
+
+    # Run in error mode
+    exit_code, _, stderr = self.RunBazel(
+        ['build', '--nobuild', '--lockfile_mode=error', '//:all'],
+        allow_failure=True,
+    )
+    self.AssertExitCode(exit_code, 48, stderr)
+    self.assertIn(
+        (
+            'ERROR: Error computing the main repository mapping: Lock file is'
+            ' no longer up-to-date because: the version of the lockfile is not'
+            ' compatible with the current Bazel. Please run'
+            ' `bazel mod deps --lockfile_mode=update` to update your lockfile.'
+        ),
+        stderr,
+    )
+
+    # Run again with update
+    self.RunBazel(['build', '--nobuild', '//:all'])
+    with open('MODULE.bazel.lock', 'r') as json_file:
+      data = json.load(json_file)
+    self.assertEqual(data['lockFileVersion'], 1)
+
 
   def testExtensionEvaluationDoesNotRerunOnChangedImports(self):
     """