Create unnormalized symlinks with ctx.actions.symlink(target_path=...)

src/main/java/com/google/devtools/build/lib/analysis/BUILD

@@ -276,6 +276,7 @@ java_library(
  ":actions/substitution",
  ":actions/symlink_action",
  ":actions/template_expansion_action",
+ ":actions/unresolved_symlink_action",
  ":actions_provider",
  ":aspect_aware_attribute_mapper",
  ":aspect_collection",
@@ -1513,6 +1514,22 @@ java_library(
  ],
 )
 
+java_library(
+ name = "actions/unresolved_symlink_action",
+ srcs = ["actions/UnresolvedSymlinkAction.java"],
+ deps = [
+ "//src/main/java/com/google/devtools/build/lib/actions",
+ "//src/main/java/com/google/devtools/build/lib/actions:artifacts",
+ "//src/main/java/com/google/devtools/build/lib/collect/nestedset",
+ "//src/main/java/com/google/devtools/build/lib/util",
+ "//src/main/java/com/google/devtools/build/lib/util:detailed_exit_code",
+ "//src/main/java/com/google/devtools/build/lib/vfs",
+ "//src/main/protobuf:failure_details_java_proto",
+ "//third_party:guava",
+ "//third_party:jsr305",
+ ],
+)
+
 java_library(
  name = "buildinfo/build_info_key",
  srcs = ["buildinfo/BuildInfoKey.java"],

src/main/java/com/google/devtools/build/lib/analysis/actions/SymlinkAction.java

@@ -36,7 +36,13 @@
 import java.io.IOException;
 import javax.annotation.Nullable;
 
-/** Action to create a symbolic link. */
+/**
+ * Action to create a symlink to a known-to-exist target with alias semantics similar to a true copy
+ * of the input (if any).
+ *
+ * To create a possibly unresolved symlink to a raw path, use {@link UnresolvedSymlinkAction}
+ * instead.
+ */
 public final class SymlinkAction extends AbstractAction {
  private static final String GUID = "7f4fab4d-d0a7-4f0f-8649-1d0337a21fee";
 
@@ -152,13 +158,6 @@ public static SymlinkAction toFileset(
  owner, execPath, primaryInput, primaryOutput, progressMessage, TargetType.FILESET);
  }
 
- public static SymlinkAction createUnresolved(
- ActionOwner owner, Artifact primaryOutput, PathFragment targetPath, String progressMessage) {
- Preconditions.checkArgument(primaryOutput.isSymlink());
- return new SymlinkAction(
- owner, targetPath, null, primaryOutput, progressMessage, TargetType.OTHER);
- }
-
  /**
  * Creates a new SymlinkAction instance, where an input artifact is not present. This is useful
  * when dealing with special cases where input paths that are outside the exec root directory

src/main/java/com/google/devtools/build/lib/analysis/actions/UnresolvedSymlinkAction.java

@@ -0,0 +1,107 @@
+// Copyright 2022 The Bazel Authors. All rights reserved.
+//
+// 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.devtools.build.lib.analysis.actions;
+
+import com.google.common.collect.ImmutableSet;
+import com.google.devtools.build.lib.actions.AbstractAction;
+import com.google.devtools.build.lib.actions.ActionExecutionContext;
+import com.google.devtools.build.lib.actions.ActionExecutionException;
+import com.google.devtools.build.lib.actions.ActionKeyContext;
+import com.google.devtools.build.lib.actions.ActionOwner;
+import com.google.devtools.build.lib.actions.ActionResult;
+import com.google.devtools.build.lib.actions.Artifact;
+import com.google.devtools.build.lib.actions.Artifact.ArtifactExpander;
+import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
+import com.google.devtools.build.lib.collect.nestedset.Order;
+import com.google.devtools.build.lib.server.FailureDetails;
+import com.google.devtools.build.lib.server.FailureDetails.FailureDetail;
+import com.google.devtools.build.lib.server.FailureDetails.SymlinkAction.Code;
+import com.google.devtools.build.lib.util.DetailedExitCode;
+import com.google.devtools.build.lib.util.Fingerprint;
+import com.google.devtools.build.lib.vfs.Path;
+import java.io.IOException;
+import javax.annotation.Nullable;
+
+/**
+ * Action to create a possibly unresolved symbolic link to a raw path.
+ *
+ * To create a symlink to a known-to-exist target with alias semantics similar to a true copy of the
+ * input, use {@link SymlinkAction} instead.
+ */
+public final class UnresolvedSymlinkAction extends AbstractAction {
+ private static final String GUID = "0f302651-602c-404b-881c-58913193cfe7";
+
+ private final String target;
+ private final String progressMessage;
+
+ public UnresolvedSymlinkAction(
+ ActionOwner owner,
+ Artifact primaryOutput,
+ String target,
+ String progressMessage) {
+ super(
+ owner,
+ NestedSetBuilder.emptySet(Order.STABLE_ORDER),
+ ImmutableSet.of(primaryOutput));
+ this.target = target;
+ this.progressMessage = progressMessage;
+ }
+
+ @Override
+ public ActionResult execute(ActionExecutionContext actionExecutionContext)
+ throws ActionExecutionException {
+
+ Path outputPath = actionExecutionContext.getInputPath(getPrimaryOutput());
+ try {
+ outputPath.createSymbolicLink(target);
+ } catch (IOException e) {
+ String message =
+ String.format(
+ "failed to create symbolic link '%s' to '%s' due to I/O error: %s",
+ getPrimaryOutput().getExecPathString(), target, e.getMessage());
+ DetailedExitCode code = createDetailedExitCode(message, Code.LINK_CREATION_IO_EXCEPTION);
+ throw new ActionExecutionException(message, e, this, false, code);
+ }
+
+ return ActionResult.EMPTY;
+ }
+
+ @Override
+ protected void computeKey(
+ ActionKeyContext actionKeyContext,
+ @Nullable ArtifactExpander artifactExpander,
+ Fingerprint fp) {
+ fp.addString(GUID);
+ fp.addString(target);
+ }
+
+ @Override
+ public String getMnemonic() {
+ return "UnresolvedSymlink";
+ }
+
+ @Override
+ protected String getRawProgressMessage() {
+ return progressMessage;
+ }
+
+ private static DetailedExitCode createDetailedExitCode(String message, Code detailedCode) {
+ return DetailedExitCode.of(
+ FailureDetail.newBuilder()
+ .setMessage(message)
+ .setSymlinkAction(FailureDetails.SymlinkAction.newBuilder().setCode(detailedCode))
+ .build());
+ }
+}

src/main/java/com/google/devtools/build/lib/analysis/starlark/StarlarkActionFactory.java

@@ -48,6 +48,7 @@
 import com.google.devtools.build.lib.analysis.actions.Substitution;
 import com.google.devtools.build.lib.analysis.actions.SymlinkAction;
 import com.google.devtools.build.lib.analysis.actions.TemplateExpansionAction;
+import com.google.devtools.build.lib.analysis.actions.UnresolvedSymlinkAction;
 import com.google.devtools.build.lib.analysis.platform.PlatformInfo;
 import com.google.devtools.build.lib.collect.nestedset.Depset;
 import com.google.devtools.build.lib.collect.nestedset.Depset.TypeException;
@@ -273,7 +274,7 @@ public void symlink(
  ? (String) progressMessageUnchecked
  : "Creating symlink " + outputArtifact.getExecPathString();
 
- SymlinkAction action;
+ Action action;
  if (targetFile != Starlark.NONE) {
  if (outputArtifact.isSymlink()) {
  throw Starlark.errorf(
@@ -315,12 +316,11 @@ public void symlink(
  throw Starlark.errorf("\"is_executable\" cannot be True when using \"target_path\"");
  }
 
- action =
- SymlinkAction.createUnresolved(
- ruleContext.getActionOwner(),
- outputArtifact,
- PathFragment.create((String) targetPath),
- progressMessage);
+ action = new UnresolvedSymlinkAction(
+ ruleContext.getActionOwner(),
+ outputArtifact,
+ (String) targetPath,
+ progressMessage);
  }
  registerAction(action);
  }

src/test/shell/bazel/bazel_symlink_test.sh

@@ -428,11 +428,11 @@ EOF
  cat > a/BUILD <<'EOF'
 load(":a.bzl", "a")
 
-a(name="a", link_target="somewhere/in/my/heart")
+a(name="a", link_target="../somewhere/../in/my/heart/..")
 EOF
 
  bazel --windows_enable_symlinks build --experimental_allow_unresolved_symlinks //a:a || fail "build failed"
- assert_contains "input link is .*[/\\]somewhere/in/my/heart" bazel-bin/a/a.file
+ assert_contains "input link is ../somewhere/../in/my/heart/.." bazel-bin/a/a.file
 }
 
 function test_symlink_created_from_symlink_action() {