Support %workspace% in execution log paths

Previously the execution logs were always written to relative paths.
This caused an issue if you put this flag in your `.bazelrc` and
expected the log to be produced in a relative directory. You can now use
`%workspace%` to handle writing to the root of your workspace.

Fixes #22267

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

@@ -140,6 +140,7 @@ java_library(
         "//src/main/java/com/google/devtools/build/lib/util:abrupt_exit_exception",
         "//src/main/java/com/google/devtools/build/lib/util:detailed_exit_code",
         "//src/main/java/com/google/devtools/build/lib/vfs",
+        "//src/main/java/com/google/devtools/build/lib/vfs:pathfragment",
         "//src/main/protobuf:failure_details_java_proto",
         "//third_party:guava",
         "//third_party:jsr305",

src/main/java/com/google/devtools/build/lib/bazel/SpawnLogModule.java

@@ -38,6 +38,7 @@
 import com.google.devtools.build.lib.util.AbruptExitException;
 import com.google.devtools.build.lib.util.DetailedExitCode;
 import com.google.devtools.build.lib.vfs.Path;
+import com.google.devtools.build.lib.vfs.PathFragment;
 import java.io.IOException;
 import javax.annotation.Nullable;
 
@@ -94,11 +95,10 @@ private void initOutputs(CommandEnvironment env) throws IOException {
       return;
     }
 
-    Path workingDirectory = env.getWorkingDirectory();
     Path outputBase = env.getOutputBase();
 
     if (executionOptions.executionLogCompactFile != null) {
-      outputPath = workingDirectory.getRelative(executionOptions.executionLogCompactFile);
+      outputPath = getAbsolutePath(executionOptions.executionLogCompactFile, env);
 
       try {
         spawnLogContext =
@@ -121,10 +121,10 @@ private void initOutputs(CommandEnvironment env) throws IOException {
 
       if (executionOptions.executionLogBinaryFile != null) {
         encoding = Encoding.BINARY;
-        outputPath = workingDirectory.getRelative(executionOptions.executionLogBinaryFile);
+        outputPath = getAbsolutePath(executionOptions.executionLogBinaryFile, env);
       } else if (executionOptions.executionLogJsonFile != null) {
         encoding = Encoding.JSON;
-        outputPath = workingDirectory.getRelative(executionOptions.executionLogJsonFile);
+        outputPath = getAbsolutePath(executionOptions.executionLogJsonFile, env);
       }
 
       // Use a well-known temporary path to avoid accumulation of potentially large files in /tmp
@@ -144,6 +144,25 @@ private void initOutputs(CommandEnvironment env) throws IOException {
     }
   }
 
+  /**
+   * If the given path is absolute path, leave it as it is. If the given path is a relative path, it
+   * is relative to the current working directory. If the given path starts with '%workspace%, it is
+   * relative to the workspace root, which is the output of `bazel info workspace`.
+   *
+   * @return Absolute Path
+   */
+  private Path getAbsolutePath(PathFragment path, CommandEnvironment env) {
+    String pathString = path.getPathString();
+    if (env.getWorkspace() != null) {
+      pathString = pathString.replace("%workspace%", env.getWorkspace().getPathString());
+    }
+    if (!PathFragment.isAbsolute(pathString)) {
+      return env.getWorkingDirectory().getRelative(pathString);
+    }
+
+    return env.getRuntime().getFileSystem().getPath(pathString);
+  }
+
   @Override
   public void registerActionContexts(
       ModuleActionContextRegistry.Builder registryBuilder,

src/test/shell/bazel/bazel_execlog_test.sh

@@ -183,6 +183,26 @@ EOF
   grep "listedOutputs" output.json || fail "log does not contain listed outputs"
 }
 
+function test_nested_directory() {
+  mkdir d
+  cat > d/BUILD <<'EOF'
+genrule(
+      name = "action",
+      outs = ["out.txt"],
+      cmd = "echo hello > $(location out.txt)",
+      tags = ["no-remote-cache"],
+)
+EOF
+
+  cd d
+  bazel build //d:action --execution_log_json_file=%workspace%/output.json 2>&1 >> $TEST_log || fail "could not build"
+  [[ -e ../output.json ]] || fail "no json log produced"
+  bazel build //d:action --execution_log_binary_file=%workspace%/output.binary 2>&1 >> $TEST_log || fail "could not build"
+  [[ -e ../output.binary ]] || fail "no binary log produced"
+  bazel build //d:action --execution_log_compact_file=%workspace%/output.compact 2>&1 >> $TEST_log || fail "could not build"
+  [[ -e ../output.compact ]] || fail "no compact log produced"
+}
+
 function test_no_remote_cache() {
   cat > BUILD <<'EOF'
 genrule(