bugfix: stage symlinks as symlinks when creating an action directory

Before this patch, when creating an action directory, symlinks were
staged as regular files.

5 files changed, 78 insertions, 4 deletions

diff --git a/src/buildtool/execution_api/local/local_action.cpp b/src/buildtool/execution_api/local/local_action.cpp
index d42dcdd6..d3ad7fd9 100644
--- a/src/buildtool/execution_api/local/local_action.cpp
+++ b/src/buildtool/execution_api/local/local_action.cpp
@@ -185,6 +185,18 @@ auto LocalAction::StageFile(std::filesystem::path const& target_path,
         return false;
     }
 
+    if (info.type == ObjectType::Symlink) {
+        auto to =
+            FileSystemManager::ReadContentAtPath(*blob_path, ObjectType::File);
+        if (not to) {
+            logger_.Emit(LogLevel::Error,
+                         "could not read content of symlink {}",
+                         (*blob_path).string());
+            return false;
+        }
+        return FileSystemManager::CreateSymlink(*to, target_path);
+    }
+
     return FileSystemManager::CreateDirectory(target_path.parent_path()) and
            FileSystemManager::CreateFileHardlink(*blob_path, target_path);
 }
diff --git a/test/buildtool/execution_engine/executor/executor_api.test.hpp b/test/buildtool/execution_engine/executor/executor_api.test.hpp
index 30d724ea..ffee5184 100755
--- a/test/buildtool/execution_engine/executor/executor_api.test.hpp
+++ b/test/buildtool/execution_engine/executor/executor_api.test.hpp
@@ -398,11 +398,9 @@ static inline void TestUploadAndDownloadTrees(ApiFactory const& factory,
         CHECK(FileSystemManager::IsDirectory(tmpdir));
         CHECK(FileSystemManager::IsDirectory(tmpdir / "b"));
         CHECK(FileSystemManager::IsFile(tmpdir / "a"));
-        // echo command returns regular file instead of symlink
-        CHECK(FileSystemManager::IsFile(tmpdir / "b" / "a"));
+        CHECK(FileSystemManager::IsNonUpwardsSymlink(tmpdir / "b" / "a"));
         CHECK(*FileSystemManager::ReadFile(tmpdir / "a") == "foo");
-        // echo command returns regular file instead of symlink
-        CHECK(*FileSystemManager::ReadFile(tmpdir / "b" / "a") == "bar");
+        CHECK(*FileSystemManager::ReadSymlink(tmpdir / "b" / "a") == "bar");
         REQUIRE(FileSystemManager::RemoveDirectory(tmpdir, true));
     }
 
diff --git a/test/end-to-end/TARGETS b/test/end-to-end/TARGETS
index 0e81d749..be1f642f 100644
--- a/test/end-to-end/TARGETS
+++ b/test/end-to-end/TARGETS
@@ -58,6 +58,7 @@
     , [["./", "git-import", "TESTS"], "git-import"]
     , [["./", "gc", "TESTS"], "gc"]
     , [["./", "execution-service", "TESTS"], "execution-service"]
+    , [["./", "symlinks", "TESTS"], "symlinks"]
     ]
   }
 }
diff --git a/test/end-to-end/symlinks/TARGETS b/test/end-to-end/symlinks/TARGETS
new file mode 100644
index 00000000..12add451
--- /dev/null
+++ b/test/end-to-end/symlinks/TARGETS
@@ -0,0 +1,8 @@
+{ "stage-links":
+  { "type": ["end-to-end", "with remote"]
+  , "name": ["stage-links"]
+  , "test": ["stage-links.sh"]
+  , "deps": [["end-to-end", "tool-under-test"]]
+  }
+, "TESTS": {"type": "install", "tainted": ["test"], "deps": ["stage-links"]}
+}
diff --git a/test/end-to-end/symlinks/stage-links.sh b/test/end-to-end/symlinks/stage-links.sh
new file mode 100644
index 00000000..b8234d2a
--- /dev/null
+++ b/test/end-to-end/symlinks/stage-links.sh
@@ -0,0 +1,55 @@
+#!/bin/sh
+# Copyright 2023 Huawei Cloud Computing Technology Co., Ltd.
+#
+# 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.
+
+set -eu
+
+readonly JUST="${PWD}/bin/tool-under-test"
+
+touch ROOT
+cat > TARGETS <<EOF
+{ "input":
+  { "type": "generic"
+  , "out_dirs": ["."]
+  , "cmds": ["touch foo", "ln -s foo bar", "ln -s iNeXIstENt baz"]
+  }
+, "stage-links":
+  { "type": "generic"
+  , "out_dirs": ["."]
+  , "cmds":
+    [ "test -L bar || (printf \"\n\nwrong staging: bar must be a symlink\n\n\" && exit 1)"
+    , "test -L baz || (printf \"\n\nwrong staging: baz must be a symlink\n\n\" && exit 1)"
+    , "! test -e iNeXIstENt"
+    ]
+  , "deps": ["input"]
+  }
+}
+EOF
+
+ARGS="--local-build-root=.root"
+if [ "${COMPATIBLE:-}" = "YES" ]; then
+  NAME="compatible"
+  ARGS="$ARGS --compatible"
+fi
+
+REMOTE_EXECUTION_ARGS="-r ${REMOTE_EXECUTION_ADDRESS}"
+if [ "${REMOTE_EXECUTION_PROPERTIES:-}" != "" ]; then
+  REMOTE_EXECUTION_ARGS="${REMOTE_EXECUTION_ARGS} --remote-execution-property ${REMOTE_EXECUTION_PROPERTIES}"
+fi
+
+echo "test staging locally"
+${JUST} build ${ARGS} stage-links
+
+echo "test staging remotely"
+${JUST} build ${ARGS} ${REMOTE_EXECUTION_ARGS} stage-links