just-mr: Warn for non-content-fixed repo reached from absent main

If the main repository is marked absent, warn if during the
dependency closure computation any non-content-fixed repositories
are reached, i.e., any "file"-type repositories that are neither
implicitly nor explicitly marked "to_git". Also warn if the main
repository itself is marked absent but is not content fixed.

Add small test checking that the new warning is produced.

4 files changed, 171 insertions, 0 deletions

diff --git a/src/other_tools/just_mr/setup_utils.cpp b/src/other_tools/just_mr/setup_utils.cpp
index 07498441..864aa684 100644
--- a/src/other_tools/just_mr/setup_utils.cpp
+++ b/src/other_tools/just_mr/setup_utils.cpp
@@ -80,6 +80,57 @@ void WarnUnknownKeys(std::string const& name, ExpressionPtr const& repo_def) {
     return std::nullopt;
 }
 
+[[nodiscard]] auto IsAbsent(ExpressionPtr const& repo_def) -> bool {
+    if (repo_def.IsNotNull() and repo_def->IsMap()) {
+        if (auto repo = repo_def->Get("repository", Expression::none_t{});
+            repo.IsNotNull() and repo->IsMap()) {
+            if (auto pragma = repo->Get("pragma", Expression::none_t{});
+                pragma.IsNotNull() and pragma->IsMap()) {
+                auto absent = pragma->Get("absent", Expression::none_t{});
+                return absent.IsNotNull() and absent->IsBool() and
+                       absent->Bool();
+            }
+        }
+    }
+    return false;
+}
+
+[[nodiscard]] auto IsNotContentFixed(ExpressionPtr const& repo_def) -> bool {
+    if (not repo_def.IsNotNull() or not repo_def->IsMap()) {
+        return false;
+    }
+    if (auto repo = repo_def->Get("repository", Expression::none_t{});
+        repo.IsNotNull() and repo->IsMap()) {
+        // Check if type == "file"
+        auto type = repo->Get("type", Expression::none_t{});
+        if (not type.IsNotNull() or not type->IsString()) {
+            return false;
+        }
+        if (type->String() == "file") {
+            auto pragma = repo->Get("pragma", Expression::none_t{});
+            if (not pragma.IsNotNull() or not pragma->IsMap()) {
+                return true;  // not content-fixed if not to_git
+            }
+            // Check for explicit to_git == true
+            if (auto to_git = pragma->Get("to_git", Expression::none_t{});
+                to_git.IsNotNull() and to_git->IsBool() and to_git->Bool()) {
+                return false;
+            }
+            // Check for implicit to_git == true
+            if (auto special = pragma->Get("special", Expression::none_t{});
+                special.IsNotNull() and special->IsString()) {
+                auto const& special_str = special->String();
+                if (special_str == "resolve-partially" or
+                    special_str == "resolve-completely") {
+                    return false;
+                }
+            }
+            return true;  // not content-fixed if not to_git
+        }
+    }
+    return false;
+}
+
 }  // namespace
 
 namespace JustMR::Utils {
@@ -92,6 +143,8 @@ void ReachableRepositories(
     std::unordered_set<std::string> include_repos_set;
     std::unordered_set<std::string> setup_repos_set;
 
+    bool absent_main = IsAbsent(repos->Get(main, Expression::none_t{}));
+
     // traverse all bindings of main repository
     for (std::queue<std::string> to_process({main}); not to_process.empty();
          to_process.pop()) {
@@ -108,6 +161,16 @@ void ReachableRepositories(
         }
         WarnUnknownKeys(repo_name, repos_repo_name);
 
+        // Warn if main repo is marked absent and current repo (including main)
+        // is not content-fixed
+        if (absent_main and IsNotContentFixed(repos_repo_name)) {
+            Logger::Log(LogLevel::Warning,
+                        "Found non-content-fixed repository {} as dependency "
+                        "of absent main repository {}",
+                        nlohmann::json(repo_name).dump(),
+                        nlohmann::json(main).dump());
+        }
+
         // If the current repo is a computed one, process its target repo
         if (auto precomputed = GetTargetRepoIfPrecomputed(repos, repo_name)) {
             to_process.push(*std::move(precomputed));
diff --git a/src/other_tools/just_mr/setup_utils.hpp b/src/other_tools/just_mr/setup_utils.hpp
index 6b0d8731..7dc482e6 100644
--- a/src/other_tools/just_mr/setup_utils.hpp
+++ b/src/other_tools/just_mr/setup_utils.hpp
@@ -63,6 +63,8 @@ struct SetupRepos {
 namespace Utils {
 
 /// \brief Get the repo dependency closure for a given main repository.
+/// If main repository is absent, emits a warning for any reachable
+/// non-content-fixed repository found.
 /// \param repos ExpressionPtr of Map type.
 void ReachableRepositories(
     ExpressionPtr const& repos,
diff --git a/test/end-to-end/just-mr/TARGETS b/test/end-to-end/just-mr/TARGETS
index a4c0b402..426b2889 100644
--- a/test/end-to-end/just-mr/TARGETS
+++ b/test/end-to-end/just-mr/TARGETS
@@ -110,6 +110,12 @@
   , "deps": [["", "mr-tool-under-test"], ["", "tool-under-test"]]
   , "repos": ["fetch-absent (data)"]
   }
+, "absent-closure":
+  { "type": ["@", "rules", "shell/test", "script"]
+  , "name": ["absent-closure"]
+  , "test": ["absent-closure.sh"]
+  , "deps": [["", "mr-tool-under-test"]]
+  }
 , "absent-config":
   { "type": ["end-to-end", "with serve"]
   , "name": ["absent-config"]
@@ -288,6 +294,7 @@
               }
             , [ "fetch-absent"
               , "fetch-absent-git-tree"
+              , "absent-closure"
               , "absent-config"
               , "fetch-absent-archives"
               , "fetch-absent-archives-symlinks"
diff --git a/test/end-to-end/just-mr/absent-closure.sh b/test/end-to-end/just-mr/absent-closure.sh
new file mode 100644
index 00000000..c4b745cc
--- /dev/null
+++ b/test/end-to-end/just-mr/absent-closure.sh
@@ -0,0 +1,99 @@
+#!/bin/sh
+# Copyright 2025 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.
+
+###
+# Test that users are warned if a non-absent repository is reached from an
+# absent main repository.
+##
+
+set -eu
+
+readonly JUST_MR="${PWD}/bin/mr-tool-under-test"
+readonly FILE_ROOT="${TEST_TMPDIR}/file-repos"
+readonly TEST_ROOT="${TEST_TMPDIR}/test-root"
+readonly LBR="${TEST_TMPDIR}/local-build-root"
+readonly OUT="${TEST_TMPDIR}/out"
+mkdir -p "${OUT}"
+
+# Set up file repos
+mkdir -p "${FILE_ROOT}/test_dir1"
+echo test > "${FILE_ROOT}/test_dir1/test_file"
+mkdir -p "${FILE_ROOT}/test_dir2/inner_dir"
+echo test > "${FILE_ROOT}/test_dir2/inner_dir/test_file"
+mkdir -p "${FILE_ROOT}/test_dir3/inner_dir"
+echo test > "${FILE_ROOT}/test_dir3/inner_dir/test_file"
+
+# Setup sample repository config
+mkdir -p "${TEST_ROOT}"
+cd "${TEST_ROOT}"
+touch ROOT
+cat > repos.json <<EOF
+{ "repositories":
+  { "main":
+    { "repository":
+      { "type": "file"
+      , "path": "."
+      , "pragma": {"absent": true}
+      }
+    , "bindings":
+      { "dep1": "file_repo_not_content_fixed"
+      , "dep2": "file_repo_to_git_explicit"
+      , "dep3": "file_repo_to_git_implicit"
+      }
+    }
+  , "file_repo_not_content_fixed":
+    { "repository":
+      { "type": "file"
+      , "path": "${FILE_ROOT}/test_dir1"
+      }
+    }
+  , "file_repo_to_git_explicit":
+    { "repository":
+      { "type": "file"
+      , "path": "${FILE_ROOT}/test_dir2"
+      , "pragma": {"to_git": true}
+      }
+    }
+  , "file_repo_to_git_implicit":
+    { "repository":
+      { "type": "file"
+      , "path": "${FILE_ROOT}/test_dir3"
+      , "pragma": {"special": "resolve-partially"}
+      }
+    }
+  }
+}
+EOF
+echo "Repository configuration:"
+cat repos.json
+
+echo
+echo Run setup of absent main repository
+echo
+"${JUST_MR}" --norc --local-build-root "${LBR}" -f "${OUT}/log.txt" setup main 2>&1
+
+echo
+echo Check expected warnings
+echo
+
+grep 'WARN.* "main" .*absent.* "main"' "${OUT}/log.txt"
+grep 'WARN.* "file_repo_not_content_fixed" .*absent.* "main"' "${OUT}/log.txt"
+grep 'WARN.* "file_repo_to_git_explicit" .*absent.* "main"' "${OUT}/log.txt" &&
+    echo "should have failed" && exit 1 || :
+grep 'WARN.* "file_repo_to_git_implicit" .*absent.* "main"' "${OUT}/log.txt" &&
+    echo "should have failed" && exit 1 || :
+
+echo
+echo OK