osmcode · afarber · Aug 30, 2025 · Aug 30, 2025 · Aug 30, 2025 · Aug 30, 2025
diff --git a/src/command_sort.cpp b/src/command_sort.cpp
@@ -110,6 +110,7 @@ bool CommandSort::run_single_pass() {
     osmium::ObjectPointerCollection objects;
 
     osmium::Box bounding_box;
+    osmium::io::Header merged_input_header;
 
     uint64_t buffers_count = 0;
     uint64_t buffers_size = 0;
@@ -121,6 +122,11 @@ bool CommandSort::run_single_pass() {
         osmium::io::Reader reader{file, osmium::osm_entity_bits::object};
         const osmium::io::Header header{reader.header()};
         bounding_box.extend(header.joined_boxes());
+
+        // Merge input header info for warning detection
+        for (const auto& option : header) {
+            merged_input_header.set(option.first, option.second);
+        }
         while (osmium::memory::Buffer buffer = reader.read()) {
             ++buffers_count;
             buffers_size += buffer.committed();
@@ -146,7 +152,7 @@ bool CommandSort::run_single_pass() {
 
     m_vout << "Opening output file...\n";
     osmium::io::Header header;
-    setup_header(header);
+    setup_header(header, merged_input_header);
     header.set("sorting", "Type_then_ID");
     if (bounding_box) {
         header.add_box(bounding_box);
@@ -173,18 +179,24 @@ bool CommandSort::run_multi_pass() {
     osmium::io::Writer writer{m_output_file, m_output_overwrite, m_fsync};
 
     osmium::Box bounding_box;
+    osmium::io::Header merged_input_header;
 
     m_vout << "Reading input file headers...\n";
     for (const auto& file : m_input_files) {
         osmium::io::Reader reader{file, osmium::osm_entity_bits::nothing};
         const osmium::io::Header header{reader.header()};
         bounding_box.extend(header.joined_boxes());
+
+        // Merge input header info for warning detection
+        for (const auto& option : header) {
+            merged_input_header.set(option.first, option.second);
+        }
         reader.close();
     }
 
     m_vout << "Opening output file...\n";
     osmium::io::Header header;
-    setup_header(header);
+    setup_header(header, merged_input_header);
     if (bounding_box) {
         header.add_box(bounding_box);
     }

diff --git a/src/io.cpp b/src/io.cpp
@@ -210,6 +210,21 @@ void with_osm_output::setup_header(osmium::io::Header& header) const {
     for (const auto& h : m_output_headers) {
         header.set(h);
     }
+
+    // Check if input PBF has locations_on_ways but output format won't preserve them
+    bool has_locations_on_ways = false;
+    for (const auto& option : header) {
+        if (option.first.find("pbf_optional_feature") != std::string::npos && 
+            option.second == "LocationsOnWays") {
+            has_locations_on_ways = true;
+            break;
+        }
+    }
+
+    if (has_locations_on_ways && m_output_format.find("locations_on_ways") == std::string::npos) {
+        std::cerr << "Warning! Input file contains locations on ways that will be lost in output.\n";
+        std::cerr << "Use --output-format with locations_on_ways option to preserve node locations on ways.\n";
+    }
 }
 
 void init_header(osmium::io::Header& header, const osmium::io::Header& input_header, const std::vector<std::string>& options) {
@@ -227,5 +242,20 @@ void init_header(osmium::io::Header& header, const osmium::io::Header& input_hea
 void with_osm_output::setup_header(osmium::io::Header& header, const osmium::io::Header& input_header) const {
     header.set("generator", m_generator);
     init_header(header, input_header, m_output_headers);
+
+    // Check if input PBF has locations_on_ways but output format won't preserve them
+    bool has_locations_on_ways = false;
+    for (const auto& option : input_header) {
+        if (option.first.find("pbf_optional_feature") != std::string::npos && 
+            option.second == "LocationsOnWays") {
+            has_locations_on_ways = true;
+            break;
+        }
+    }
+
+    if (has_locations_on_ways && m_output_format.find("locations_on_ways") == std::string::npos) {
+        std::cerr << "Warning! Input file contains locations on ways that will be lost in output.\n";
+        std::cerr << "Use --output-format with locations_on_ways option to preserve node locations on ways.\n";
+    }
 }
 
diff --git a/test/add-locations-to-ways/CMakeLists.txt b/test/add-locations-to-ways/CMakeLists.txt
@@ -10,9 +10,38 @@ function(check_add_locations_to_ways _name _options _input _output)
     check_output(add-locations-to-ways ${_name} "add-locations-to-ways ${_options} --generator=test --output-header=xml_josm_upload=false --output-format=xml add-locations-to-ways/${_input}" "add-locations-to-ways/${_output}")
 endfunction()
 
+function(check_add_locations_warning _name _input _format _expected_stderr)
+    set(_cmd "$<TARGET_FILE:osmium> add-locations-to-ways --no-progress --generator=test add-locations-to-ways/${_input} -f ${_format} -o ${CMAKE_BINARY_DIR}/test/add-locations-to-ways/warning-${_name}.osm --overwrite")
+    add_test(
+        NAME "add-locations-to-ways-${_name}"
+        COMMAND ${CMAKE_COMMAND}
+        -D cmd:FILEPATH=${_cmd}
+        -D dir:PATH=${PROJECT_SOURCE_DIR}/test
+        -D expected_stderr:STRING=${_expected_stderr}
+        -P ${CMAKE_SOURCE_DIR}/test/add-locations-to-ways/run_test_check_stderr.cmake
+    )
+endfunction()
+
+function(check_add_locations_no_warning _name _input _format)
+    set(_cmd "$<TARGET_FILE:osmium> add-locations-to-ways --no-progress --generator=test add-locations-to-ways/${_input} -f ${_format} -o ${CMAKE_BINARY_DIR}/test/add-locations-to-ways/no-warning-${_name}.osm --overwrite")
+    add_test(
+        NAME "add-locations-to-ways-${_name}"
+        COMMAND ${CMAKE_COMMAND}
+        -D cmd:FILEPATH=${_cmd}
+        -D dir:PATH=${PROJECT_SOURCE_DIR}/test
+        -P ${CMAKE_SOURCE_DIR}/test/add-locations-to-ways/run_test_check_no_stderr.cmake
+    )
+endfunction()
+
 check_add_locations_to_ways(taggednodes "" input.osm output.osm)
 check_add_locations_to_ways(allnodes "-n" input.osm output-n.osm)
 check_add_locations_to_ways(membernodes "--keep-member-nodes" input-rel.osm output-rel.osm)
 
+check_add_locations_warning(warning-pbf-to-xml input-with-locations.osm.pbf xml "Warning! Input file contains locations on ways that will be lost in output.")
+check_add_locations_warning(warning-pbf-to-opl input-with-locations.osm.pbf opl "Warning! Input file contains locations on ways that will be lost in output.")
+
+check_add_locations_no_warning(no-warning-pbf-to-xml input-without-locations.osm.pbf xml)
+check_add_locations_no_warning(no-warning-pbf-to-opl input-without-locations.osm.pbf opl)
+
 
 #-----------------------------------------------------------------------------
diff --git a/test/add-locations-to-ways/input-with-locations.osm.pbf b/test/add-locations-to-ways/input-with-locations.osm.pbf
diff --git a/test/add-locations-to-ways/input-without-locations.osm.pbf b/test/add-locations-to-ways/input-without-locations.osm.pbf
diff --git a/test/add-locations-to-ways/run_test_check_no_stderr.cmake b/test/add-locations-to-ways/run_test_check_no_stderr.cmake
@@ -0,0 +1,34 @@
+#
+# Runs a test command and checks that stderr is empty (no warning message).
+# Used for testing that no false positive warnings appear.
+#
+
+if(NOT cmd)
+    message(FATAL_ERROR "Variable 'cmd' not defined")
+endif()
+
+if(NOT dir)
+    message(FATAL_ERROR "Variable 'dir' not defined")
+endif()
+
+message("Executing: ${cmd}")
+separate_arguments(cmd)
+
+execute_process(
+    COMMAND ${cmd}
+    WORKING_DIRECTORY ${dir}
+    RESULT_VARIABLE _return_code
+    OUTPUT_VARIABLE _stdout
+    ERROR_VARIABLE _stderr
+)
+
+if(NOT _return_code EQUAL 0)
+    message(FATAL_ERROR "Command failed with return code ${_return_code}")
+endif()
+
+string(FIND "${_stderr}" "Warning! Input file contains locations on ways" _found_pos)
+if(NOT _found_pos EQUAL -1)
+    message(FATAL_ERROR "Unexpected warning message found in stderr output: '${_stderr}'")
+endif()
+
+message(STATUS "Test passed: No warning message found")
diff --git a/test/add-locations-to-ways/run_test_check_stderr.cmake b/test/add-locations-to-ways/run_test_check_stderr.cmake
@@ -0,0 +1,38 @@
+#
+# Runs a test command and checks that stderr contains expected warning message.
+# Used for testing warning functionality.
+#
+
+if(NOT cmd)
+    message(FATAL_ERROR "Variable 'cmd' not defined")
+endif()
+
+if(NOT dir)
+    message(FATAL_ERROR "Variable 'dir' not defined")
+endif()
+
+if(NOT expected_stderr)
+    message(FATAL_ERROR "Variable 'expected_stderr' not defined")
+endif()
+
+message("Executing: ${cmd}")
+separate_arguments(cmd)
+
+execute_process(
+    COMMAND ${cmd}
+    WORKING_DIRECTORY ${dir}
+    RESULT_VARIABLE _return_code
+    OUTPUT_VARIABLE _stdout
+    ERROR_VARIABLE _stderr
+)
+
+if(NOT _return_code EQUAL 0)
+    message(FATAL_ERROR "Command failed with return code ${_return_code}")
+endif()
+
+string(FIND "${_stderr}" "${expected_stderr}" _found_pos)
+if(_found_pos EQUAL -1)
+    message(FATAL_ERROR "Expected stderr message '${expected_stderr}' not found in stderr output: '${_stderr}'")
+endif()
+
+message(STATUS "Test passed: Found expected stderr message")
diff --git a/test/cat/CMakeLists.txt b/test/cat/CMakeLists.txt
@@ -14,6 +14,29 @@ function(check_convert _name _input _output _format)
     check_output(cat ${_name} "cat --no-progress --generator=test cat/${_input} -f ${_format}" "cat/${_output}")
 endfunction()
 
+function(check_warning _name _input _format _expected_stderr)
+    set(_cmd "$<TARGET_FILE:osmium> cat --no-progress --generator=test cat/${_input} -f ${_format} -o ${CMAKE_BINARY_DIR}/test/cat/warning-${_name}.osm --overwrite")
+    add_test(
+        NAME "cat-${_name}"
+        COMMAND ${CMAKE_COMMAND}
+        -D cmd:FILEPATH=${_cmd}
+        -D dir:PATH=${PROJECT_SOURCE_DIR}/test
+        -D expected_stderr:STRING=${_expected_stderr}
+        -P ${CMAKE_SOURCE_DIR}/test/cat/run_test_check_stderr.cmake
+    )
+endfunction()
+
+function(check_no_warning _name _input _format)
+    set(_cmd "$<TARGET_FILE:osmium> cat --no-progress --generator=test cat/${_input} -f ${_format} -o ${CMAKE_BINARY_DIR}/test/cat/no-warning-${_name}.osm --overwrite")
+    add_test(
+        NAME "cat-${_name}"
+        COMMAND ${CMAKE_COMMAND}
+        -D cmd:FILEPATH=${_cmd}
+        -D dir:PATH=${PROJECT_SOURCE_DIR}/test
+        -P ${CMAKE_SOURCE_DIR}/test/cat/run_test_check_no_stderr.cmake
+    )
+endfunction()
+
 
 #-----------------------------------------------------------------------------
 
@@ -26,5 +49,11 @@ check_convert(bzip2 input1.osm.bz2 output1.osm.opl opl)
 check_convert(pbf input1.osm.pbf output1.osm.opl opl)
 check_convert(opl output1.osm.opl output1.osm.opl opl)
 
+check_warning(warning-pbf-to-xml input-with-locations.osm.pbf xml "Warning! Input file contains locations on ways that will be lost in output.")
+check_warning(warning-pbf-to-opl input-with-locations.osm.pbf opl "Warning! Input file contains locations on ways that will be lost in output.")
+
+check_no_warning(no-warning-pbf-to-xml input-without-locations.osm.pbf xml)
+check_no_warning(no-warning-pbf-to-opl input-without-locations.osm.pbf opl)
+
 
 #-----------------------------------------------------------------------------
diff --git a/test/cat/input-with-locations.osm.pbf b/test/cat/input-with-locations.osm.pbf
diff --git a/test/cat/input-without-locations.osm.pbf b/test/cat/input-without-locations.osm.pbf
diff --git a/test/cat/run_test_check_no_stderr.cmake b/test/cat/run_test_check_no_stderr.cmake
@@ -0,0 +1,34 @@
+#
+# Runs a test command and checks that stderr is empty (no warning message).
+# Used for testing that no false positive warnings appear.
+#
+
+if(NOT cmd)
+    message(FATAL_ERROR "Variable 'cmd' not defined")
+endif()
+
+if(NOT dir)
+    message(FATAL_ERROR "Variable 'dir' not defined")
+endif()
+
+message("Executing: ${cmd}")
+separate_arguments(cmd)
+
+execute_process(
+    COMMAND ${cmd}
+    WORKING_DIRECTORY ${dir}
+    RESULT_VARIABLE _return_code
+    OUTPUT_VARIABLE _stdout
+    ERROR_VARIABLE _stderr
+)
+
+if(NOT _return_code EQUAL 0)
+    message(FATAL_ERROR "Command failed with return code ${_return_code}")
+endif()
+
+string(FIND "${_stderr}" "Warning! Input file contains locations on ways" _found_pos)
+if(NOT _found_pos EQUAL -1)
+    message(FATAL_ERROR "Unexpected warning message found in stderr output: '${_stderr}'")
+endif()
+
+message(STATUS "Test passed: No warning message found")
diff --git a/test/cat/run_test_check_stderr.cmake b/test/cat/run_test_check_stderr.cmake
@@ -0,0 +1,38 @@
+#
+# Runs a test command and checks that stderr contains expected warning message.
+# Used for testing warning functionality.
+#
+
+if(NOT cmd)
+    message(FATAL_ERROR "Variable 'cmd' not defined")
+endif()
+
+if(NOT dir)
+    message(FATAL_ERROR "Variable 'dir' not defined")
+endif()
+
+if(NOT expected_stderr)
+    message(FATAL_ERROR "Variable 'expected_stderr' not defined")
+endif()
+
+message("Executing: ${cmd}")
+separate_arguments(cmd)
+
+execute_process(
+    COMMAND ${cmd}
+    WORKING_DIRECTORY ${dir}
+    RESULT_VARIABLE _return_code
+    OUTPUT_VARIABLE _stdout
+    ERROR_VARIABLE _stderr
+)
+
+if(NOT _return_code EQUAL 0)
+    message(FATAL_ERROR "Command failed with return code ${_return_code}")
+endif()
+
+string(FIND "${_stderr}" "${expected_stderr}" _found_pos)
+if(_found_pos EQUAL -1)
+    message(FATAL_ERROR "Expected stderr message '${expected_stderr}' not found in stderr output: '${_stderr}'")
+endif()
+
+message(STATUS "Test passed: Found expected stderr message")
diff --git a/test/sort/CMakeLists.txt b/test/sort/CMakeLists.txt
@@ -16,6 +16,46 @@ function(check_sort1 _name _input _output _format)
     check_output(sort ${_name}_mp "sort --generator=test -f ${_format} -s multipass sort/${_input}" "sort/${_output}")
 endfunction()
 
+function(check_sort_warning _name _input _format _expected_stderr)
+    set(_cmd "$<TARGET_FILE:osmium> sort --no-progress --generator=test sort/${_input} -f ${_format} -o ${CMAKE_BINARY_DIR}/test/sort/warning-${_name}.osm --overwrite")
+    add_test(
+        NAME "sort-${_name}"
+        COMMAND ${CMAKE_COMMAND}
+        -D cmd:FILEPATH=${_cmd}
+        -D dir:PATH=${PROJECT_SOURCE_DIR}/test
+        -D expected_stderr:STRING=${_expected_stderr}
+        -P ${CMAKE_SOURCE_DIR}/test/sort/run_test_check_stderr.cmake
+    )
+    set(_cmd_mp "$<TARGET_FILE:osmium> sort --no-progress --generator=test -s multipass sort/${_input} -f ${_format} -o ${CMAKE_BINARY_DIR}/test/sort/warning-${_name}-mp.osm --overwrite")
+    add_test(
+        NAME "sort-${_name}-mp"
+        COMMAND ${CMAKE_COMMAND}
+        -D cmd:FILEPATH=${_cmd_mp}
+        -D dir:PATH=${PROJECT_SOURCE_DIR}/test
+        -D expected_stderr:STRING=${_expected_stderr}
+        -P ${CMAKE_SOURCE_DIR}/test/sort/run_test_check_stderr.cmake
+    )
+endfunction()
+
+function(check_sort_no_warning _name _input _format)
+    set(_cmd "$<TARGET_FILE:osmium> sort --no-progress --generator=test sort/${_input} -f ${_format} -o ${CMAKE_BINARY_DIR}/test/sort/no-warning-${_name}.osm --overwrite")
+    add_test(
+        NAME "sort-${_name}"
+        COMMAND ${CMAKE_COMMAND}
+        -D cmd:FILEPATH=${_cmd}
+        -D dir:PATH=${PROJECT_SOURCE_DIR}/test
+        -P ${CMAKE_SOURCE_DIR}/test/sort/run_test_check_no_stderr.cmake
+    )
+    set(_cmd_mp "$<TARGET_FILE:osmium> sort --no-progress --generator=test -s multipass sort/${_input} -f ${_format} -o ${CMAKE_BINARY_DIR}/test/sort/no-warning-${_name}-mp.osm --overwrite")
+    add_test(
+        NAME "sort-${_name}-mp"
+        COMMAND ${CMAKE_COMMAND}
+        -D cmd:FILEPATH=${_cmd_mp}
+        -D dir:PATH=${PROJECT_SOURCE_DIR}/test
+        -P ${CMAKE_SOURCE_DIR}/test/sort/run_test_check_no_stderr.cmake
+    )
+endfunction()
+
 
 #-----------------------------------------------------------------------------
 
@@ -32,4 +72,10 @@ check_sort1(mixed-metadata input-simple-onefile.osm output-simple-onefile.osm os
 check_sort1(history-partially-only-version input-history-partially-only-version.osm output-history-partially-only-version.osm osm)
 check_sort1(history-only-version input-history-only-version.osm output-history-only-version.osm osm)
 
+check_sort_warning(warning-pbf-to-xml input-with-locations.osm.pbf xml "Warning! Input file contains locations on ways that will be lost in output.")
+check_sort_warning(warning-pbf-to-opl input-with-locations.osm.pbf opl "Warning! Input file contains locations on ways that will be lost in output.")
+
+check_sort_no_warning(no-warning-pbf-to-xml input-without-locations.osm.pbf xml)
+check_sort_no_warning(no-warning-pbf-to-opl input-without-locations.osm.pbf opl)
+
 #-----------------------------------------------------------------------------
diff --git a/test/sort/input-with-locations.osm.pbf b/test/sort/input-with-locations.osm.pbf
diff --git a/test/sort/input-without-locations.osm.pbf b/test/sort/input-without-locations.osm.pbf