CMake adjustments

Author: VeaaC

flatdata-cpp/cmake/flatdata/GenerateSource.cmake

@@ -15,15 +15,19 @@ function(flatdata_generate_source TARGET_NAME SCHEMA_FILENAME OUTPUT_FILENAME)
     file(GLOB_RECURSE FLATDATA_GENERATOR_SOURCES ${FLATDATA_GENERATOR_PATH}/**/*.py)
     file(GLOB_RECURSE FLATDATA_GENERATOR_TEMPLATES ${FLATDATA_GENERATOR_PATH}/**/*.jinja2)
 
+    set(DEPFILE ${OUTPUT_FILENAME}.d)
+
     add_custom_command(
         OUTPUT ${OUTPUT_FILENAME}
         COMMAND ${PYTHON3_EXECUTABLE} ${FLATDATA_GENERATOR_PATH}/generator.py
         --gen cpp
         --schema ${SCHEMA_FILENAME}
         --output-file ${OUTPUT_FILENAME}
+        --depfile ${DEPFILE}
         DEPENDS ${FLATDATA_GENERATOR_SOURCES}
         DEPENDS ${FLATDATA_GENERATOR_TEMPLATES}
         DEPENDS ${SCHEMA_FILENAME}
+        DEPFILE ${DEPFILE}
         WORKING_DIRECTORY ${GENERATOR_PATH}
         COMMENT "Generating sources from flatdata schema"
     )

flatdata-generator/flatdata/generator/app.py

@@ -19,6 +19,7 @@
 
 from flatdata.generator.engine import Engine
 from flatdata.generator.tree.errors import FlatdataSyntaxError
+from flatdata.generator.tree.syntax_tree import SyntaxTree
 
 
 def _parse_command_line() -> argparse.Namespace:
@@ -32,6 +33,8 @@ def _parse_command_line() -> argparse.Namespace:
     parser.add_argument("-O", "--output-file", type=str, required=True,
                         default=None,
                         help="Destination file. Forces all output to be stored in one file")
+    parser.add_argument("-d", "--depfile", type=str, default=None,
+                        help="Write a Makefile-style dependency file listing all imported schemas")
     parser.add_argument("-v", "--verbose", action="store_true",
                         help="Enable verbose mode")
     parser.add_argument("--debug", action="store_true",
@@ -83,6 +86,26 @@ def _run(args: argparse.Namespace) -> None:
         output.write(output_content)
         logging.info("Code for %s is written to %s", args.gen, args.output_file)
 
+    if args.depfile:
+        _write_depfile(args.depfile, args.output_file, args.schema, engine.tree)
+
+
+def _write_depfile(depfile_path: str, output_file: str, schema_file: str,
+                   tree: 'SyntaxTree') -> None:
+    """Write a Makefile-style depfile listing all schema dependencies."""
+    deps = [os.path.abspath(schema_file)]
+    # source_file_map keys are absolute paths of all imported files
+    deps.extend(sorted(tree.source_file_map.keys()))
+
+    # Escape spaces in paths for Make syntax
+    def escape(p: str) -> str:
+        return p.replace(" ", "\\ ")
+
+    dep_str = " ".join(escape(d) for d in deps)
+    with open(depfile_path, "w") as f:
+        f.write(f"{escape(output_file)}: {dep_str}\n")
+    logging.info("Depfile written to %s", depfile_path)
+
 
 def main() -> None:
     """Entrypoint"""