bug(test-cli-fill): Use default evm-dump-dir for traces; gitignore it

.gitignore

@@ -76,6 +76,9 @@ tests/t8n_testdata
 
 fixtures/
 
+# Trace output (generated by --traces flag)
+traces/
+
 logs/
 *.log
 

docs/filling_tests/debugging_t8n_tools.md

@@ -8,7 +8,8 @@ There are two flags that can help debugging `t8n` tools or the execution-spec-te
 
 ## EVM Dump Directory
 
-The `--evm-dump-dir` flag tells the framework to write the inputs and outputs of every call made to the `t8n` command to the specified output directory. The aim is to help debugging or simply understand how a test is interacting with the EVM. Debug output is only generated when this flag is explicitly specified.
+The `--evm-dump-dir` flag tells the framework to write the inputs and outputs of every call made to the `t8n` command to the specified output directory. The aim is to help debugging or simply understand how a test is interacting with the EVM.
+When `--traces` is specified without an explicit `--evm-dump-dir`, a default directory of `traces/` is used.
 
 Each test case receives its own sub-directory under the `--evm-dump-dir` that contains these files which can be easily accessed from the HTML test report generated by `fill` (located by default in the root of the `--output` directory).
 

packages/testing/src/execution_testing/cli/pytest_commands/plugins/filler/filler.py

@@ -723,6 +723,13 @@ def pytest_configure(config: pytest.Config) -> None:
         or config.getoption("optimize_gas", False)
     )
 
+    # set default for --evm-dump-dir
+    if (
+        config.collect_traces  # type: ignore[attr-defined]
+        and config.getoption("base_dump_dir")
+    ) is None:
+        config.option.base_dump_dir = "traces"
+
     # Instantiate the transition tool here to check that the binary path/trace
     # option is valid. This ensures we only raise an error once, if
     # appropriate, instead of for every test.

packages/testing/src/execution_testing/client_clis/file_utils.py

@@ -7,6 +7,8 @@
 
 from pydantic import BaseModel, RootModel
 
+from execution_testing.client_clis.cli_types import LazyAlloc
+
 
 def dump_files_to_directory(output_path: str, files: Dict[str, Any]) -> None:
     """Dump the files to the given directory."""
@@ -22,7 +24,16 @@ def dump_files_to_directory(output_path: str, files: Dict[str, Any]) -> None:
             os.makedirs(os.path.join(output_path, rel_path), exist_ok=True)
         file_path = os.path.join(output_path, file_rel_path)
         with open(file_path, "w") as f:
-            if isinstance(file_contents, BaseModel) or isinstance(
+            if isinstance(file_contents, LazyAlloc):
+                # Validate and serialize the lazy alloc
+                f.write(
+                    file_contents.get().model_dump_json(
+                        indent=4,
+                        exclude_none=True,
+                        by_alias=True,
+                    )
+                )
+            elif isinstance(file_contents, BaseModel) or isinstance(
                 file_contents, RootModel
             ):
                 f.write(