fix: stop recording the git log in the metadata (#477)

Nothing consumes the log, and there's no design for anything to consume the
log. Plus, it cluttered up synth.metadata.

synthtool/metadata.py

@@ -174,44 +174,12 @@ def __enter__(self):
         _add_self_git_source()
 
     def __exit__(self, type, value, traceback):
-        _append_git_logs(self.old_metadata, get())
         _clear_local_paths(get())
         _metadata.sources.sort(key=_source_key)
         if _enable_write_metadata:
             write(self.metadata_file_path)
 
 
-def _append_git_logs(old_metadata, new_metadata):
-    """Adds git logs to git sources in new_metadata.
-
-    Parameters:
-        old_metadata: instance of metadata_pb2.Metadata
-        old_metadata: instance of metadata_pb2.Metadata
-    """
-    old_map = _get_git_source_map(old_metadata)
-    new_map = _get_git_source_map(new_metadata)
-    git = shutil.which("git")
-    for name, git_source in new_map.items():
-        # Get the git history since the last run:
-        old_source = old_map.get(name, metadata_pb2.GitSource())
-        if not old_source.sha or not git_source.local_path:
-            continue
-        output = subprocess.run(
-            [
-                git,
-                "-C",
-                git_source.local_path,
-                "log",
-                "--pretty=%H%n%B",
-                "--no-decorate",
-                f"{old_source.sha}..HEAD",
-            ],
-            stdout=subprocess.PIPE,
-            universal_newlines=True,
-        ).stdout
-        git_source.log = output
-
-
 def _get_git_source_map(metadata) -> Dict[str, object]:
     """Gets the git sources from the metadata.
 

tests/test_metadata.py

@@ -16,7 +16,6 @@
 import os
 import pathlib
 import pytest
-import re
 import shutil
 import subprocess
 
@@ -161,7 +160,11 @@ def test_track_obsolete_files_defaults_to_false(preserve_track_obsolete_file_fla
     assert not metadata.should_track_obsolete_files()
 
 
-def test_append_git_log_to_metadata(source_tree):
+def test_used_to_append_git_log_to_metadata(source_tree):
+    """Synthtool used to append the git log for each git source.  But nothing
+    consumes the log, and there's no design for anything to consume the log.
+    Plus, it cluttered up synth.metadata.
+    """
     with metadata.MetadataTrackerAndWriter(source_tree.tmpdir / "synth.metadata"):
         # Create one commit that will be recorded in the metadata.
         source_tree.write("a")
@@ -195,12 +198,8 @@ def test_append_git_log_to_metadata(source_tree):
 
     # Read the metadata that we just wrote.
     mdata = metadata._read_or_empty(source_tree.tmpdir / "synth.metadata")
-    # Match 2 log lines.
-    assert re.match(
-        r"[0-9A-Fa-f]+\ncode/c\n+[0-9A-Fa-f]+\ncode/b\n+",
-        mdata.sources[1].git.log,
-        re.MULTILINE,
-    )
+    # The log should be empty.
+    assert "" == mdata.sources[1].git.log
     # Make sure the local path field is not recorded.
     assert not mdata.sources[0].git.local_path is None