Introduce Patch class for cleaner API

Author: ben-edna

dfetch/commands/format_patch.py

@@ -29,8 +29,6 @@
 import pathlib
 import re
 
-import patch_ng
-
 import dfetch.commands.command
 import dfetch.manifest.project
 import dfetch.project
@@ -40,14 +38,7 @@
 from dfetch.project.subproject import SubProject
 from dfetch.project.svnsubproject import SvnSubProject
 from dfetch.util.util import catch_runtime_exceptions, in_directory
-from dfetch.vcs.patch import (
-    PatchAuthor,
-    PatchInfo,
-    add_prefix_to_patch,
-    convert_patch_to,
-    dump_patch,
-    parse_patch,
-)
+from dfetch.vcs.patch import Patch, PatchAuthor, PatchInfo, PatchType
 
 logger = get_logger(__name__)
 
@@ -112,7 +103,7 @@ def __call__(self, args: argparse.Namespace) -> None:
                         continue
 
                     version = subproject.on_disk_version()
-                    for idx, patch in enumerate(subproject.patch, start=1):
+                    for idx, patch_file in enumerate(subproject.patch, start=1):
 
                         patch_info = PatchInfo(
                             author=PatchAuthor(
@@ -125,20 +116,19 @@ def __call__(self, args: argparse.Namespace) -> None:
                             revision="" if not version else version.revision,
                         )
 
-                        corrected_patch = convert_patch_to(
-                            parse_patch(patch), _determine_target_patch_type(subproject)
+                        patch = Patch.from_file(patch_file).convert_type(
+                            _determine_target_patch_type(subproject)
                         )
-                        prefixed_patch = add_prefix_to_patch(
-                            corrected_patch,
-                            path_prefix=re.split(r"\*", subproject.source, 1)[0].rstrip(
-                                "/"
-                            ),
+                        patch.add_prefix(
+                            re.split(r"\*", subproject.source, 1)[0].rstrip("/")
                         )
 
-                        output_patch_file = output_dir_path / pathlib.Path(patch).name
+                        output_patch_file = (
+                            output_dir_path / pathlib.Path(patch_file).name
+                        )
                         output_patch_file.write_text(
-                            subproject.create_formatted_patch_header(patch_info)
-                            + dump_patch(prefixed_patch)
+                            patch.dump_header(patch_info) + patch.dump(),
+                            encoding="utf-8",
                         )
 
                         logger.print_info_line(
@@ -150,13 +140,13 @@ def __call__(self, args: argparse.Namespace) -> None:
             raise RuntimeError("\n".join(exceptions))
 
 
-def _determine_target_patch_type(subproject: SubProject) -> str:
+def _determine_target_patch_type(subproject: SubProject) -> PatchType:
     """Determine the subproject type for the patch."""
     if isinstance(subproject, GitSubProject):
-        required_type = patch_ng.GIT
+        required_type = PatchType.GIT
     elif isinstance(subproject, SvnSubProject):
-        required_type = patch_ng.SVN
+        required_type = PatchType.SVN
     else:
-        required_type = patch_ng.PLAIN
+        required_type = PatchType.PLAIN
 
-    return str(required_type)
+    return required_type

dfetch/project/gitsubproject.py

@@ -10,7 +10,6 @@
 from dfetch.project.subproject import SubProject
 from dfetch.util.util import safe_rmtree
 from dfetch.vcs.git import GitLocalRepo, GitRemote, get_git_version
-from dfetch.vcs.patch import PatchInfo
 
 logger = get_logger(__name__)
 
@@ -112,7 +111,3 @@ def _determine_fetched_version(self, version: Version, fetched_sha: str) -> Vers
     def get_default_branch(self) -> str:  # type: ignore
         """Get the default branch of this repository."""
         return self._remote_repo.get_default_branch()
-
-    def create_formatted_patch_header(self, patch_info: PatchInfo) -> str:
-        """Create a formatted patch header for the given patch info."""
-        return patch_info.to_git_header()

dfetch/project/gitsuperproject.py

@@ -18,7 +18,6 @@
 from dfetch.project.superproject import RevisionRange, SuperProject
 from dfetch.util.util import resolve_absolute_path
 from dfetch.vcs.git import GitLocalRepo
-from dfetch.vcs.patch import reverse_patch
 
 logger = get_logger(__name__)
 
@@ -138,14 +137,9 @@ def diff(
             combined_diff += [diff_since_revision]
 
         untracked_files_patch = local_repo.untracked_files_patch(ignore)
-        if untracked_files_patch:
+        if not untracked_files_patch.is_empty():
             if reverse:
-                reversed_patch = reverse_patch(untracked_files_patch.encode("utf-8"))
-                if not reversed_patch:
-                    raise RuntimeError(
-                        "Failed to reverse untracked files patch; patch parsing returned empty."
-                    )
-                untracked_files_patch = reversed_patch
-            combined_diff += [untracked_files_patch]
+                untracked_files_patch.reverse()
+            combined_diff += [untracked_files_patch.dump()]
 
         return "\n".join(combined_diff)

dfetch/project/subproject.py

@@ -13,7 +13,7 @@
 from dfetch.project.metadata import Metadata
 from dfetch.util.util import hash_directory, safe_rm
 from dfetch.util.versions import latest_tag_from_list
-from dfetch.vcs.patch import PatchInfo, apply_patch
+from dfetch.vcs.patch import Patch
 
 logger = get_logger(__name__)
 
@@ -161,7 +161,7 @@ def _apply_patches(self, count: int = -1) -> list[str]:
             normalized_patch_path = str(relative_patch_path.as_posix())
 
             self._log_project(f'Applying patch "{normalized_patch_path}"')
-            result = apply_patch(normalized_patch_path, root=self.local_path)
+            result = Patch.from_file(normalized_patch_path).apply(root=self.local_path)
 
             if result.encoding_warning:
                 self._log_project(
@@ -395,9 +395,3 @@ def is_license_file(filename: str) -> bool:
             fnmatch.fnmatch(filename.lower(), pattern)
             for pattern in SubProject.LICENSE_GLOBS
         )
-
-    @abstractmethod
-    def create_formatted_patch_header(self, patch_info: PatchInfo) -> str:
-        """Create a formatted patch header for the given patch info."""
-        del patch_info
-        return ""

dfetch/project/svnsubproject.py

@@ -13,7 +13,6 @@
     find_non_matching_files,
     safe_rm,
 )
-from dfetch.vcs.patch import PatchInfo
 from dfetch.vcs.svn import SvnRemote, SvnRepo, get_svn_version
 
 logger = get_logger(__name__)
@@ -180,7 +179,3 @@ def _get_revision(self, branch: str) -> str:
     def get_default_branch(self) -> str:
         """Get the default branch of this repository."""
         return SvnRepo.DEFAULT_BRANCH
-
-    def create_formatted_patch_header(self, patch_info: PatchInfo) -> str:
-        """Create a formatted patch header for the given patch info."""
-        return patch_info.to_svn_header()

dfetch/project/svnsuperproject.py

@@ -20,11 +20,7 @@
     in_directory,
     resolve_absolute_path,
 )
-from dfetch.vcs.patch import (
-    combine_patches,
-    create_svn_patch_for_new_file,
-    reverse_patch,
-)
+from dfetch.vcs.patch import Patch, PatchType
 from dfetch.vcs.svn import SvnRepo
 
 logger = get_logger(__name__)
@@ -116,22 +112,18 @@ def diff(
             if new:
                 new, old = old, new
 
-        filtered = repo.create_diff(old, new, ignore)
+        patch = repo.create_diff(old, new, ignore)
 
         if new:
-            return filtered
+            return patch.dump()
 
-        patches: list[bytes] = [filtered.encode("utf-8")] if filtered else []
         with in_directory(path):
-            for file_path in repo.untracked_files(".", ignore):
-                patch = create_svn_patch_for_new_file(file_path)
-                if patch:
-                    patches.append(patch.encode("utf-8"))
-
-        patch_str = combine_patches(patches)
+            patch.extend(
+                Patch.for_new_files(repo.untracked_files(".", ignore), PatchType.SVN)
+            )
 
         # SVN has no way of producing a reverse working copy patch, reverse ourselves
-        if reverse and not new:
-            patch_str = reverse_patch(patch_str.encode("UTF-8"))
+        if reverse:
+            patch.reverse()
 
-        return patch_str
+        return patch.dump()

dfetch/vcs/git.py

@@ -12,7 +12,7 @@
 from dfetch.log import get_logger
 from dfetch.util.cmdline import SubprocessCommandError, run_on_cmdline
 from dfetch.util.util import in_directory, safe_rmtree
-from dfetch.vcs.patch import create_git_patch_for_new_file
+from dfetch.vcs.patch import Patch, PatchType
 
 logger = get_logger(__name__)
 
@@ -457,7 +457,7 @@ def any_changes_or_untracked(path: str) -> bool:
                 .splitlines()
             )
 
-    def untracked_files_patch(self, ignore: Sequence[str] | None = None) -> str:
+    def untracked_files_patch(self, ignore: Sequence[str] | None = None) -> Patch:
         """Create a diff for untracked files."""
         with in_directory(self._path):
             untracked_files = (
@@ -476,10 +476,9 @@ def untracked_files_patch(self, ignore: Sequence[str] | None = None) -> str:
                 ]
 
             if untracked_files:
-                return "\n".join(
-                    [create_git_patch_for_new_file(file) for file in untracked_files]
-                )
-            return ""
+                return Patch.for_new_files(untracked_files, PatchType.GIT)
+
+            return Patch.empty()
 
     @staticmethod
     def submodules() -> list[Submodule]: