Port src/ changes from #181

Author: Ishirui

src/dda/tools/git.py

@@ -5,14 +5,18 @@
 
 from contextlib import contextmanager
 from functools import cached_property
-from typing import TYPE_CHECKING
+from typing import TYPE_CHECKING, Any
 
 from dda.tools.base import ExecutionContext, Tool
+from dda.utils.git.changeset import ChangeSet
 from dda.utils.git.constants import GitEnvVars
+from dda.utils.git.remote import Remote
 
 if TYPE_CHECKING:
     from collections.abc import Generator
 
+    from dda.utils.git.commit import Commit, CommitDetails
+
 
 class Git(Tool):
     """
@@ -70,3 +74,147 @@ def author_email(self) -> str:
             return env_email
 
         return self.capture(["config", "--get", "user.email"]).strip()
+
+    # === PRETEMPLATED COMMANDS === #
+    def get_remote_details(self, remote_name: str = "origin") -> Remote:
+        """
+        Get the details of the given remote for the Git repository in the current working directory.
+        The returned tuple is (org, repo, url).
+        """
+
+        remote_url = self.capture(
+            ["config", "--get", f"remote.{remote_name}.url"],
+        ).strip()
+
+        return Remote(remote_url)  # type: ignore[abstract]
+
+    def get_head_commit(self) -> Commit:
+        """
+        Get the current HEAD commit of the Git repository in the current working directory.
+        """
+        from dda.utils.git.commit import Commit
+
+        sha1 = self.capture(["rev-parse", "HEAD"]).strip()
+
+        return Commit(sha1=sha1)
+
+    def get_commit_details(self, sha1: str) -> CommitDetails:
+        """
+        Get the details of the given commit in the Git repository in the current working directory.
+        """
+        from datetime import datetime
+
+        from dda.utils.git.commit import CommitDetails
+
+        raw_details = self.capture([
+            "show",
+            "--quiet",
+            # Use a format that is easy to parse
+            # fmt: author name, author email, author date, parent SHAs, commit message body
+            "--format=%an%n%ae%n%ad%n%P%n%B",
+            "--date=iso-strict",
+            sha1,
+        ])
+        author_name, author_email, date_str, parents_str, *message_lines = raw_details.splitlines()
+
+        return CommitDetails(
+            author_name=author_name,
+            author_email=author_email,
+            datetime=datetime.fromisoformat(date_str),
+            message="\n".join(message_lines).strip().strip('"'),
+            parent_shas=list(parents_str.split()),
+        )
+
+    def _capture_diff_lines(self, *args: str, **kwargs: Any) -> list[str]:
+        diff_args = [
+            "-c",
+            "core.quotepath=false",
+            "diff",
+            "-U0",
+            "--no-color",
+            "--no-prefix",
+            "--no-renames",
+            "--no-ext-diff",
+            # "-z",
+        ]
+        return self.capture([*diff_args, *args], check=False, **kwargs).strip().splitlines()
+
+    def _compare_refs(self, ref1: str, ref2: str) -> ChangeSet:
+        return ChangeSet.generate_from_diff_output(self._capture_diff_lines(ref1, ref2))
+
+    def get_commit_changes(self, sha1: str) -> ChangeSet:
+        """
+        Get the changes of the given commit in the Git repository in the current working directory.
+        """
+        return self._compare_refs(f"{sha1}^", sha1)
+
+    def get_changes_between_commits(self, a: str, b: str) -> ChangeSet:
+        """
+        Get the changes between two commits, identified by their SHA-1 hashes.
+        """
+        return self._compare_refs(a, b)
+
+    def get_working_tree_changes(self) -> ChangeSet:
+        """
+        Get the changes in the working tree of the Git repository in the current working directory.
+        """
+        from os import environ
+
+        from dda.utils.fs import temp_file
+
+        with temp_file(suffix=".git_index") as temp_index_path:
+            # Set up environment with temporary index
+            original_env = environ.copy()
+            temp_env = original_env | {"GIT_INDEX_FILE": str(temp_index_path.resolve())}
+
+            # Populate the temporary index with HEAD
+            self.run(["read-tree", "HEAD"], env=temp_env)
+
+            # Get list of untracked files
+            untracked_files_output = self.capture(
+                ["ls-files", "--others", "--exclude-standard", "-z"], env=temp_env
+            ).strip()
+            untracked_files = [x.strip() for x in untracked_files_output.split("\0") if x.strip()]
+
+            # Add untracked files to the index with --intent-to-add
+            if untracked_files:
+                self.run(["add", "--intent-to-add", *untracked_files], env=temp_env)
+
+            # Get all changes (tracked + untracked) with a single diff command
+            diff_lines = self._capture_diff_lines("HEAD", env=temp_env)
+
+            return ChangeSet.generate_from_diff_output(diff_lines)
+
+    def get_merge_base(self, remote_name: str = "origin") -> str:
+        """
+        Get the merge base of the current branch.
+        """
+        res = self.capture(["merge-base", "HEAD", remote_name], check=False).strip()
+        if not res:
+            self.app.display_warning("Could not determine merge base for current branch. Using `main` instead.")
+            return "main"
+        return res
+
+    def get_changes_with_base(
+        self,
+        base: str | None = None,
+        *,
+        include_working_tree: bool = True,
+        remote_name: str = "origin",
+    ) -> ChangeSet:
+        """
+        Get the changes with the given base.
+        By default, this base is the merge base of the current branch.
+        If it cannot be determined, `main` will be used instead.
+
+        If `include_working_tree` is True, the changes in the working tree will be included.
+        If `remote_name` is provided, the changes will be compared to the branch in the remote with this name.
+        """
+        if base is None:
+            base = self.get_merge_base(remote_name)
+
+        head = self.get_head_commit()
+        changes = ChangeSet.generate_from_diff_output(self._capture_diff_lines(base, "...", head.sha1))
+        if include_working_tree:
+            changes |= self.get_working_tree_changes()
+        return changes

src/dda/utils/fs.py

@@ -152,6 +152,30 @@ def __as_exe(self) -> Path:
         def __as_exe(self) -> Path:
             return self
 
+    @classmethod
+    def enc_hook(cls, obj: Any) -> Any:
+        if isinstance(obj, cls):
+            return repr(obj)
+
+        message = f"Objects of type {type(obj)} are not supported"
+        raise NotImplementedError(message)
+
+    @classmethod
+    def dec_hook(cls, obj_type: type, obj: Any) -> Any:
+        if obj_type is cls:
+            # Was encoded as the repr of this object
+            # Should be of the form f"{cls.__qualname__}({str(obj)})"
+            qualname, path = obj.split("(")
+            path = path.rstrip(")").strip("'").strip('"')
+            if qualname != cls.__qualname__:
+                message = f"Objects of type {obj_type} are not supported"
+                raise NotImplementedError(message)
+
+            return cls(path)
+
+        message = f"Objects of type {obj_type} are not supported"
+        raise NotImplementedError(message)
+
 
 @contextmanager
 def temp_directory() -> Generator[Path, None, None]:
@@ -170,3 +194,22 @@ def temp_directory() -> Generator[Path, None, None]:
 
     with TemporaryDirectory() as d:
         yield Path(d).resolve()
+
+
+@contextmanager
+def temp_file(suffix: str = "") -> Generator[Path, None, None]:
+    """
+    A context manager that creates a temporary file and yields a path to it. Example:
+
+    ```python
+    with temp_file() as temp_file:
+        ...
+    ```
+
+    Yields:
+        The resolved path to the temporary file, following all symlinks.
+    """
+    from tempfile import NamedTemporaryFile
+
+    with NamedTemporaryFile(suffix=suffix) as f:
+        yield Path(f.name)