feat: support line output formatting

src/git_draft/__main__.py

@@ -3,12 +3,14 @@
 from __future__ import annotations
 
 import asyncio
+import dataclasses
 import enum
 import importlib.metadata
 import logging
 import optparse
 from pathlib import Path
 import sys
+from typing import Any
 
 from .bots import load_bot
 from .common import PROGRAM, Config, UnreachableError, ensure_state_home
@@ -28,7 +30,27 @@
 _logger = logging.getLogger(__name__)
 
 
-def new_parser() -> optparse.OptionParser:
+class Accept(enum.Enum):
+    """Valid change accept mode"""
+
+    MANUAL = 0
+    MERGE = enum.auto()
+    MERGE_THEIRS = enum.auto()
+    MERGE_THEN_QUIT = enum.auto()
+
+    def merge_strategy(self) -> DraftMergeStrategy | None:
+        match self:
+            case Accept.MANUAL:
+                return None
+            case Accept.MERGE:
+                return "ignore-all-space"
+            case Accept.MERGE_THEIRS | Accept.MERGE_THEN_QUIT:
+                return "theirs"
+            case _:
+                raise UnreachableError()
+
+
+def _new_parser() -> optparse.OptionParser:
     parser = optparse.OptionParser(
         prog=PROGRAM,
         version=importlib.metadata.version("git_draft"),
@@ -94,39 +116,24 @@ def callback(
         help="edit prompt or template",
         action="store_true",
     )
-
     parser.add_option(
         "--no-accept",
         help="do not merge draft",
         dest="accept",
         action="store_const",
         const=0,
     )
+    parser.add_option(
+        "-f",
+        "--format",
+        dest="format",
+        help="formatting string",
+    )
 
     return parser
 
 
-class Accept(enum.Enum):
-    """Valid change accept mode"""
-
-    MANUAL = 0
-    MERGE = enum.auto()
-    MERGE_THEIRS = enum.auto()
-    MERGE_THEN_QUIT = enum.auto()
-
-    def merge_strategy(self) -> DraftMergeStrategy | None:
-        match self:
-            case Accept.MANUAL:
-                return None
-            case Accept.MERGE:
-                return "ignore-all-space"
-            case Accept.MERGE_THEIRS | Accept.MERGE_THEN_QUIT:
-                return "theirs"
-            case _:
-                raise UnreachableError()
-
-
-def edit(*, path: Path | None = None, text: str | None = None) -> str:
+def _edit(*, path: Path | None = None, text: str | None = None) -> str:
     if sys.stdin.isatty():
         return open_editor(text or "", path)
     # We exit with a custom code to allow the caller to act accordingly.
@@ -145,12 +152,17 @@ def edit(*, path: Path | None = None, text: str | None = None) -> str:
         sys.exit(199)
 
 
+def _format(props: Any, spec: str) -> str:
+    """Formats an instance of a dataclass using the provided pattern"""
+    return spec.format(**dataclasses.asdict(props))
+
+
 _PROMPT_PLACEHOLDER = "Enter your prompt here..."
 
 
 async def run() -> None:  # noqa: PLR0912 PLR0915
     config = Config.load()
-    (opts, args) = new_parser().parse_args()
+    (opts, args) = _new_parser().parse_args()
 
     log_path = ensure_state_home() / "log"
     if opts.log_path:
@@ -191,7 +203,7 @@ async def run() -> None:  # noqa: PLR0912 PLR0915
                     prompt = TemplatedPrompt.public(args[0], args[1:])
                 editable = opts.edit
             else:
-                prompt = edit(
+                prompt = _edit(
                     text=drafter.latest_draft_prompt() or _PROMPT_PLACEHOLDER
                 ).strip()
                 if prompt.strip() == _PROMPT_PLACEHOLDER:
@@ -212,25 +224,27 @@ async def run() -> None:  # noqa: PLR0912 PLR0915
             drafter.quit_folio()
         case "list-events":
             draft_id = args[0] if args else None
-            for line in drafter.list_draft_events(draft_id):
-                print(line)
+            spec = opts.format or "{occurred_at}\t{description}"
+            for event_props in drafter.list_draft_events(draft_id):
+                print(_format(event_props, spec))
         case "show-template":
             if len(args) != 1:
                 raise ValueError("Expected exactly one argument")
             name = args[0]
             meta = find_prompt_metadata(name)
             if opts.edit:
                 if meta:
-                    edit(path=meta.local_path(), text=meta.source())
+                    _edit(path=meta.local_path(), text=meta.source())
                 else:
-                    edit(path=PromptMetadata.local_path_for(name))
+                    _edit(path=PromptMetadata.local_path_for(name))
             else:
                 if not meta:
                     raise ValueError(f"No template named {name!r}")
                 print(meta.source())
         case "list-templates":
-            for line in list_templates():
-                print(line)
+            spec = opts.format or "{name}: {description}"
+            for template_props in list_templates():
+                print(_format(template_props, spec))
         case _:
             raise UnreachableError()
 

src/git_draft/drafter.py

@@ -452,7 +452,9 @@ def latest_draft_prompt(self) -> str | None:
             prompt = "\n\n".join([prompt, reindent(question, prefix="> ")])
         return prompt
 
-    def list_draft_events(self, draft_ref: str | None = None) -> Iterator[str]:
+    def list_draft_events(
+        self, draft_ref: str | None = None
+    ) -> Iterator[DraftEventProperties]:
         if draft_ref:
             folio_id, seqno = _parse_draft_ref(draft_ref)
         else:
@@ -469,7 +471,18 @@ def list_draft_events(self, draft_ref: str | None = None) -> Iterator[str]:
                 occurred_at, class_name, data = row
                 event = decoders[class_name].decode(data)
                 description = _format_event(event)
-                yield "\t".join([occurred_at, class_name, description])
+                yield DraftEventProperties(
+                    occurred_at, class_name, description
+                )
+
+
+@dataclasses.dataclass(frozen=True)
+class DraftEventProperties:
+    """Formattable properties corresponding to a draft's event"""
+
+    occurred_at: str
+    class_name: str
+    description: str
 
 
 @dataclasses.dataclass(frozen=True)

src/git_draft/prompt.py

@@ -210,7 +210,9 @@ def find_prompt_metadata(name: PromptName) -> PromptMetadata | None:
     return prompt.metadata
 
 
-def list_templates(*, include_local: bool = True) -> Iterator[str]:
+def list_templates(
+    *, include_local: bool = True
+) -> Iterator[TemplateProperties]:
     env = _jinja_environment(include_local=include_local)
     worktree = EmptyWorktree()
     for rel_path in env.list_templates(extensions=[_extension]):
@@ -219,5 +221,14 @@ def list_templates(*, include_local: bool = True) -> Iterator[str]:
         name, _ext = os.path.splitext(rel_path)
         prompt = _load_prompt(env, name, worktree)
         metadata = prompt.metadata
-        local = "y" if metadata.is_local() else "n"
-        yield "\t".join([name, local, metadata.description or ""])
+        scope = "local" if metadata.is_local() else "global"
+        yield TemplateProperties(name, scope, metadata.description or "")
+
+
+@dataclasses.dataclass(frozen=True)
+class TemplateProperties:
+    """Prompt template formattable properties"""
+
+    name: str
+    scope: str
+    description: str