Make delimiter in rich progress bar configurable (#18372)

docs/source-pytorch/common/progress_bar.rst

@@ -92,6 +92,7 @@ Customize the theme for your :class:`~lightning.pytorch.callbacks.RichProgressBa
             time="grey82",
             processing_speed="grey82",
             metrics="grey82",
+            metrics_text_delimiter="\n",
         )
     )
 

src/lightning/pytorch/callbacks/progress/rich_progress.py

@@ -136,12 +136,13 @@ def render(self, task: "Task") -> RenderableType:
     class MetricsTextColumn(ProgressColumn):
         """A column containing text."""
 
-        def __init__(self, trainer: "pl.Trainer", style: Union[str, "Style"]):
+        def __init__(self, trainer: "pl.Trainer", style: Union[str, "Style"], text_delimiter: str):
             self._trainer = trainer
             self._tasks: Dict[Union[int, TaskID], Any] = {}
             self._current_task_id = 0
             self._metrics: Dict[Union[str, "Style"], Any] = {}
             self._style = style
+            self._text_delimiter = text_delimiter
             super().__init__()
 
         def update(self, metrics: Dict[Any, Any]) -> None:
@@ -167,7 +168,8 @@ def render(self, task: "Task") -> Text:
             if self._trainer.training and task.id != self._current_task_id:
                 return self._tasks[task.id]
 
-            text = " ".join(self._generate_metrics_texts())
+            metrics_texts = self._generate_metrics_texts()
+            text = self._text_delimiter.join(metrics_texts)
             return Text(text, justify="left", style=self._style)
 
         def _generate_metrics_texts(self) -> Generator[str, None, None]:
@@ -204,6 +206,7 @@ class RichProgressBarTheme:
     time: Union[str, Style] = "grey54"
     processing_speed: Union[str, Style] = "grey70"
     metrics: Union[str, Style] = "white"
+    metrics_text_delimiter: str = " "
 
 
 class RichProgressBar(ProgressBar):
@@ -325,7 +328,7 @@ def _init_progress(self, trainer: "pl.Trainer") -> None:
             reconfigure(**self._console_kwargs)
             self._console = get_console()
             self._console.clear_live()
-            self._metric_component = MetricsTextColumn(trainer, self.theme.metrics)
+            self._metric_component = MetricsTextColumn(trainer, self.theme.metrics, self.theme.metrics_text_delimiter)
             self.progress = CustomProgress(
                 *self.configure_columns(trainer),
                 self._metric_component,
@@ -376,7 +379,10 @@ def on_train_epoch_start(self, trainer: "pl.Trainer", pl_module: "pl.LightningMo
                 self.train_progress_bar_id = self._add_task(total_batches, train_description)
             else:
                 self.progress.reset(
-                    self.train_progress_bar_id, total=total_batches, description=train_description, visible=True
+                    self.train_progress_bar_id,
+                    total=total_batches,
+                    description=train_description,
+                    visible=True,
                 )
 
         self.refresh()
@@ -399,22 +405,30 @@ def on_validation_batch_start(
                 self.progress.update(self.val_sanity_progress_bar_id, advance=0, visible=False)
 
             self.val_sanity_progress_bar_id = self._add_task(
-                self.total_val_batches_current_dataloader, self.sanity_check_description, visible=False
+                self.total_val_batches_current_dataloader,
+                self.sanity_check_description,
+                visible=False,
             )
         else:
             if self.val_progress_bar_id is not None:
                 self.progress.update(self.val_progress_bar_id, advance=0, visible=False)
 
             # TODO: remove old tasks when new onces are created
             self.val_progress_bar_id = self._add_task(
-                self.total_val_batches_current_dataloader, self.validation_description, visible=False
+                self.total_val_batches_current_dataloader,
+                self.validation_description,
+                visible=False,
             )
 
         self.refresh()
 
     def _add_task(self, total_batches: Union[int, float], description: str, visible: bool = True) -> "TaskID":
         assert self.progress is not None
-        return self.progress.add_task(f"[{self.theme.description}]{description}", total=total_batches, visible=visible)
+        return self.progress.add_task(
+            f"[{self.theme.description}]{description}",
+            total=total_batches,
+            visible=visible,
+        )
 
     def _update(self, progress_bar_id: Optional["TaskID"], current: int, visible: bool = True) -> None:
         if self.progress is not None and self.is_enabled:
@@ -486,7 +500,12 @@ def on_predict_batch_start(
         self.refresh()
 
     def on_train_batch_end(
-        self, trainer: "pl.Trainer", pl_module: "pl.LightningModule", outputs: STEP_OUTPUT, batch: Any, batch_idx: int
+        self,
+        trainer: "pl.Trainer",
+        pl_module: "pl.LightningModule",
+        outputs: STEP_OUTPUT,
+        batch: Any,
+        batch_idx: int,
     ) -> None:
         self._update(self.train_progress_bar_id, batch_idx + 1)
         self._update_metrics(trainer, pl_module)
@@ -573,7 +592,12 @@ def _update_metrics(self, trainer: "pl.Trainer", pl_module: "pl.LightningModule"
     def teardown(self, trainer: "pl.Trainer", pl_module: "pl.LightningModule", stage: str) -> None:
         self._stop_progress()
 
-    def on_exception(self, trainer: "pl.Trainer", pl_module: "pl.LightningModule", exception: BaseException) -> None:
+    def on_exception(
+        self,
+        trainer: "pl.Trainer",
+        pl_module: "pl.LightningModule",
+        exception: BaseException,
+    ) -> None:
         self._stop_progress()
 
     def configure_columns(self, trainer: "pl.Trainer") -> list: