experiments: add --no-pager option for exp show (#4345)

dvc/command/experiments.py

@@ -59,7 +59,9 @@ def _collect_rows(
                 item = {fname: item}
             for name in names:
                 if name in item:
-                    row.append(str(_round(item[name])))
+                    value = item[name]
+                    text = str(_round(value)) if value is not None else "-"
+                    row.append(text)
                 else:
                     row.append("-")
 
@@ -88,9 +90,9 @@ def _show_experiments(all_experiments, console, precision=None):
     metric_names, param_names = _collect_names(all_experiments)
 
     table = Table()
-    table.add_column("Experiment")
+    table.add_column("Experiment", no_wrap=True)
     for name in metric_names:
-        table.add_column(name, justify="right")
+        table.add_column(name, justify="right", no_wrap=True)
     for name in param_names:
         table.add_column(name, justify="left")
 
@@ -125,15 +127,19 @@ class CmdExperimentsShow(CmdBase):
                 all_commits=self.args.all_commits,
             )
 
-            # Note: rich does not currently include a native way to force
-            # infinite width for use with a pager
-            console = Console(
-                file=io.StringIO(), force_terminal=True, width=9999
-            )
+            if self.args.no_pager:
+                console = Console()
+            else:
+                # Note: rich does not currently include a native way to force
+                # infinite width for use with a pager
+                console = Console(
+                    file=io.StringIO(), force_terminal=True, width=9999
+                )
 
             _show_experiments(all_experiments, console)
 
-            pager(console.file.getvalue())
+            if not self.args.no_pager:
+                pager(console.file.getvalue())
         except DvcException:
             logger.exception("failed to show experiments")
             return 1
@@ -273,6 +279,12 @@ def add_parser(subparsers, parent_parser):
         default=False,
         help="Show metrics for all commits.",
     )
+    experiments_show_parser.add_argument(
+        "--no-pager",
+        action="store_true",
+        default=False,
+        help="Do not pipe output into a pager.",
+    )
     experiments_show_parser.set_defaults(func=CmdExperimentsShow)
 
     EXPERIMENTS_CHECKOUT_HELP = "Checkout experiments."