fix linter: duplicated label check

duplicated labels may be OK if there are filters

lib/galaxy/tool_util/linters/outputs.py

@@ -45,7 +45,14 @@ def lint_output(tool_xml, lint_ctx):
 
         label = output.attrib.get("label", "${tool.name} on ${on_string}")
         if label in labels:
-            lint_ctx.error(f"Tool output [{name}] uses duplicated label '{label}'", node=output)
+            filter_node = output.find(".//filter")
+            if filter_node is not None:
+                lint_ctx.info(
+                    f"Tool output [{name}] uses duplicated label '{label}', double check if filters imply disjoint cases",
+                    node=output
+                )
+            else:
+                lint_ctx.error(f"Tool output [{name}] uses duplicated label '{label}'", node=output)
         labels.add(label)
 
         format_set = False

test/unit/tool_util/test_tool_linters.py

@@ -538,6 +538,12 @@
     <outputs>
         <data name="valid_name" format="fasta"/>
         <data name="valid_name" format="fasta"/>
+        <data name="another_valid_name" format="fasta" label="same label may be OK if there is a filter">
+            <filter>a condition</filter>
+        </data>
+        <data name="yet_another_valid_name" format="fasta" label="same label may be OK if there is a filter">
+            <filter>another condition</filter>
+        </data>
     </outputs>
 </tool>
 """
@@ -1410,8 +1416,12 @@ def test_outputs_discover_tool_provided_metadata(lint_ctx):
 def test_outputs_duplicated_name_label(lint_ctx):
     tool_source = get_xml_tool_source(OUTPUTS_DUPLICATED_NAME_LABEL)
     run_lint(lint_ctx, outputs.lint_output, tool_source)
-    assert "2 outputs found." in lint_ctx.info_messages
-    assert len(lint_ctx.info_messages) == 1
+    assert "4 outputs found." in lint_ctx.info_messages
+    assert (
+        "Tool output [yet_another_valid_name] uses duplicated label 'same label may be OK if there is a filter', double check if filters imply disjoint cases"
+        in lint_ctx.info_messages
+    )
+    assert len(lint_ctx.info_messages) == 2
     assert not lint_ctx.valid_messages
     assert not lint_ctx.warn_messages
     assert "Tool output [valid_name] has duplicated name" in lint_ctx.error_messages