Test for ExpressionTool outputs validation

conformance_tests.yaml

@@ -3566,4 +3566,10 @@
       an_array_of_trues: [ true, true, true ]
       an_int: 42
 
-- $import: tests/loop/test-index.yaml
+- id: invalid_expression_tool_output
+  tool: tests/null-expression4-tool.cwl
+  doc: Test that the output objects returned by an ExpressionTool process are validated against the outputs schema.
+  should_fail: true
+  tags: [ inline_javascript, expression_tool ]
+
+- $import: tests/loop/test-index.yaml

tests/null-expression3-tool.cwl

@@ -7,6 +7,6 @@ cwlVersion: v1.3.0-dev1
 inputs: []
 
 outputs:
-  output: Any
+  output: Any?
 
 expression: "$({'output': null })"

tests/null-expression4-tool.cwl

@@ -0,0 +1,12 @@
+#!/usr/bin/env cwl-runner
+
+class: ExpressionTool
+requirements: { InlineJavascriptRequirement: {} }
+cwlVersion: v1.3.0-dev1
+
+inputs: []
+
+outputs:
+  output: Any
+
+expression: "$({'output': null })"