From 0fe926fb005cd49bf1aae8987901a8fd0065e7a8 Mon Sep 17 00:00:00 2001
From: Peter Huene <peter@huene.dev>
Date: Sat, 25 Jan 2025 20:41:56 -0500
Subject: [PATCH] fix: use the correct type for scatter output. (#316)

---
 wdl-engine/CHANGELOG.md                       |  4 ++
 wdl-engine/src/eval/v1/workflow.rs            |  3 +-
 wdl-engine/src/value.rs                       |  4 ++
 .../workflows/scatter-array-type/inputs.json  |  1 +
 .../workflows/scatter-array-type/outputs.json |  6 +++
 .../workflows/scatter-array-type/source.wdl   | 40 +++++++++++++++++++
 6 files changed, 57 insertions(+), 1 deletion(-)
 create mode 100644 wdl-engine/tests/workflows/scatter-array-type/inputs.json
 create mode 100644 wdl-engine/tests/workflows/scatter-array-type/outputs.json
 create mode 100644 wdl-engine/tests/workflows/scatter-array-type/source.wdl

diff --git a/wdl-engine/CHANGELOG.md b/wdl-engine/CHANGELOG.md
index b83c20690..f1e14216b 100644
--- a/wdl-engine/CHANGELOG.md
+++ b/wdl-engine/CHANGELOG.md
@@ -11,6 +11,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 * Added progress callback to `WorkflowEvaluator` ([#310](https://github.com/stjude-rust-labs/wdl/pull/310)).
 
+### Fixed
+
+* Fixed an incorrect type being used for scatter statement outputs ([#316](https://github.com/stjude-rust-labs/wdl/pull/316)).
+
 ## 0.1.0 - 01-17-2025
 
 ### Fixed
diff --git a/wdl-engine/src/eval/v1/workflow.rs b/wdl-engine/src/eval/v1/workflow.rs
index 2c29caed3..361b511b2 100644
--- a/wdl-engine/src/eval/v1/workflow.rs
+++ b/wdl-engine/src/eval/v1/workflow.rs
@@ -37,6 +37,7 @@ use wdl_analysis::document::Task;
 use wdl_analysis::document::Workflow;
 use wdl_analysis::eval::v1::WorkflowGraphBuilder;
 use wdl_analysis::eval::v1::WorkflowGraphNode;
+use wdl_analysis::types::ArrayType;
 use wdl_analysis::types::CallType;
 use wdl_analysis::types::Optional;
 use wdl_analysis::types::PrimitiveType;
@@ -287,7 +288,7 @@ impl GatherArray {
 
     /// Converts the gather array into a WDL array value.
     fn into_array(self) -> Array {
-        Array::new_unchecked(self.element_ty, self.elements)
+        Array::new_unchecked(ArrayType::new(self.element_ty).into(), self.elements)
     }
 }
 
diff --git a/wdl-engine/src/value.rs b/wdl-engine/src/value.rs
index bf382b024..a1fadfa61 100644
--- a/wdl-engine/src/value.rs
+++ b/wdl-engine/src/value.rs
@@ -1357,6 +1357,7 @@ impl Pair {
     /// Constructs a new pair without checking the given left and right conform
     /// to the given type.
     pub(crate) fn new_unchecked(ty: Type, left: Value, right: Value) -> Self {
+        assert!(ty.as_pair().is_some());
         Self {
             ty,
             values: Arc::new((left, right)),
@@ -1441,6 +1442,7 @@ impl Array {
     /// Constructs a new array without checking the given elements conform to
     /// the given type.
     pub(crate) fn new_unchecked(ty: Type, elements: Vec<Value>) -> Self {
+        assert!(ty.as_array().is_some());
         Self {
             ty,
             elements: if elements.is_empty() {
@@ -1567,6 +1569,7 @@ impl Map {
         ty: Type,
         elements: IndexMap<Option<PrimitiveValue>, Value>,
     ) -> Self {
+        assert!(ty.as_map().is_some());
         Self {
             ty,
             elements: if elements.is_empty() {
@@ -1852,6 +1855,7 @@ impl Struct {
         name: Arc<String>,
         members: Arc<IndexMap<String, Value>>,
     ) -> Self {
+        assert!(ty.as_struct().is_some());
         Self { ty, name, members }
     }
 
diff --git a/wdl-engine/tests/workflows/scatter-array-type/inputs.json b/wdl-engine/tests/workflows/scatter-array-type/inputs.json
new file mode 100644
index 000000000..9e26dfeeb
--- /dev/null
+++ b/wdl-engine/tests/workflows/scatter-array-type/inputs.json
@@ -0,0 +1 @@
+{}
\ No newline at end of file
diff --git a/wdl-engine/tests/workflows/scatter-array-type/outputs.json b/wdl-engine/tests/workflows/scatter-array-type/outputs.json
new file mode 100644
index 000000000..3d5c77c0a
--- /dev/null
+++ b/wdl-engine/tests/workflows/scatter-array-type/outputs.json
@@ -0,0 +1,6 @@
+{
+  "run.names": [
+    "sample_one",
+    "sample_three"
+  ]
+}
\ No newline at end of file
diff --git a/wdl-engine/tests/workflows/scatter-array-type/source.wdl b/wdl-engine/tests/workflows/scatter-array-type/source.wdl
new file mode 100644
index 000000000..d6fb5b473
--- /dev/null
+++ b/wdl-engine/tests/workflows/scatter-array-type/source.wdl
@@ -0,0 +1,40 @@
+## This is a test for https://github.com/stjude-rust-labs/wdl/issues/315
+## This test will output an array rather than emit a diagnostic
+
+version 1.2
+
+struct Sample {
+  String kind
+  String name
+}
+
+workflow run {
+  Array[Sample] samples = [
+    Sample {
+      kind: "normal",
+      name: "sample_one",
+    },
+    Sample {
+      kind: "tumor",
+      name: "sample_two",
+    },
+    Sample {
+      kind: "normal",
+     name: "sample_three",
+    },
+    Sample {
+      kind: "tumor",
+      name: "sample_four",
+    },
+  ]
+
+  scatter (sample in samples) {
+    if (sample.kind == "normal") {
+      String name = sample.name
+    }
+  }
+
+  output {
+    Array[String] names = select_all(name)
+  }
+}
\ No newline at end of file