Transpose now rejects streams with non-record values (#15151)

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# Description

Closes #13765

Transpose now checks if the input consists entirely of records before
doing its things, which is fine since it already `.collects()` all of
its input already.

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# User-Facing Changes
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# Tests + Formatting

Adds `rejects_non_table_stream_input` test to cover regressions.
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crates/nu-command/src/filters/transpose.rs

@@ -175,10 +175,22 @@ pub fn transpose(
 
     let metadata = input.metadata();
     let input: Vec<_> = input.into_iter().collect();
-    // Ensure error values are propagated
-    for i in input.iter() {
-        if let Value::Error { .. } = i {
-            return Ok(i.clone().into_pipeline_data_with_metadata(metadata));
+
+    // Ensure error values are propagated and non-record values are rejected
+    for value in input.iter() {
+        match value {
+            Value::Error { .. } => {
+                return Ok(value.clone().into_pipeline_data_with_metadata(metadata))
+            }
+            Value::Record { .. } => {} // go on, this is what we're looking for
+            _ => {
+                return Err(ShellError::OnlySupportsThisInputType {
+                    exp_input_type: "table or record".into(),
+                    wrong_type: "list<any>".into(),
+                    dst_span: call.head,
+                    src_span: value.span(),
+                })
+            }
         }
     }
 

crates/nu-command/tests/commands/transpose.rs

@@ -32,3 +32,11 @@ fn throw_inner_error() {
 
     assert!(actual.err.contains(error.as_str()));
 }
+
+#[test]
+fn rejects_non_table_stream_input() {
+    let actual = nu!("[1 2 3] | each { |it| ($it * 2) } | transpose | to nuon");
+
+    assert!(actual.out.is_empty());
+    assert!(actual.err.contains("only table"));
+}