Stdout/Stderr redirection (#7185)

This adds new pipeline connectors called out> and err> which redirect either stdout or stderr to a file. You can also use out+err> (or err+out>) to redirect both streams into a file.

crates/nu-command/src/formats/from/nuon.rs

@@ -156,10 +156,10 @@ impl Command for FromNuon {
                 }
             } else {
                 match pipeline.elements.remove(0) {
-                    PipelineElement::Expression(expression)
-                    | PipelineElement::Redirect(expression)
-                    | PipelineElement::And(expression)
-                    | PipelineElement::Or(expression) => expression,
+                    PipelineElement::Expression(_, expression)
+                    | PipelineElement::Redirection(_, _, expression)
+                    | PipelineElement::And(_, expression)
+                    | PipelineElement::Or(_, expression) => expression,
                 }
             }
         };

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

@@ -57,6 +57,7 @@ mod print;
 mod query;
 mod random;
 mod range;
+mod redirection;
 mod reduce;
 mod reject;
 mod rename;

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

@@ -0,0 +1,66 @@
+use nu_test_support::nu;
+use nu_test_support::playground::Playground;
+
+#[cfg(not(windows))]
+#[test]
+fn redirect_err() {
+    Playground::setup("redirect_err_test", |dirs, _sandbox| {
+        let output = nu!(
+            cwd: dirs.test(),
+            "cat asdfasdfasdf.txt err> a; cat a"
+        );
+
+        assert!(output.err.contains("asdfasdfasdf.txt"));
+    })
+}
+
+#[cfg(windows)]
+#[test]
+fn redirect_err() {
+    Playground::setup("redirect_err_test", |dirs, _sandbox| {
+        let output = nu!(
+            cwd: dirs.test(),
+            "type asdfasdfasdf.txt err> a; type a"
+        );
+
+        assert!(output.err.contains("asdfasdfasdf.txt"));
+    })
+}
+
+#[cfg(not(windows))]
+#[test]
+fn redirect_outerr() {
+    Playground::setup("redirect_outerr_test", |dirs, _sandbox| {
+        let output = nu!(
+            cwd: dirs.test(),
+            "cat asdfasdfasdf.txt out+err> a; cat a"
+        );
+
+        assert!(output.err.contains("asdfasdfasdf.txt"));
+    })
+}
+
+#[cfg(windows)]
+#[test]
+fn redirect_outerr() {
+    Playground::setup("redirect_outerr_test", |dirs, _sandbox| {
+        let output = nu!(
+            cwd: dirs.test(),
+            "type asdfasdfasdf.txt out+err> a; type a"
+        );
+
+        assert!(output.err.contains("asdfasdfasdf.txt"));
+    })
+}
+
+#[test]
+fn redirect_out() {
+    Playground::setup("redirect_out_test", |dirs, _sandbox| {
+        let output = nu!(
+            cwd: dirs.test(),
+            "echo 'hello' out> a; open a"
+        );
+
+        assert!(output.out.contains("hello"));
+    })
+}