Add example tests (nu-plugin-test-support) for plugins in repo (#12281)

# Description

Uses the new `nu-plugin-test-support` crate to test the examples of
commands provided by plugins in the repo.

Also fixed some of the examples to pass.

# User-Facing Changes

- Examples that are more guaranteed to work

# Tests + Formatting
- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

crates/nu_plugin_custom_values/Cargo.toml

@@ -14,3 +14,6 @@ nu-plugin = { path = "../nu-plugin", version = "0.91.1" }
 nu-protocol = { path = "../nu-protocol", version = "0.91.1", features = ["plugin"] }
 serde = { workspace = true, default-features = false }
 typetag = "0.2"
+
+[dev-dependencies]
+nu-plugin-test-support = { path = "../nu-plugin-test-support", version = "0.91.1" }

crates/nu_plugin_custom_values/src/generate.rs

@@ -29,3 +29,11 @@ impl SimplePluginCommand for Generate {
         Ok(CoolCustomValue::new("abc").into_value(call.head))
     }
 }
+
+#[test]
+fn test_examples() -> Result<(), nu_protocol::ShellError> {
+    use nu_plugin_test_support::PluginTest;
+
+    PluginTest::new("custom_values", crate::CustomValuePlugin.into())?
+        .test_command_examples(&Generate)
+}

crates/nu_plugin_custom_values/src/generate2.rs

@@ -54,3 +54,11 @@ impl SimplePluginCommand for Generate2 {
         }
     }
 }
+
+#[test]
+fn test_examples() -> Result<(), nu_protocol::ShellError> {
+    use nu_plugin_test_support::PluginTest;
+
+    PluginTest::new("custom_values", crate::CustomValuePlugin.into())?
+        .test_command_examples(&Generate2)
+}

crates/nu_plugin_custom_values/src/second_custom_value.rs

@@ -1,7 +1,9 @@
+use std::cmp::Ordering;
+
 use nu_protocol::{CustomValue, ShellError, Span, Value};
 use serde::{Deserialize, Serialize};
 
-#[derive(Clone, Debug, Serialize, Deserialize)]
+#[derive(Clone, Debug, Serialize, Deserialize, PartialEq, Eq, PartialOrd, Ord)]
 pub struct SecondCustomValue {
     pub(crate) something: String,
 }
@@ -59,6 +61,16 @@ impl CustomValue for SecondCustomValue {
         ))
     }
 
+    fn partial_cmp(&self, other: &Value) -> Option<Ordering> {
+        if let Value::CustomValue { val, .. } = other {
+            val.as_any()
+                .downcast_ref()
+                .and_then(|other: &SecondCustomValue| PartialOrd::partial_cmp(self, other))
+        } else {
+            None
+        }
+    }
+
     fn as_any(&self) -> &dyn std::any::Any {
         self
     }

crates/nu_plugin_custom_values/src/update.rs

@@ -23,9 +23,9 @@ impl SimplePluginCommand for Update {
                     result: Some(CoolCustomValue::new("abcxyz").into_value(Span::test_data())),
                 },
                 PluginExample {
-                    example: "custom-value generate | custom-value update".into(),
+                    example: "custom-value generate2 | custom-value update".into(),
                     description: "Update a SecondCustomValue".into(),
-                    result: Some(CoolCustomValue::new("xyzabc").into_value(Span::test_data())),
+                    result: Some(SecondCustomValue::new("xyzabc").into_value(Span::test_data())),
                 },
             ])
     }
@@ -56,3 +56,11 @@ impl SimplePluginCommand for Update {
         .into())
     }
 }
+
+#[test]
+fn test_examples() -> Result<(), nu_protocol::ShellError> {
+    use nu_plugin_test_support::PluginTest;
+
+    PluginTest::new("custom_values", crate::CustomValuePlugin.into())?
+        .test_command_examples(&Update)
+}