test: add test coverage for Tools Inspector (#4700)

Co-authored-by: tlongwell-block <109685178+tlongwell-block@users.noreply.github.com>
Co-authored-by: Tyler Longwell <tlongwell@squareup.com>

crates/goose/tests/tool_inspection_manager_tests.rs

@@ -0,0 +1,111 @@
+use anyhow::{anyhow, Result};
+use async_trait::async_trait;
+use goose::conversation::message::{Message, ToolRequest};
+use goose::tool_inspection::{
+    InspectionAction, InspectionResult, ToolInspectionManager, ToolInspector,
+};
+
+struct MockInspectorOk {
+    name: &'static str,
+    results: Vec<InspectionResult>,
+}
+
+struct MockInspectorErr {
+    name: &'static str,
+}
+
+#[async_trait]
+impl ToolInspector for MockInspectorOk {
+    fn name(&self) -> &'static str {
+        self.name
+    }
+    fn as_any(&self) -> &dyn std::any::Any {
+        self
+    }
+    async fn inspect(
+        &self,
+        _tool_requests: &[ToolRequest],
+        _messages: &[Message],
+    ) -> Result<Vec<InspectionResult>> {
+        Ok(self.results.clone())
+    }
+}
+
+#[async_trait]
+impl ToolInspector for MockInspectorErr {
+    fn name(&self) -> &'static str {
+        self.name
+    }
+    fn as_any(&self) -> &dyn std::any::Any {
+        self
+    }
+    async fn inspect(
+        &self,
+        _tool_requests: &[ToolRequest],
+        _messages: &[Message],
+    ) -> Result<Vec<InspectionResult>> {
+        Err(anyhow!("simulated failure"))
+    }
+}
+
+#[tokio::test]
+async fn test_inspect_tools_aggregates_and_handles_errors() {
+    // Arrange: create a manager with one successful and one failing inspector
+    let ok_results = vec![
+        InspectionResult {
+            tool_request_id: "req_1".to_string(),
+            action: InspectionAction::Allow,
+            reason: "looks safe".to_string(),
+            confidence: 0.95,
+            inspector_name: "ok".to_string(),
+            finding_id: None,
+        },
+        InspectionResult {
+            tool_request_id: "req_2".to_string(),
+            action: InspectionAction::RequireApproval(Some("double check".to_string())),
+            reason: "needs user confirmation".to_string(),
+            confidence: 0.7,
+            inspector_name: "ok".to_string(),
+            finding_id: Some("FND-123".to_string()),
+        },
+    ];
+
+    let mut manager = ToolInspectionManager::new();
+    manager.add_inspector(Box::new(MockInspectorOk {
+        name: "ok",
+        results: ok_results.clone(),
+    }));
+    manager.add_inspector(Box::new(MockInspectorErr { name: "err" }));
+
+    // No specific input is required for this aggregation behavior
+    let tool_requests: Vec<ToolRequest> = vec![];
+    let messages: Vec<Message> = vec![];
+
+    // Act
+    let results = manager
+        .inspect_tools(&tool_requests, &messages)
+        .await
+        .expect("inspect_tools should not fail when one inspector errors");
+
+    // Assert: results from the successful inspector are returned; failing inspector is ignored
+    assert_eq!(
+        results.len(),
+        2,
+        "Should aggregate results from successful inspectors only"
+    );
+    // Also verify inspector_names() order/presence
+    let names = manager.inspector_names();
+    assert_eq!(
+        names,
+        vec!["ok", "err"],
+        "Inspector names should reflect registration order"
+    );
+
+    // Verify that specific actions are preserved
+    assert!(results
+        .iter()
+        .any(|r| matches!(r.action, InspectionAction::Allow)));
+    assert!(results
+        .iter()
+        .any(|r| matches!(r.action, InspectionAction::RequireApproval(_))));
+}