Fix the same channel name being used multiple times for instrumented methods in the same module or script

src/instrumentation.rs

@@ -186,15 +186,19 @@ impl Instrumentation {
     // `visit_mut_children_with`.
 
     pub fn visit_mut_module(&mut self, node: &mut Module) -> bool {
-        node.body
-            .insert(1, ModuleItem::Stmt(self.create_tracing_channel()));
+        let channel_element = ModuleItem::Stmt(self.create_tracing_channel());
+        if !node.body.iter().any(|item| item == &channel_element) {
+            node.body.insert(1, channel_element);
+        }
         true
     }
 
     pub fn visit_mut_script(&mut self, node: &mut Script) -> bool {
         let start_index = get_script_start_index(node);
-        node.body
-            .insert(start_index + 1, self.create_tracing_channel());
+        let channel_element = self.create_tracing_channel();
+        if !node.body.iter().any(|item| item == &channel_element) {
+            node.body.insert(start_index + 1, channel_element);
+        }
         true
     }
 

tests/instrumentor_test.rs

@@ -17,3 +17,5 @@ mod multiple_load_cjs;
 mod object_method_cjs;
 mod polyfill_cjs;
 mod polyfill_mjs;
+mod single_channel_multiple_usages_cjs;
+mod single_channel_multiple_usages_mjs;

tests/single_channel_multiple_usages_cjs/mod.js

@@ -0,0 +1,9 @@
+async function foo () {
+  return 'foo'
+}
+
+async function bar () {
+  return 'bar'
+}
+
+module.exports = { foo, bar };

tests/single_channel_multiple_usages_cjs/mod.rs

@@ -0,0 +1,25 @@
+use crate::common::*;
+use orchestrion_js::*;
+
+#[test]
+fn same_channel_multiple_usages_cjs() {
+    transpile_and_test(
+        file!(),
+        false,
+        Config::new(
+            vec![
+                InstrumentationConfig::new(
+                    "method_call",
+                    test_module_matcher(),
+                    FunctionQuery::function_declaration("foo", FunctionKind::Async),
+                ),
+                InstrumentationConfig::new(
+                    "method_call",
+                    test_module_matcher(),
+                    FunctionQuery::function_declaration("bar", FunctionKind::Async),
+                ),
+            ],
+            None,
+        ),
+    );
+}

tests/single_channel_multiple_usages_cjs/test.js

@@ -0,0 +1,26 @@
+/**
+ * Unless explicitly stated otherwise all files in this repository are licensed under the Apache-2.0 License.
+ * This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2025 Datadog, Inc.
+ **/
+const { foo, bar } = require('./instrumented.js');
+const { assert, getContext } = require('../common/preamble.js');
+const context = getContext('orchestrion:undici:method_call');
+(async () => {
+  const result = await foo();
+  assert.strictEqual(result, 'foo');
+  assert.deepStrictEqual(context, {
+    start: true,
+    end: true,
+    asyncStart: 'foo',
+    asyncEnd: 'foo'
+  });
+
+  const result2 = await bar();
+  assert.strictEqual(result2, 'bar');
+  assert.deepStrictEqual(context, {
+    start: true,
+    end: true,
+    asyncStart: 'bar',
+    asyncEnd: 'bar'
+  });
+})();

tests/single_channel_multiple_usages_mjs/mod.mjs

@@ -0,0 +1,9 @@
+async function foo () {
+  return 'foo'
+}
+
+async function bar () {
+  return 'bar'
+}
+
+export { foo, bar };

tests/single_channel_multiple_usages_mjs/mod.rs

@@ -0,0 +1,25 @@
+use crate::common::*;
+use orchestrion_js::*;
+
+#[test]
+fn same_channel_multiple_usages_mjs() {
+    transpile_and_test(
+        file!(),
+        true,
+        Config::new(
+            vec![
+                InstrumentationConfig::new(
+                    "method_call",
+                    test_module_matcher(),
+                    FunctionQuery::function_declaration("foo", FunctionKind::Async),
+                ),
+                InstrumentationConfig::new(
+                    "method_call",
+                    test_module_matcher(),
+                    FunctionQuery::function_declaration("bar", FunctionKind::Async),
+                ),
+            ],
+            None,
+        ),
+    );
+}

tests/single_channel_multiple_usages_mjs/test.mjs

@@ -0,0 +1,24 @@
+/**
+ * Unless explicitly stated otherwise all files in this repository are licensed under the Apache-2.0 License.
+ * This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2025 Datadog, Inc.
+ **/
+import { foo, bar } from './instrumented.mjs';
+import { assert, getContext } from '../common/preamble.js';
+const context = getContext('orchestrion:undici:method_call');
+const result = await foo();
+assert.strictEqual(result, 'foo');
+assert.deepStrictEqual(context, {
+  start: true,
+  end: true,
+  asyncStart: 'foo',
+  asyncEnd: 'foo'
+});
+
+const result2 = await bar();
+assert.strictEqual(result2, 'bar');
+assert.deepStrictEqual(context, {
+  start: true,
+  end: true,
+  asyncStart: 'bar',
+  asyncEnd: 'bar'
+});