From 7737c4076358fe7da7d9a19ec9a40bfcdf794e15 Mon Sep 17 00:00:00 2001
From: Tim Fish <tim@timfish.uk>
Date: Tue, 26 May 2026 12:43:31 +0100
Subject: [PATCH 1/4] feat: Expose Transformer `moduleName`

---
 lib/transformer.js | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/lib/transformer.js b/lib/transformer.js
index 990686b..399d079 100644
--- a/lib/transformer.js
+++ b/lib/transformer.js
@@ -41,6 +41,11 @@ class Transformer {
   /** No-op — freeing resources is not needed for the JavaScript implementation. */
   free () {}
 
+  /** The npm package name being instrumented. */
+  get moduleName () {
+    return this.#moduleName
+  }
+
   /**
    * Instruments `code` by injecting diagnostics_channel tracing around the
    * target functions defined by this transformer's configs.

From 61ed7ce8916a60ffb915bdccbb807221b71da5df Mon Sep 17 00:00:00 2001
From: Tim Fish <tim@timfish.uk>
Date: Tue, 26 May 2026 13:34:05 +0100
Subject: [PATCH 2/4] Types!

---
 index.d.ts | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index eee2794..d0d0f26 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -104,6 +104,12 @@ export class InstrumentationMatcher {
 export class Transformer {
   private constructor();
   free(): void;
+
+  /**
+   * The name of the module to transform.
+   */
+  get moduleName(): string;
+
   /**
    * Transform JavaScript code and optionally sourcemap.
    *

From 1c048fbb519814b7093a9ad376b5473fc3952e8a Mon Sep 17 00:00:00 2001
From: Tim Fish <tim@timfish.uk>
Date: Tue, 26 May 2026 13:46:40 +0100
Subject: [PATCH 3/4] PR review

Co-authored-by: James Sumners <jsumners@newrelic.com>
---
 lib/transformer.js | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/lib/transformer.js b/lib/transformer.js
index 399d079..534e2f0 100644
--- a/lib/transformer.js
+++ b/lib/transformer.js
@@ -41,7 +41,11 @@ class Transformer {
   /** No-op — freeing resources is not needed for the JavaScript implementation. */
   free () {}
 
-  /** The npm package name being instrumented. */
+  /**
+   * The npm package name being instrumented.
+   *
+   * @returns {string}
+   */
   get moduleName () {
     return this.#moduleName
   }

From 5e18a322bbbca5a49fc5b17e60ac8146bae39e5d Mon Sep 17 00:00:00 2001
From: Tim Fish <tim@timfish.uk>
Date: Tue, 26 May 2026 13:50:33 +0100
Subject: [PATCH 4/4] Add `filePath` too

---
 index.d.ts         | 7 +++++++
 lib/transformer.js | 9 +++++++++
 2 files changed, 16 insertions(+)

diff --git a/index.d.ts b/index.d.ts
index d0d0f26..7d2ec98 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -110,6 +110,13 @@ export class Transformer {
    */
   get moduleName(): string;
 
+  /**
+   * The relative file path within the npm package being instrumented.
+   *
+   * @returns {string}
+   */
+  get filePath(): string;
+
   /**
    * Transform JavaScript code and optionally sourcemap.
    *
diff --git a/lib/transformer.js b/lib/transformer.js
index 534e2f0..663e3cb 100644
--- a/lib/transformer.js
+++ b/lib/transformer.js
@@ -50,6 +50,15 @@ class Transformer {
     return this.#moduleName
   }
 
+  /**
+   * The relative file path within the npm package being instrumented.
+   *
+   * @returns {string}
+   */
+  get filePath () {
+    return this.#filePath
+  }
+
   /**
    * Instruments `code` by injecting diagnostics_channel tracing around the
    * target functions defined by this transformer's configs.