make comment-based replacement blocks with legal comment syntax

mydea · mydea · commit 8dc63cf93e6e · 2026-05-13T16:21:39.000+02:00
diff --git a/dev-packages/rollup-utils/plugins/bundlePlugins.mjs b/dev-packages/rollup-utils/plugins/bundlePlugins.mjs
@@ -63,18 +63,19 @@ export function makeIsDebugBuildPlugin(includeDebugging) {
 }
 
 /**
- * Replaces the comment marker `/* __SENTRY_SDK_SOURCE__ *\/` in core's `getSDKSource()` with a
+ * Replaces the comment marker `/*! __SENTRY_SDK_SOURCE__ *\/` in core's `getSDKSource()` with a
  * `return '<source>';` statement so the bundle reports the correct distribution channel.
  *
- * Because the marker is a block comment, esbuild would strip it during transpile — so the plugin
- * sort order in utils.mjs pins this name before `esbuild`.
+ * The marker uses the `/*! ... *\/` legal-comment syntax so it survives esbuild's transpile
+ * (esbuild strips ordinary block comments). The plugin sort order in utils.mjs also pins
+ * this name before `esbuild`, in case it ever runs on un-transpiled source directly.
  */
 export function makeSetSDKSourcePlugin(sdkSource) {
   const plugin = replace({
     preventAssignment: false,
     delimiters: ['', ''],
     values: {
-      '/* __SENTRY_SDK_SOURCE__ */': `return ${JSON.stringify(sdkSource)};`,
+      '/*! __SENTRY_SDK_SOURCE__ */': `return ${JSON.stringify(sdkSource)};`,
     },
   });
   plugin.name = 'replace-sdk-source';
diff --git a/dev-packages/rollup-utils/plugins/npmPlugins.mjs b/dev-packages/rollup-utils/plugins/npmPlugins.mjs
@@ -121,12 +121,14 @@ export function makeDebugBuildStatementReplacePlugin() {
 }
 
 export function makeProductionReplacePlugin() {
-  const pattern = /\/\* rollup-include-development-only \*\/[\s\S]*?\/\* rollup-include-development-only-end \*\/\s*/g;
-
-  // Must run as a `transform` (per-module) hook rather than `renderChunk`: esbuild
-  // strips arbitrary block comments during transpile, so by the time `renderChunk`
-  // would fire, the `rollup-include-development-only` marker comments are gone.
+  // Markers use the `/*! ... */` legal-comment syntax so esbuild preserves them through
+  // transpile. We still run as a `transform` (per-module) hook rather than `renderChunk`:
+  // the block typically uses imports declared at the module top, and stripping it before
+  // rollup analyses module-graph imports lets those now-unused imports be tree-shaken away.
   // The plugin sort order in utils.mjs pins this before `esbuild`.
+  const pattern =
+    /\/\*! rollup-include-development-only \*\/[\s\S]*?\/\*! rollup-include-development-only-end \*\/\s*/g;
+
   return {
     name: 'remove-dev-mode-blocks',
     transform(code) {
diff --git a/packages/browser/src/sdk.ts b/packages/browser/src/sdk.ts
@@ -98,15 +98,15 @@ export function init(options: BrowserOptions = {}): Client | undefined {
   let defaultIntegrations =
     options.defaultIntegrations == null ? getDefaultIntegrations(options) : options.defaultIntegrations;
 
-  /* rollup-include-development-only */
+  /*! rollup-include-development-only */
   if (options.spotlight) {
     if (!defaultIntegrations) {
       defaultIntegrations = [];
     }
     const args = typeof options.spotlight === 'string' ? { sidecarUrl: options.spotlight } : undefined;
     defaultIntegrations.push(spotlightBrowserIntegration(args));
   }
-  /* rollup-include-development-only-end */
+  /*! rollup-include-development-only-end */
 
   const clientOptions: BrowserClientOptions = {
     ...options,
diff --git a/packages/core/src/utils/env.ts b/packages/core/src/utils/env.ts
@@ -30,6 +30,8 @@ export function isBrowserBundle(): boolean {
  * Get source of SDK.
  */
 export function getSDKSource(): SdkSource {
-  // This comment is used to identify this line in the CDN bundle build step and replace this with "return 'cdn';"
-  /* __SENTRY_SDK_SOURCE__ */ return 'npm';
+  // The `/*! ... */` marker is replaced by our CDN bundle build step with `return 'cdn';`.
+  // It uses the `/*!` legal-comment syntax specifically so it survives esbuild's transpile
+  // (which strips ordinary `/* ... */` block comments).
+  /*! __SENTRY_SDK_SOURCE__ */ return 'npm';
 }
