module: print amount of load time of a module

Author: H4ad

lib/internal/modules/cjs/loader.js

@@ -970,6 +970,8 @@ function getExportsForCircularRequire(module) {
  * @param {boolean} isMain Whether the module is the main entry point
  */
 Module._load = function(request, parent, isMain) {
+  const start = performance.now();
+
   let relResolveCacheIdentifier;
   if (parent) {
     debug('Module._load REQUEST %s parent: %s', request, parent.id);
@@ -984,8 +986,14 @@ Module._load = function(request, parent, isMain) {
       if (cachedModule !== undefined) {
         updateChildren(parent, cachedModule, true);
         if (!cachedModule.loaded) {
-          return getExportsForCircularRequire(cachedModule);
+          const result = getExportsForCircularRequire(cachedModule);
+
+          debug(`TIMING [%s]: %d ms`, request, performance.now() - start);
+
+          return result;
         }
+
+        debug(`TIMING [%s]: %d ms`, request, performance.now() - start);
         return cachedModule.exports;
       }
       delete relativeResolveCache[relResolveCacheIdentifier];
@@ -1001,6 +1009,8 @@ Module._load = function(request, parent, isMain) {
     }
 
     const module = loadBuiltinModule(id, request);
+
+    debug(`TIMING [%s]: %d ms`, request, performance.now() - start);
     return module.exports;
   }
 
@@ -1011,16 +1021,24 @@ Module._load = function(request, parent, isMain) {
     if (!cachedModule.loaded) {
       const parseCachedModule = cjsSourceCache.get(cachedModule);
       if (!parseCachedModule || parseCachedModule.loaded) {
-        return getExportsForCircularRequire(cachedModule);
+        const result = getExportsForCircularRequire(cachedModule);
+
+        debug(`TIMING [%s]: %d ms`, request, performance.now() - start);
+
+        return result;
       }
       parseCachedModule.loaded = true;
     } else {
+      debug(`TIMING [%s]: %d ms`, request, performance.now() - start);
       return cachedModule.exports;
     }
   }
 
   if (BuiltinModule.canBeRequiredWithoutScheme(filename)) {
     const mod = loadBuiltinModule(filename, request);
+
+    debug(`TIMING [%s]: %d ms`, request, performance.now() - start);
+
     return mod.exports;
   }
 
@@ -1068,6 +1086,8 @@ Module._load = function(request, parent, isMain) {
     }
   }
 
+  debug(`TIMING [%s]: %d ms`, request, performance.now() - start);
+
   return module.exports;
 };