Patch facebook/metro#1130 to profile module init (#1796)

1 files changed, 44 insertions, 0 deletions

diff --git a/patches/metro+0.76.8.patch b/patches/metro+0.76.8.patch
new file mode 100644
index 000000000..f8ef67c84
--- /dev/null
+++ b/patches/metro+0.76.8.patch
@@ -0,0 +1,44 @@
+diff --git a/node_modules/metro/src/ModuleGraph/worker/JsFileWrapping.js b/node_modules/metro/src/ModuleGraph/worker/JsFileWrapping.js
+index 48a1409..ef185c9 100644
+--- a/node_modules/metro/src/ModuleGraph/worker/JsFileWrapping.js
++++ b/node_modules/metro/src/ModuleGraph/worker/JsFileWrapping.js
+@@ -70,14 +70,19 @@ function wrapModule(
+   importDefaultName,
+   importAllName,
+   dependencyMapName,
+-  globalPrefix
++  globalPrefix,
++  moduleFactoryName
+ ) {
+   const params = buildParameters(
+     importDefaultName,
+     importAllName,
+     dependencyMapName
+   );
+-  const factory = functionFromProgram(fileAst.program, params);
++  const factory = functionFromProgram(
++    fileAst.program,
++    params,
++    moduleFactoryName
++  );
+   const def = t.callExpression(t.identifier(`${globalPrefix}__d`), [factory]);
+   const ast = t.file(t.program([t.expressionStatement(def)]));
+   const requireName = renameRequires(ast);
+@@ -107,7 +112,16 @@ function wrapJson(source, globalPrefix) {
+     "});",
+   ].join("\n");
+ }
+-function functionFromProgram(program, parameters) {
++const JS_INVALID_IDENT_RE = /[^a-zA-Z0-9$_]/g;
++function functionFromProgram(program, parameters, moduleFactoryName) {
++  let identifier;
++  if (typeof moduleFactoryName === "string" && moduleFactoryName !== "") {
++    // Keep the name readable so it shows up in profiler traces.
++    // Add an unlikely suffix to avoid collisions with the module code.
++    identifier = t.identifier(
++      `${moduleFactoryName.replace(JS_INVALID_IDENT_RE, "_")}__module_factory__`
++    );
++  }
+   return t.functionExpression(
+     undefined,
+     parameters.map(makeIdentifier),