1 files changed, 17 insertions, 2 deletions
diff --git a/node_modules/@babel/helper-create-class-features-plugin/lib/features.js b/node_modules/@babel/helper-create-class-features-plugin/lib/features.js
index a4ad9ff8..5cc919c6 100644
--- a/node_modules/@babel/helper-create-class-features-plugin/lib/features.js
+++ b/node_modules/@babel/helper-create-class-features-plugin/lib/features.js
@@ -47,7 +47,7 @@ function enableFeature(file, feature, loose) {
     }
     const loose = isLoose(file, mask);
     if (resolvedLoose === !loose) {
-      throw new Error("'loose' mode configuration must be the same for @babel/plugin-transform-class-properties, " + "@babel/plugin-transform-private-methods and " + "@babel/plugin-transform-private-property-in-object (when they are enabled).");
+      throw new Error("'loose' mode configuration must be the same for @babel/plugin-transform-class-properties, " + "@babel/plugin-transform-private-methods and " + "@babel/plugin-transform-private-property-in-object (when they are enabled)." + "\n\n" + getBabelShowConfigForHint(file));
     } else {
       resolvedLoose = loose;
       {
@@ -59,11 +59,26 @@ function enableFeature(file, feature, loose) {
     for (const [mask, name] of featuresSameLoose) {
       if (hasFeature(file, mask) && isLoose(file, mask) !== resolvedLoose) {
         setLoose(file, mask, resolvedLoose);
-        console.warn(`Though the "loose" option was set to "${!resolvedLoose}" in your @babel/preset-env ` + `config, it will not be used for ${name} since the "loose" mode option was set to ` + `"${resolvedLoose}" for ${higherPriorityPluginName}.\nThe "loose" option must be the ` + `same for @babel/plugin-transform-class-properties, @babel/plugin-transform-private-methods ` + `and @babel/plugin-transform-private-property-in-object (when they are enabled): you can ` + `silence this warning by explicitly adding\n` + `\t["${name}", { "loose": ${resolvedLoose} }]\n` + `to the "plugins" section of your Babel config.`);
+        console.warn(`Though the "loose" option was set to "${!resolvedLoose}" in your @babel/preset-env ` + `config, it will not be used for ${name} since the "loose" mode option was set to ` + `"${resolvedLoose}" for ${higherPriorityPluginName}.\nThe "loose" option must be the ` + `same for @babel/plugin-transform-class-properties, @babel/plugin-transform-private-methods ` + `and @babel/plugin-transform-private-property-in-object (when they are enabled): you can ` + `silence this warning by explicitly adding\n` + `\t["${name}", { "loose": ${resolvedLoose} }]\n` + `to the "plugins" section of your Babel config.` + "\n\n" + getBabelShowConfigForHint(file));
       }
     }
   }
 }
+function getBabelShowConfigForHint(file) {
+  let {
+    filename
+  } = file.opts;
+  if (!filename || filename === "unknown") {
+    filename = "[name of the input file]";
+  }
+  return `\
+If you already set the same 'loose' mode for these plugins in your config, it's possible that they \
+are enabled multiple times with different options.
+You can re-run Babel with the BABEL_SHOW_CONFIG_FOR environment variable to show the loaded \
+configuration:
+\tnpx cross-env BABEL_SHOW_CONFIG_FOR=${filename} <your build command>
+See https://babeljs.io/docs/configuration#print-effective-configs for more info.`;
+}
 function hasFeature(file, feature) {
   return !!(file.get(featuresKey) & feature);
 }