From ffc6a72045ce7754992ba33ccd4339afcb1fc47e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Hua=CC=81ng=20Ju=CC=80nlia=CC=80ng?= <i@jhuang.me>
Date: Tue, 9 Jul 2019 19:04:45 -0400
Subject: [PATCH] docs: rewrite validate error message

per https://github.com/babel/babel/pull/10181#discussion_r301607986
---
 packages/babel-core/src/config/full.js   | 13 +++++++++++--
 packages/babel-core/test/config-chain.js |  4 ++--
 2 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/packages/babel-core/src/config/full.js b/packages/babel-core/src/config/full.js
index eba908c2566e..5ba198d91d17 100644
--- a/packages/babel-core/src/config/full.js
+++ b/packages/babel-core/src/config/full.js
@@ -284,9 +284,18 @@ const validateIfOptionNeedsFilename = (
   descriptor: UnloadedDescriptor,
 ): void => {
   if (options.test || options.include || options.exclude) {
+    const formattedPresetName = descriptor.name
+      ? `"${descriptor.name}"`
+      : "/* your preset */";
     throw new Error(
-      `Preset ${descriptor.name ||
-        ""} requires filename, but it was not passed.`.replace(/\s{2}/, " "),
+      [
+        `Preset ${formattedPresetName} requires a filename be set.`,
+        `For example, if you are calling Babel directly`,
+        `\`\`\``,
+        `babel.transform(code, { filename: 'file.js', presets: [${formattedPresetName}] });`,
+        `\`\`\``,
+        `See https://babeljs.io/docs/en/options#filename for more information.`,
+      ].join("\n"),
     );
   }
 };
diff --git a/packages/babel-core/test/config-chain.js b/packages/babel-core/test/config-chain.js
index 7aacbe62d1e9..f1f67d430327 100644
--- a/packages/babel-core/test/config-chain.js
+++ b/packages/babel-core/test/config-chain.js
@@ -1061,7 +1061,7 @@ describe("buildConfigChain", function() {
         loadOptions({
           presets: [require("./fixtures/config-loading/preset4")],
         });
-      }).toThrow(/Preset requires filename/);
+      }).toThrow(/Preset \/\* your preset \*\/ requires sa filename/);
     });
 
     it("should throw when `preset.overrides` requires `filename` but it was not passed", () => {
@@ -1069,7 +1069,7 @@ describe("buildConfigChain", function() {
         loadOptions({
           presets: [require("./fixtures/config-loading/preset5")],
         });
-      }).toThrow(/Preset requires filename/);
+      }).toThrow(/Preset \/\* your preset \*\/ requires a filename/);
     });
   });
 });