fix: clipboard.read() to recognize custom types (#31623)

docs/api/clipboard.md

@@ -197,7 +197,7 @@ Returns `Boolean` - Whether the clipboard supports the specified `format`.
 ```js
 const { clipboard } = require('electron')
 
-const hasFormat = clipboard.has('<p>selection</p>')
+const hasFormat = clipboard.has('public/utf8-plain-text')
 console.log(hasFormat)
 // 'true' or 'false'
 ```

shell/common/api/electron_api_clipboard.cc

@@ -51,17 +51,7 @@ bool Clipboard::Has(const std::string& format_string,
 
 std::string Clipboard::Read(const std::string& format_string) {
   ui::Clipboard* clipboard = ui::Clipboard::GetForCurrentThread();
-  ui::ClipboardFormatType format(
-      ui::ClipboardFormatType::CustomPlatformType(format_string));
-
-  std::string data;
-  clipboard->ReadData(format, /* data_dst = */ nullptr, &data);
-  return data;
-}
 
-v8::Local<v8::Value> Clipboard::ReadBuffer(const std::string& format_string,
-                                           gin_helper::Arguments* args) {
-  ui::Clipboard* clipboard = ui::Clipboard::GetForCurrentThread();
   std::map<std::string, std::string> custom_format_names;
   custom_format_names =
       clipboard->ExtractCustomPlatformNames(ui::ClipboardBuffer::kCopyPaste,
@@ -73,12 +63,24 @@ v8::Local<v8::Value> Clipboard::ReadBuffer(const std::string& format_string,
                                               /* data_dst = */ nullptr);
   }
 #endif
-  CHECK(custom_format_names.find(format_string) != custom_format_names.end());
-  ui::ClipboardFormatType format(ui::ClipboardFormatType::CustomPlatformType(
-      custom_format_names[format_string]));
 
+  ui::ClipboardFormatType format;
+  if (custom_format_names.find(format_string) != custom_format_names.end()) {
+    format =
+        ui::ClipboardFormatType(ui::ClipboardFormatType::CustomPlatformType(
+            custom_format_names[format_string]));
+  } else {
+    format = ui::ClipboardFormatType(
+        ui::ClipboardFormatType::CustomPlatformType(format_string));
+  }
   std::string data;
   clipboard->ReadData(format, /* data_dst = */ nullptr, &data);
+  return data;
+}
+
+v8::Local<v8::Value> Clipboard::ReadBuffer(const std::string& format_string,
+                                           gin_helper::Arguments* args) {
+  std::string data = Read(format_string);
   return node::Buffer::Copy(args->isolate(), data.data(), data.length())
       .ToLocalChecked();
 }

spec/api-clipboard-spec.js

@@ -1,7 +1,7 @@
 const { expect } = require('chai');
 const path = require('path');
 const { Buffer } = require('buffer');
-const { ifdescribe } = require('./spec-helpers');
+const { ifdescribe, ifit } = require('./spec-helpers');
 
 const { clipboard, nativeImage } = require('electron');
 
@@ -62,14 +62,20 @@ ifdescribe(process.platform !== 'win32' || process.arch !== 'arm64')('clipboard
     });
   });
 
-  ifdescribe(process.platform !== 'linux')('clipboard.read()', () => {
-    it('does not crash when reading various custom clipboard types', () => {
+  describe('clipboard.read()', () => {
+    ifit(process.platform !== 'linux')('does not crash when reading various custom clipboard types', () => {
       const type = process.platform === 'darwin' ? 'NSFilenamesPboardType' : 'FileNameW';
 
       expect(() => {
         const result = clipboard.read(type);
       }).to.not.throw();
     });
+    it('can read data written with writeBuffer', () => {
+      const testText = 'Testing read';
+      const buffer = Buffer.from(testText, 'utf8');
+      clipboard.writeBuffer('public/utf8-plain-text', buffer);
+      expect(clipboard.read('public/utf8-plain-text')).to.equal(testText);
+    });
   });
 
   describe('clipboard.write()', () => {