pubspec.yaml: A dependency may only have one source.

発生したエラー

• pubspec.yamlにカスタムフォントをセットした後にflutter runを試したところ、下記のエラーが発生した。

Error on line 32, column 5 of pubspec.yaml: A dependency may only have one source.
   ╷
32 │ ┌     sdk: flutter
33 │ │     fonts:
34 │ │     - family: NotoSansJP
35 │ │       fonts:
36 │ │         - asset: static/fonts/NotoSansJP-Regular.ttf
37 │ │
38 │ │   # The following adds the Cupertino Icons font to your application.
39 │ │   # Use with the CupertinoIcons class for iOS style icons.
40 │ │   cupertino_icons: ^1.0.8
   │ └──^
   ╵

解決策

• flutter: の場所が違った。

誤.yaml

dependencies:
  flutter:
    sdk: flutter
    ＃NG

  # The following adds the Cupertino Icons font to your application.
  # Use with the CupertinoIcons class for iOS style icons.
  cupertino_icons: ^1.0.8
  rename_app: ^1.6.5
  change_app_package_name: ^1.5.0

正.yaml

flutter:
  ＃✅OK
  fonts:
  - family: NotoSansJP
    fonts:
      - asset: static/fonts/NotoSansJP-Regular.ttf

  # The following line ensures that the Material Icons font is
  # included with your application, so that you can use the icons in
  # the material Icons class.