Can I open a binary file as a text document?

[racz16]

I have .spv files that contain statements from a binary intermediate language called SPIR-V (you can think about it like IL code, or Java bytecode). Can I create an extension that opens a read-only text editor with language features, that contains the assembly-like text representation of the statements when I open those files? Since these are generated files, I don't ever want to edit them.

I can't use the regular language features, the custom text editor, or the Language Server Protocol directly on the .spv files, since they are binary. I have some workarounds, but they are not perfect. I could create a command that either generates and opens a text-based file on disk or opens a virtual document. However, this means that the user has to manually trigger this after she/he opens the binary document. I could create a custom editor and show the assembly in the webview, but I'd lose all language features, like syntax highlight, go to definition, etc. I could create an empty custom editor, and when it's opened, I also open a virtual document, and close the custom editor. However, this is a hack, and also, the custom editor is still showing up.

Is there a valid way to open a binary file as a text document?

[tamuratak]

You can refer to vscode-extension-samples/custom-editor-sample. It includes:

Paw Draw - Uses the binary custom editor api to provide a custom editor for .pawdraw files (which are just png files with a different file extension).

[racz16]

I saw the custom editor sample, but it's not what I need. The sample opens a binary file and shows its content as an image in a webview.

I have a binary file too, but I don't want to show it to the user in a webview. Instead, I'd like to parse the file, and show the text representation of it in a text editor. The result would look something like this:

     OpCapability Shader
     OpMemoryModel Logical GLSL450
     OpEntryPoint Vertex %3 "main"
%1 = OpTypeVoid
%2 = OpTypeFunction %1
%3 = OpFunction %1 None %2
%4 = OpLabel
     OpReturn
     OpFunctionEnd

Then I could use VS Code's language features, like syntax highlighting, go to definition, code completion, etc.

[alefragnani]

Hi @racz16 ,

Right now, your scenario is not supported. Both Custom Editors API (CustomTextEditorProvider and CustomEditorProvider) are intended for read/write editors, which means they intend to give the extension author a custom view to display/edit the file. That's why both APIs require the extension to provide a WebView as the container of its file.

You could use Monaco Editor or ShikiJS in order to have syntax highlighting capabilities, but language features like Got To Definition or Code Completion won't be available out of the box.

If this doesn't fit your needs, I would suggest you to open a feature request in the VS Code repo (https://github.com/microsoft/vscode/issues) so the VS Code team could take a look.

Hope this helps

[racz16]

I hoped that there is something similar to TextDocumentContentProvider where I can provide the content of a text document based on a binary file, but as the main view of the file, not as a separate view. But thank you, you answered my question.