Support .asciidoctorconfig at root of the workspace

part of asciidoctor#380

TODO in this PR:
- provide test

TODO in other iteration:
- support other places
- support `.asciidoctorconfig.adoc`
- provide cache mechanism

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## Unreleased
 
+### Improvements
+
+- support .asciidoctorconfig at root of the workspace by @apupier (#380)
+
 ### Bug fixes
 
 - fix the logic that detects if `asciidoctor-pdf` and/or `bundler` are available in the `PATH`

README.md

@@ -166,6 +166,14 @@ Here's an example of how to use the [asciidoctor-emoji](https://github.com/mogzt
 
 ![Asciidoctor.js Emoji extension enabled!](images/asciidoctor-vscode-emoji-ext.png)
 
+### Asciidoctor Config File
+
+To provide a common set of variables when rendering the preview, the extension reads an `.asciidoctorconfig` configuration file. Use this to optimize the preview when the project contains a document that is split out to multiple include-files.
+
+It is inspired by the implementation provided in [IntelliJ AsciiDoc Plugin](https://intellij-asciidoc-plugin.ahus1.de/docs/users-guide/features/advanced/asciidoctorconfig-file.html) and reused in [Eclipse AsciiDoc plugin](https://github.com/de-jcup/eclipse-asciidoctor-editor/wiki/Asciidoctor-configfiles).
+
+The current scope is limited to an `.asciidoctorconfig` configuration file provided at the root of the workspace.
+
 ## Extension Settings
 
 This extension contributes the following settings:

src/asciidocParser.ts

@@ -1,4 +1,5 @@
 import * as vscode from 'vscode'
+import * as fs from 'fs'
 import * as path from 'path'
 import { AsciidoctorWebViewConverter } from './asciidoctorWebViewConverter'
 import { Asciidoctor } from '@asciidoctor/core'
@@ -172,6 +173,17 @@ export class AsciidocParser {
     }
 
     try {
+      const workspaceFolder = vscode.workspace.getWorkspaceFolder(doc.uri)
+      if (workspaceFolder !== undefined) {
+        const asciiDoctorConfig = vscode.Uri.joinPath(workspaceFolder.uri, '.asciidoctorconfig')
+        if (fs.existsSync(asciiDoctorConfig.fsPath)) {
+          const asciiDoctorConfigContent = await vscode.workspace.fs.readFile(asciiDoctorConfig)
+          text =
+            ':asciidoctorconfigdir: ' + asciiDoctorConfig.fsPath + '\n\n' +
+            asciiDoctorConfigContent + '\n\n' +
+            text
+        }
+      }
       const document = processor.load(text, options)
       const blocksWithLineNumber = document.findBy(function (b) {
         return typeof b.getLineNumber() !== 'undefined'