add new outline from headings

src/extension.ts

@@ -8,6 +8,7 @@ import {ActionProvider} from './actionProvider';
 import {Completer} from './completer';
 import {Formatter} from './formatter';
 import {runCmd} from './utils';
+import {SymbolProvider} from './symbolProvider';
 
 export function activate(context: vscode.ExtensionContext) {
   const extension = new Extension(context);
@@ -79,6 +80,13 @@ export function activate(context: vscode.ExtensionContext) {
   if (vscode.workspace.getConfiguration('beancount')['runFavaOnActivate']) {
     extension.favaManager.openFava(false);
   }
+
+  context.subscriptions.push(
+      vscode.languages.registerDocumentSymbolProvider(
+          {scheme: 'file', language: 'beancount'},
+          extension.symbolProvider,
+      ),
+  );
 }
 
 export function deactivate() { }
@@ -92,6 +100,7 @@ export class Extension {
   logger: vscode.OutputChannel;
   flagWarnings: FlagWarnings;
   context: vscode.ExtensionContext;
+  symbolProvider: SymbolProvider;
 
   constructor(context: vscode.ExtensionContext) {
     this.context = context;
@@ -106,6 +115,7 @@ export class Extension {
     this.flagWarnings = vscode.workspace.getConfiguration('beancount')[
         'flagWarnings'
     ];
+    this.symbolProvider = new SymbolProvider();
   }
 
   resolveToAbsolutePath(path: string) {

src/symbolProvider.ts

@@ -0,0 +1,124 @@
+import * as vscode from 'vscode';
+
+interface BlockData {
+  name: string,
+  level: number,
+  kind: vscode.SymbolKind,
+  start: vscode.TextLine,
+  end: vscode.TextLine,
+}
+
+class LevelDocumentSymbol extends vscode.DocumentSymbol {
+  level: number;
+
+  constructor(name: string, detail: string, kind: vscode.SymbolKind,
+      range: vscode.Range, selectionRange: vscode.Range, level: number) {
+    super(name, detail, kind, range, selectionRange);
+    this.level = level;
+  }
+}
+
+export class SymbolProvider implements vscode.DocumentSymbolProvider {
+  private parseText(text: string): BlockData {
+    const data: BlockData = {
+      name: '',
+      level: 0,
+      kind: vscode.SymbolKind.Class,
+      start: {} as vscode.TextLine,
+      end: {} as vscode.TextLine,
+    };
+    for (let i = 0; i < text.length; i++) {
+      const element = text[i];
+
+      // avoid any comments like ;#region
+      if (element === ';') {
+        break;
+      }
+
+      if (element === '*') {
+        data.level++;
+      } else {
+        data.name += element;
+      }
+    }
+    if (data.level > 1) {
+      data.kind = vscode.SymbolKind.Function;
+    }
+    data.name = data.name.trim();
+    return data;
+  }
+
+  private createSymbol(block: BlockData): LevelDocumentSymbol {
+    return new LevelDocumentSymbol(
+        block.name,
+        '',
+        block.kind,
+
+        // line number range for entire symbol block
+        new vscode.Range(block.start.range.start, block.end.range.end),
+
+        // where to put line highlighting
+        new vscode.Range(
+            new vscode.Position(
+                block.start.lineNumber,
+                block.level+1,
+            ),
+            new vscode.Position(
+                block.start.lineNumber,
+                block.start.text.length,
+            ),
+        ),
+        block.level,
+    );
+  }
+
+  async provideDocumentSymbols(
+      document: vscode.TextDocument,
+      _token: vscode.CancellationToken,
+  ): Promise<vscode.DocumentSymbol[]> {
+    const allSymbols: LevelDocumentSymbol[] = [];
+    let lineNumber = 0;
+
+    while (lineNumber < document.lineCount) {
+      const currentLine = document.lineAt(lineNumber);
+      lineNumber++;
+
+      // blocks start with 1 or 2 asterisks (*)
+      // https://beancount.github.io/docs/beancount_language_syntax.html#comments
+      if (!currentLine.text.startsWith('*')) {
+        continue;
+      }
+
+      const result: BlockData = this.parseText(currentLine.text);
+
+      if (!result.name) {
+        // detect case where name is not yet provided
+        continue;
+      }
+
+      result.start = currentLine;
+      result.end = currentLine;
+
+      // search for the end of this heading block
+      while (lineNumber < document.lineCount) {
+        const line = document.lineAt(lineNumber);
+        if (!line.text.startsWith('*')) {
+          result.end = line;
+          lineNumber++;
+        } else {
+          break;
+        }
+      }
+
+      // check if this symbol should be a child or not
+      const lastSymbol = allSymbols[allSymbols.length-1];
+      if (lastSymbol && lastSymbol.level < result.level) {
+        lastSymbol.children.push(this.createSymbol(result));
+      } else {
+        allSymbols.push(this.createSymbol(result));
+      }
+    }
+
+    return allSymbols;
+  }
+}