Add TextModel.getLineIndentGuide

src/vs/editor/common/editorCommon.ts

@@ -1574,6 +1574,11 @@ export interface ITextModel {
 	 */
 	getIndentRanges(): IndentRange[];
 
+	/**
+	 * @internal
+	 */
+	getLineIndentGuide(lineNumber:number): number;
+
 	/**
 	 * Get the text for all lines.
 	 */

src/vs/editor/common/model/textModel.ts

@@ -480,11 +480,34 @@ export class TextModel extends OrderGuaranteeEventEmitter implements editorCommo
 		this._indentRanges = null;
 	}
 
-	public getIndentRanges(): IndentRange[] {
+	private _getIndentRanges(): IndentRange[] {
 		if (!this._indentRanges) {
 			this._indentRanges = computeRanges(this);
 		}
-		return IndentRange.deepCloneArr(this._indentRanges);
+		return this._indentRanges;
+	}
+
+	public getIndentRanges(): IndentRange[] {
+		let indentRanges = this._getIndentRanges();
+		return IndentRange.deepCloneArr(indentRanges);
+	}
+
+	public getLineIndentGuide(lineNumber:number): number {
+		if (lineNumber < 1 || lineNumber > this.getLineCount()) {
+			throw new Error('Illegal value ' + lineNumber + ' for `lineNumber`');
+		}
+
+		let indentRanges = this._getIndentRanges();
+
+		for (let i = indentRanges.length - 1; i >= 0; i--) {
+			let rng = indentRanges[i];
+
+			if (rng.startLineNumber < lineNumber && lineNumber <= rng.endLineNumber) {
+				return 1 + Math.floor(rng.indent / this._options.tabSize);
+			}
+		}
+
+		return 0;
 	}
 
 	public getLinesContent(): string[] {

src/vs/editor/test/common/model/textModel.test.ts

@@ -556,3 +556,136 @@ suite('Editor Model - TextModel', () => {
 		model.dispose();
 	});
 });
+
+suite('TextModel.getLineIndentGuide', () => {
+	function assertIndentGuides(lines:[number,string][]): void {
+		let text = lines.map(l => l[1]).join('\n');
+		let model = new TextModel([], TextModel.toRawText(text, TextModel.DEFAULT_CREATION_OPTIONS));
+
+		let actual: [number,string][] = [];
+		for (let line = 1; line <= model.getLineCount(); line++) {
+			actual[line - 1] = [model.getLineIndentGuide(line), model.getLineContent(line)];
+		}
+
+		// let expected = lines.map(l => l[0]);
+
+		assert.deepEqual(actual, lines);
+
+		model.dispose();
+	}
+
+	test('getLineIndentGuide one level', () => {
+		assertIndentGuides([
+			[0, 'A'],
+			[1, '  A'],
+			[1, '  A'],
+			[1, '  A'],
+		]);
+	});
+
+	test('getLineIndentGuide two levels', () => {
+		assertIndentGuides([
+			[0, 'A'],
+			[1, '  A'],
+			[1, '  A'],
+			[1, '    A'],
+			[1, '    A'],
+		]);
+	});
+
+	test('getLineIndentGuide three levels', () => {
+		assertIndentGuides([
+			[0, 'A'],
+			[1, '  A'],
+			[1, '    A'],
+			[2, '      A'],
+			[0, 'A'],
+		]);
+	});
+
+	test('getLineIndentGuide decreasing indent', () => {
+		assertIndentGuides([
+			[0, '    A'],
+			[0, '  A'],
+			[0, 'A'],
+		]);
+	});
+
+	test('getLineIndentGuide Java', () => {
+		assertIndentGuides([
+			[0, 'class A {'],
+			[1, '  void foo() {'],
+			[1, '    console.log(1);'],
+			[1, '    console.log(2);'],
+			[1, '  }'],
+			[1, ''],
+			[1, '  void bar() {'],
+			[1, '    console.log(3);'],
+			[1, '  }'],
+			[0, '}'],
+			[0, 'interface B {'],
+			[1, '  void bar();'],
+			[0, '}'],
+		]);
+	});
+
+	test('getLineIndentGuide Javadoc', () => {
+		assertIndentGuides([
+			[0, '/**'],
+			[1, ' * Comment'],
+			[1, ' */'],
+			[0, 'class A {'],
+			[1, '  void foo() {'],
+			[1, '  }'],
+			[0, '}'],
+		]);
+	});
+
+	test('getLineIndentGuide Whitespace', () => {
+		assertIndentGuides([
+			[0, 'class A {'],
+			[1, ''],
+			[1, '  void foo() {'],
+			[1, '     '],
+			[1, '     return 1;'],
+			[1, '  }'],
+			[1, '      '],
+			[0, '}'],
+		]);
+	});
+
+	test('getLineIndentGuide Tabs', () => {
+		assertIndentGuides([
+			[0, 'class A {'],
+			[1, '\t\t'],
+			[1, '\tvoid foo() {'],
+			[2, '\t \t//hello'],
+			[2, '\t    return 2;'],
+			[1, '  \t}'],
+			[1, '      '],
+			[0, '}'],
+		]);
+	});
+
+	test('getLineIndentGuide checker.ts', () => {
+		assertIndentGuides([
+			/* 1*/[ 0, '/// <reference path="binder.ts"/>'],
+			/* 2*/[ 0, ''],
+			/* 3*/[ 0, '/* @internal */'],
+			/* 4*/[ 0, 'namespace ts {'],
+			/* 5*/[ 1, '    let nextSymbolId = 1;'],
+			/* 6*/[ 1, '    let nextNodeId = 1;'],
+			/* 7*/[ 1, '    let nextMergeId = 1;'],
+			/* 8*/[ 1, '    let nextFlowId = 1;'],
+			/* 9*/[ 1, ''],
+			/*10*/[ 1, '    export function getNodeId(node: Node): number {'],
+			/*11*/[ 2, '        if (!node.id) {'],
+			/*12*/[ 3, '            node.id = nextNodeId;'],
+			/*13*/[ 3, '            nextNodeId++;'],
+			/*14*/[ 2, '        }'],
+			/*15*/[ 2, '        return node.id;'],
+			/*16*/[ 1, '    }'],
+			/*17*/[ 0, '}'],
+		]);
+	});
+});