Ignore empty or whitespace-only lines when calculating

Author: lumaxis

src/lib/documentHelpers.ts

@@ -7,9 +7,18 @@ export function linesForIndexes(document: TextDocument, lineIndexes: number[]):
 }
 
 export function minimumIndentationForLineIndexes(document: TextDocument, lineIndexes: number[]): number {
-	const indentationLevels = lineIndexes.map((lineIndex) => {
-		return document.lineAt(lineIndex).firstNonWhitespaceCharacterIndex;
-	});
+	const indentationLevels = lineIndexes.reduce<number[]>((indentationLevels, lineIndex) => {
+		const line = document.lineAt(lineIndex);
+
+		// Skip empty lines so they don't skew the calculation results
+		if (line.isEmptyOrWhitespace) {
+			return indentationLevels;
+		}
+
+		indentationLevels.push(line.firstNonWhitespaceCharacterIndex);
+
+		return indentationLevels;
+	}, []);
 
 	const minimumIndentationLevelInSelection = Math.min(...indentationLevels);
 	return minimumIndentationLevelInSelection;

src/test/fixtures/javascript-example.js

@@ -8,4 +8,9 @@ class MyThing {
   doSomethingElse() {
     throw new Error('Nope!');
   }
+
+    emptyFunction() {
+
+  
+    }
 }

src/test/suite/lib/documentHelpers.test.ts

@@ -36,6 +36,10 @@ describe('Document Helpers', function () {
 		it('calculates the correct minimum indentation level for multiple lines', () => {
 			assert.equal(minimumIndentationForLineIndexes(document, [1, 2, 3]), 2);
 		});
+
+		it('calculates the correct minimum indentation level when lines contain an empty line', () => {
+			assert.equal(minimumIndentationForLineIndexes(document, [11, 12, 13, 14]), 4);
+		});
 	});
 
 	context('contentOfLinesWithAdjustedIndentation', async () => {