Ignore single space indents (#31)

fixture/single-space-ignore.js

@@ -0,0 +1,12 @@
+/**
+ *
+ * Long
+ * Multi-line
+ * Single space
+ * Comment
+ *
+ */
+
+    4 spaces
+    4 spaces
+	1 tab

fixture/single-space-only.js

@@ -0,0 +1,3 @@
+ 1 space
+ 1 space
+ 1 space

index.js

@@ -15,7 +15,7 @@ const INDENT_TYPE_TAB = 'tab';
 //    s5: [1, 0],
 //   s12: [1, 0],
 // }
-function makeIndentsMap(string) {
+function makeIndentsMap(string, ignoreSingleSpaces) {
 	const indents = new Map();
 
 	// Remember the size of previous line's indentation
@@ -49,6 +49,11 @@ function makeIndentsMap(string) {
 				indentType = INDENT_TYPE_TAB;
 			}
 
+			// Ignore single space unless it's the only indent detected to prevent common false positives
+			if (ignoreSingleSpaces && indentType === INDENT_TYPE_SPACE && indent === 1) {
+				continue;
+			}
+
 			if (indentType !== previousIndentType) {
 				previousSize = 0;
 			}
@@ -129,7 +134,13 @@ module.exports = string => {
 		throw new TypeError('Expected a string');
 	}
 
-	const indents = makeIndentsMap(string);
+	// Identify indents while skipping single space indents to avoid common edge cases (e.g. code comments)
+	// If no indents are identified, run again and include all indents for comprehensive detection
+	let indents = makeIndentsMap(string, true);
+	if (indents.size === 0) {
+		indents = makeIndentsMap(string, false);
+	}
+
 	const keyOfMostUsedIndent = getMostUsedKey(indents);
 
 	let type;

test.js

@@ -120,3 +120,21 @@ test('return indentation stats for indented files with spaces and tabs last', t
 		type: 'tab'
 	});
 });
+
+test('detect the indent of a file with single line comments', t => {
+	const stats = detectIndent(getFile('fixture/single-space-ignore.js'));
+	t.deepEqual(stats, {
+		amount: 4,
+		indent: '    ',
+		type: 'space'
+	});
+});
+
+test('return indentations status for indented files with single spaces only', t => {
+	const stats = detectIndent(getFile('fixture/single-space-only.js'));
+	t.deepEqual(stats, {
+		amount: 1,
+		indent: ' ',
+		type: 'space'
+	});
+});