chore(*): organise rules into folders by type

src/rules/line/indentationMultiple.ts

@@ -0,0 +1,41 @@
+import { LintConfig } from '../../types'
+import { LineLintRule } from '../../types/LintRule'
+import { LintRuleType } from '../../types/LintRuleType'
+import { Severity } from '../../types/Severity'
+
+const name = 'indentationMultiple'
+const description = 'Ensure indentation by a multiple of the configured number.'
+const message = 'Line has incorrect indentation'
+const test = (value: string, lineNumber: number, config?: LintConfig) => {
+  if (!value.startsWith(' ')) return []
+
+  const indentationMultiple = isNaN(config?.indentationMultiple as number)
+    ? 2
+    : config!.indentationMultiple
+
+  if (indentationMultiple === 0) return []
+  const numberOfSpaces = value.search(/\S|$/)
+  if (numberOfSpaces % indentationMultiple! === 0) return []
+  return [
+    {
+      message: `${message} - ${numberOfSpaces} ${
+        numberOfSpaces === 1 ? 'space' : 'spaces'
+      }`,
+      lineNumber,
+      startColumnNumber: 1,
+      endColumnNumber: 1,
+      severity: Severity.Warning
+    }
+  ]
+}
+
+/**
+ * Lint rule that checks if a line is indented by a multiple of the configured indentation multiple.
+ */
+export const indentationMultiple: LineLintRule = {
+  type: LintRuleType.Line,
+  name,
+  description,
+  message,
+  test
+}