feat(format-diagnostics): add diagnostic information to format result payload

src/format/formatFile.ts

@@ -1,4 +1,6 @@
 import { createFile, readFile } from '@sasjs/utils/file'
+import { lintFile } from '../lint'
+import { FormatResult } from '../types'
 import { LintConfig } from '../types/LintConfig'
 import { getLintConfig } from '../utils/getLintConfig'
 import { processText } from './shared'
@@ -7,16 +9,37 @@ import { processText } from './shared'
  * Applies automatic formatting to the file at the given path.
  * @param {string} filePath - the path to the file to be formatted.
  * @param {LintConfig} configuration - an optional configuration. When not passed in, this is read from the .sasjslint file.
- * @returns {Promise<void>} Resolves successfully when the file has been formatted.
+ * @returns {Promise<FormatResult>} Resolves successfully when the file has been formatted.
  */
 export const formatFile = async (
   filePath: string,
   configuration?: LintConfig
-) => {
+): Promise<FormatResult> => {
   const config = configuration || (await getLintConfig())
+  const diagnosticsBeforeFormat = await lintFile(filePath)
+  const diagnosticsCountBeforeFormat = diagnosticsBeforeFormat.length
+
   const text = await readFile(filePath)
 
   const formattedText = processText(text, config)
 
   await createFile(filePath, formattedText)
+
+  const diagnosticsAfterFormat = await lintFile(filePath)
+  const diagnosticsCountAfterFormat = diagnosticsAfterFormat.length
+
+  const fixedDiagnosticsCount =
+    diagnosticsCountBeforeFormat - diagnosticsCountAfterFormat
+
+  const updatedFilePaths: string[] = []
+
+  if (fixedDiagnosticsCount) {
+    updatedFilePaths.push(filePath)
+  }
+
+  return {
+    updatedFilePaths,
+    fixedDiagnosticsCount,
+    unfixedDiagnostics: diagnosticsAfterFormat
+  }
 }