refactor: first step toward ESLint 10 support

.changeset/some-moments-trade.md

@@ -0,0 +1,9 @@
+---
+"eslint-plugin-import-x": patch
+---
+
+First step toward ESLint 10 support:
+
+- `sourceType` determination now prefers `context.languageOptions` when possible
+- Ensure `context.parserOptions` no longer results in crashes with ESLint 10
+- Merge `getParser` and `getParserPath` implementations into one `getParserOrPath`

src/utils/parse.ts

@@ -1,4 +1,4 @@
-import path from 'node:path'
+import nodePath from 'node:path'
 
 // import { withoutProjectParserOptions } from '@typescript-eslint/typescript-estree'
 import type { TSESLint, TSESTree } from '@typescript-eslint/utils'
@@ -81,7 +81,7 @@ export function parse(
   let parserOptions =
     context.languageOptions?.parserOptions || context.parserOptions
 
-  const parserOrPath = getParser(path, context)
+  const parserOrPath = getParserOrPath(path, context)
 
   if (!parserOrPath) {
     throw new Error('parserPath or languageOptions.parser is required!')
@@ -165,19 +165,30 @@ export function parse(
   throw new Error('Parser must expose a `parse` or `parseForESLint` method')
 }
 
-function getParser(path: string, context: ChildContext | RuleContext) {
-  const parserPath = getParserPath(path, context)
-
-  if (parserPath) {
-    return parserPath
+function getParserOrPath(path: string, context: ChildContext | RuleContext) {
+  const parsers = context.settings['import-x/parsers']
+  if (parsers != null) {
+    const extension = nodePath.extname(path) as FileExtension
+    for (const parserPath in parsers) {
+      if (parsers[parserPath].includes(extension)) {
+        // use this alternate parser
+        log('using alt parser:', parserPath)
+        return parserPath
+      }
+    }
+  }
+  // default to use ESLint parser, only exists in eslintrc
+  if ('parserPath' in context && context.parserPath) {
+    log('using context.parserPath:', context.parserPath)
+    return context.parserPath
   }
 
   const parser = 'languageOptions' in context && context.languageOptions?.parser
 
   if (
     parser &&
     typeof parser !== 'string' &&
-    (('parse' in parser && typeof parse === 'function') ||
+    (('parse' in parser && typeof parser.parse === 'function') ||
       ('parseForESLint' in parser &&
         typeof parser.parseForESLint === 'function'))
   ) {
@@ -186,19 +197,3 @@ function getParser(path: string, context: ChildContext | RuleContext) {
 
   return null
 }
-
-function getParserPath(filepath: string, context: ChildContext | RuleContext) {
-  const parsers = context.settings['import-x/parsers']
-  if (parsers != null) {
-    const extension = path.extname(filepath) as FileExtension
-    for (const parserPath in parsers) {
-      if (parsers[parserPath].includes(extension)) {
-        // use this alternate parser
-        log('using alt parser:', parserPath)
-        return parserPath
-      }
-    }
-  }
-  // default to use ESLint parser
-  return context.parserPath
-}

src/utils/source-type.ts

@@ -4,10 +4,22 @@ export function sourceType<
   MessageIds extends string,
   Options extends readonly unknown[],
 >(context: TSESLint.RuleContext<MessageIds, Options>) {
-  if ('sourceType' in context.parserOptions) {
-    return context.parserOptions.sourceType
-  }
   if ('languageOptions' in context && context.languageOptions) {
-    return context.languageOptions.sourceType
+    if (
+      'parserOptions' in context.languageOptions &&
+      context.languageOptions.parserOptions?.sourceType
+    ) {
+      return context.languageOptions.parserOptions.sourceType
+    }
+    if (
+      'sourceType' in context.languageOptions &&
+      context.languageOptions.sourceType
+    ) {
+      return context.languageOptions.sourceType
+    }
+  }
+  // For backwards compatibility with earlier ESLint versions without `languageOptions`.
+  if ('parserOptions' in context && context.parserOptions) {
+    return context.parserOptions.sourceType
   }
 }