From 0c97e900fa171a52425c4d4410c30b2df109038e Mon Sep 17 00:00:00 2001
From: Marty Mcfly <test@example.com>
Date: Sat, 4 Apr 2020 18:32:38 +0300
Subject: [PATCH] fix(ts-transform-paths): use fileExists, remove getSourceFile
 #30

---
 .../ts-helpers/src/ImportPathsResolver.ts     |  1 -
 .../src/ImportPathInternalResolver.ts         | 49 +++++++++----------
 packages/ts-transform-paths/src/Types.ts      | 16 +++---
 3 files changed, 29 insertions(+), 37 deletions(-)

diff --git a/packages/ts-helpers/src/ImportPathsResolver.ts b/packages/ts-helpers/src/ImportPathsResolver.ts
index 83229ae..e21c283 100644
--- a/packages/ts-helpers/src/ImportPathsResolver.ts
+++ b/packages/ts-helpers/src/ImportPathsResolver.ts
@@ -58,7 +58,6 @@ export class ImportPathsResolver {
     }
 }
 
-
 function isRelative(fileName: string) {
   return fileName === '.' || fileName.startsWith('./') || fileName.startsWith('../')
 }
diff --git a/packages/ts-transform-paths/src/ImportPathInternalResolver.ts b/packages/ts-transform-paths/src/ImportPathInternalResolver.ts
index ee8fbff..9f1129e 100644
--- a/packages/ts-transform-paths/src/ImportPathInternalResolver.ts
+++ b/packages/ts-transform-paths/src/ImportPathInternalResolver.ts
@@ -1,18 +1,17 @@
-import ts from 'typescript'
 import path from 'path'
 import { ImportPathsResolver } from '@zerollup/ts-helpers'
-import { Config, EmitHost, TransformationContext } from './Types'
+import { Config, EmitHost, Program, TransformationContext } from './Types'
 
-const fileExistsParts = ['.min.js', '.js', ''] as const
+const fileExistsParts = ['.min.js', '.js'] as const
 
-const tsParts = ['.d.ts','.ts', '.tsx', '/index.ts', '/index.tsx', '/index.d.ts', ''] as const
+const tsParts = ['.ts', '.d.ts', '.tsx', '/index.ts', '/index.tsx', '/index.d.ts', ''] as const
 
 export class ImportPathInternalResolver {
   protected resolver: ImportPathsResolver
   protected emitHost: EmitHost | undefined
 
   constructor(
-    protected program: ts.Program | undefined,
+    protected program: Program | undefined,
     transformationContext: TransformationContext,
     protected config: Config
   ) {
@@ -27,36 +26,34 @@ export class ImportPathInternalResolver {
       : undefined
   }
 
+  fileExists(file: string) {
+    const { program, emitHost } = this
+    if (program?.fileExists) return program.fileExists(file)
+    if (emitHost?.fileExists) return emitHost.fileExists(file)
+
+    return true
+  }
+
   resolveImport(oldImport: string, currentDir: string): string | undefined {
-    const { emitHost, config } = this
+    const config = this.config
     const newImports = this.resolver.getImportSuggestions(oldImport, currentDir)
+
     if (!newImports) return
+
     for (let newImport of newImports) {
-      const host = this.program ?? emitHost
-
-      if (host) {
-        let newImportPath = path.join(currentDir, newImport)
-        if (newImportPath[0] === '.') newImportPath = newImportPath.substring(2)
-        for (let part of tsParts) {
-          if (host.getSourceFile(`${newImportPath}${part}`)) return newImport
-        }  
+      const newImportPath = path.join(currentDir, newImport)
+
+      for (let part of tsParts) {
+        if (this.fileExists(`${newImportPath}${part}`)) return newImport
       }
 
-      if (emitHost && emitHost.fileExists) {
-        if (config.tryLoadJs) {
-          for (let ext of fileExistsParts) {
-            const importWithExtension = `${newImport}${ext}`
-            if (emitHost.fileExists(path.join(currentDir, importWithExtension)))
-              return importWithExtension
-          }
-        }
-        if (config.fileCkeckExists) {
-          if (emitHost.fileExists(path.join(currentDir, newImport))) return newImport
+      if (config.tryLoadJs) {
+        for (let ext of fileExistsParts) {
+          if (this.fileExists(`${newImportPath}${ext}`))
+            return `${newImport}${ext}`
         }
       }
 
-      if (!host) return newImport
-
     }
   }
 }
diff --git a/packages/ts-transform-paths/src/Types.ts b/packages/ts-transform-paths/src/Types.ts
index b9aa563..f9bc16d 100644
--- a/packages/ts-transform-paths/src/Types.ts
+++ b/packages/ts-transform-paths/src/Types.ts
@@ -12,19 +12,15 @@ export interface Config {
    * @default false
    */
   tryLoadJs?: boolean
-
-  /**
-   * Use emitHost.fileExists to detect if import file exists. Usable for imports like some/Button.css
-   * @default true
-   */
-  fileCkeckExists?: boolean
 }
 
-export const defaultConfig: Config = {
-  fileCkeckExists: true
-}
+export const defaultConfig: Config = {}
+
+type FileExists = Partial<Pick<ts.ModuleResolutionHost, 'fileExists'>>
+
+export type EmitHost = FileExists
 
-export type EmitHost = ts.ModuleResolutionHost & Pick<ts.Program, 'getSourceFile'>
+export type Program = ts.Program & FileExists
 
 export type TransformationContext = ts.TransformationContext & {
   getEmitHost?: () => EmitHost