feat: generate type imports for readonly visitors

nestjs · Jun 16, 2023 · c82cf93 · c82cf93
1 parent 96945e8
commit c82cf93
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Showing 3 changed files with 67 additions and 6 deletions.
diff --git a/lib/compiler/interfaces/readonly-visitor.interface.ts b/lib/compiler/interfaces/readonly-visitor.interface.ts
@@ -8,6 +8,7 @@ export type DeepPluginMeta =
 
 export interface ReadonlyVisitor {
   key: string;
+  typeImports: Record<string, string>;
   visit(program: ts.Program, sf: ts.SourceFile): void;
   collect(): Record<string, Array<[ts.CallExpression, DeepPluginMeta]>>;
 }
diff --git a/lib/compiler/plugins/plugin-metadata-generator.ts b/lib/compiler/plugins/plugin-metadata-generator.ts
@@ -129,14 +129,20 @@ export class PluginMetadataGenerator {
       }
     }
 
+    let typeImports: Record<string, string> = {};
     const collectedMetadata: Record<
       string,
       Record<string, Array<[ts.CallExpression, DeepPluginMeta]>>
     > = {};
+
     visitors.forEach((visitor) => {
       collectedMetadata[visitor.key] = visitor.collect();
+      typeImports = {
+        ...typeImports,
+        ...visitor.typeImports,
+      };
     });
-    this.pluginMetadataPrinter.print(collectedMetadata, {
+    this.pluginMetadataPrinter.print(collectedMetadata, typeImports, {
       outputDir,
       filename,
     });

diff --git a/lib/compiler/plugins/plugin-metadata-printer.ts b/lib/compiler/plugins/plugin-metadata-printer.ts
@@ -4,21 +4,25 @@ import * as ts from 'typescript';
 import { DeepPluginMeta } from '../interfaces/readonly-visitor.interface';
 
 const SERIALIZED_METADATA_FILENAME = 'metadata.ts';
+const TYPE_IMPORT_VARIABLE_NAME = 't';
 
 export interface PluginMetadataPrintOptions {
   outputDir: string;
   filename?: string;
 }
 
+type ComposedPluginMeta = Record<
+  string,
+  Record<string, Array<[ts.CallExpression, DeepPluginMeta]>>
+>;
+
 /**
  * Prints the metadata to a file.
  */
 export class PluginMetadataPrinter {
   print(
-    metadata: Record<
-      string,
-      Record<string, Array<[ts.CallExpression, DeepPluginMeta]>>
-    >,
+    metadata: ComposedPluginMeta,
+    typeImports: Record<string, string>,
     options: PluginMetadataPrintOptions,
   ) {
     const objectLiteralExpr = ts.factory.createObjectLiteralExpression(
@@ -31,10 +35,24 @@ export class PluginMetadataPrinter {
         ),
       ),
     );
+
     const exportAssignment = ts.factory.createExportAssignment(
       undefined,
       undefined,
-      objectLiteralExpr,
+      ts.factory.createArrowFunction(
+        [ts.factory.createToken(ts.SyntaxKind.AsyncKeyword)],
+        undefined,
+        [],
+        undefined,
+        ts.factory.createToken(ts.SyntaxKind.EqualsGreaterThanToken),
+        ts.factory.createBlock(
+          [
+            this.createTypeImportVariableStatement(typeImports),
+            ts.factory.createReturnStatement(objectLiteralExpr),
+          ],
+          true,
+        ),
+      ),
     );
 
     const printer = ts.createPrinter({
@@ -110,4 +128,40 @@ export class PluginMetadataPrinter {
           ),
     );
   }
+
+  private createTypeImportVariableStatement(
+    typeImports: Record<string, string>,
+  ): ts.Statement {
+    return ts.factory.createVariableStatement(
+      undefined,
+      ts.factory.createVariableDeclarationList(
+        [
+          ts.factory.createVariableDeclaration(
+            ts.factory.createIdentifier(TYPE_IMPORT_VARIABLE_NAME),
+            undefined,
+            undefined,
+            ts.factory.createObjectLiteralExpression(
+              Object.keys(typeImports).map((ti) =>
+                this.createPropertyAssignment(ti, typeImports[ti]),
+              ),
+              true,
+            ),
+          ),
+        ],
+        ts.NodeFlags.Const |
+          ts.NodeFlags.AwaitContext |
+          ts.NodeFlags.ContextFlags |
+          ts.NodeFlags.TypeExcludesFlags,
+      ),
+    );
+  }
+
+  private createPropertyAssignment(identifier: string, target: string) {
+    return ts.factory.createPropertyAssignment(
+      ts.factory.createComputedPropertyName(
+        ts.factory.createStringLiteral(identifier),
+      ),
+      ts.factory.createIdentifier(target),
+    );
+  }
 }