Fix: Correctly locate migrations folder for multi-file Prisma schema

src/__fixtures__/multi-file-schema/schema/post.prisma

@@ -0,0 +1,15 @@
+/// Blog Post
+model Post {
+  /// Post ID
+  postId    Int      @id @default(autoincrement()) @map("post_id")
+  /// Post Title
+  title     String
+  /// Post Content
+  content   String?
+  author    User     @relation(fields: [authorId], references: [userId])
+  /// Author ID
+  authorId  Int      @map("author_id")
+  createdAt DateTime @default(now()) @map("created_at")
+
+  @@map("posts")
+}

src/__fixtures__/multi-file-schema/schema/schema.prisma

@@ -0,0 +1,12 @@
+generator client {
+  provider = "prisma-client-js"
+}
+
+generator comments {
+  provider = "node ./dist/generator.cjs"
+}
+
+datasource db {
+  provider = "postgresql"
+  url      = env("DATABASE_URL")
+}

src/__fixtures__/multi-file-schema/schema/user.prisma

@@ -0,0 +1,13 @@
+/// User
+model User {
+  /// User ID
+  userId    Int      @id @default(autoincrement()) @map("user_id")
+  /// User Name
+  name      String
+  /// Email address
+  email     String   @unique
+  createdAt DateTime @default(now()) @map("created_at")
+  posts     Post[]
+
+  @@map("users")
+}

src/__snapshots__/generator.test.ts.snap

@@ -256,6 +256,89 @@ COMMENT ON COLUMN "shops"."created_at" IS 'Created At';
 "
 `;
 
+exports[`multi-file-schema > comments-latest.json 1`] = `
+"{
+  "posts": {
+    "table": {
+      "tableName": "posts",
+      "comment": "Blog Post"
+    },
+    "columns": [
+      {
+        "tableName": "posts",
+        "columnName": "post_id",
+        "comment": "Post ID"
+      },
+      {
+        "tableName": "posts",
+        "columnName": "title",
+        "comment": "Post Title"
+      },
+      {
+        "tableName": "posts",
+        "columnName": "content",
+        "comment": "Post Content"
+      },
+      {
+        "tableName": "posts",
+        "columnName": "author_id",
+        "comment": "Author ID"
+      },
+      {
+        "tableName": "posts",
+        "columnName": "created_at",
+        "comment": ""
+      }
+    ]
+  },
+  "users": {
+    "table": {
+      "tableName": "users",
+      "comment": "User"
+    },
+    "columns": [
+      {
+        "tableName": "users",
+        "columnName": "user_id",
+        "comment": "User ID"
+      },
+      {
+        "tableName": "users",
+        "columnName": "name",
+        "comment": "User Name"
+      },
+      {
+        "tableName": "users",
+        "columnName": "email",
+        "comment": "Email address"
+      },
+      {
+        "tableName": "users",
+        "columnName": "created_at",
+        "comment": ""
+      }
+    ]
+  }
+}"
+`;
+
+exports[`multi-file-schema > migration.sql 1`] = `
+"
+-- posts comments
+COMMENT ON TABLE "posts" IS 'Blog Post';
+COMMENT ON COLUMN "posts"."post_id" IS 'Post ID';
+COMMENT ON COLUMN "posts"."title" IS 'Post Title';
+COMMENT ON COLUMN "posts"."content" IS 'Post Content';
+COMMENT ON COLUMN "posts"."author_id" IS 'Author ID';
+
+-- users comments
+COMMENT ON TABLE "users" IS 'User';
+COMMENT ON COLUMN "users"."user_id" IS 'User ID';
+COMMENT ON COLUMN "users"."name" IS 'User Name';
+COMMENT ON COLUMN "users"."email" IS 'Email address';
+"
+`;
+
 exports[`multi-schema > comments-latest.json 1`] = `
 "{
   "foo.registered_user": {

src/generator.test.ts

@@ -111,8 +111,27 @@ test("mysql", async () => {
   expect(commentsLatestJsonContent).toMatchSnapshot("comments-latest.json");
 });
 
+test("multi-file-schema", async () => {
+  // Arrange
+  const name = "multi-file-schema";
+
+  // Act
+  executeGenerate(name);
+
+  // Assert
+  const migrationSqlContent = readMigrationSql(name);
+  expect(migrationSqlContent).toMatchSnapshot("migration.sql");
+
+  const commentsLatestJsonContent = readCommentsLatestJson(name);
+  expect(commentsLatestJsonContent).toMatchSnapshot("comments-latest.json");
+});
+
 const executeGenerate = (name: string) => {
-  const schemaPath = path.join(fixturesDir, name, "schema.prisma");
+  // For multi-file-schema, use the schema folder instead of schema.prisma file
+  const schemaPath =
+    name === "multi-file-schema"
+      ? path.join(fixturesDir, name, "schema")
+      : path.join(fixturesDir, name, "schema.prisma");
   child_process.execSync(`npx prisma generate --schema ${schemaPath}`);
 };
 
@@ -155,5 +174,9 @@ const readMigrationSql = (name: string): string => {
 };
 
 const getMigrationsDir = (name: string) => {
+  // For multi-file-schema, migrations are in the schema subfolder
+  if (name === "multi-file-schema") {
+    return path.join(fixturesDir, name, "schema", "migrations");
+  }
   return path.join(fixturesDir, name, "migrations");
 };

src/generator.ts

@@ -17,7 +17,7 @@ import { parse } from "./parser";
 import { generateCommentStatements } from "./statement";
 
 const generate = async (options: GeneratorOptions) => {
-  const { dmmf, schemaPath } = options;
+  const { dmmf } = options;
   const config = readConfig(options);
 
   fs.mkdirSync(config.outputDir, { recursive: true });
@@ -47,7 +47,7 @@ const generate = async (options: GeneratorOptions) => {
   }
 
   const migrationDirName = await outputMigrationFile(
-    path.dirname(schemaPath),
+    config.outputDir,
     commentStatements,
   );
 
@@ -62,7 +62,7 @@ const generate = async (options: GeneratorOptions) => {
 };
 
 const outputMigrationFile = async (
-  baseDirPath: string,
+  migrationsDir: string,
   commentStatements: string[],
 ) => {
   const date = new Date();
@@ -74,7 +74,7 @@ const outputMigrationFile = async (
     .replace(".000", "");
   const dirName = `${dateStr}_update_comments`;
 
-  const migrationDir = path.join(baseDirPath, "migrations", dirName);
+  const migrationDir = path.join(migrationsDir, dirName);
   fs.mkdirSync(migrationDir, { recursive: true });
   fs.writeFileSync(
     path.join(migrationDir, "migration.sql"),