feat: throw error on duplicate module names in workspace

Similar to how pnpm/yarn workspaces error when multiple packages share the
same name, pgpm now throws a DUPLICATE_MODULE error when getModules() or
listModules() encounters multiple modules with the same .control file name.

Previously getModules() returned all matches (causing duplicate entries in
pgpm deploy's interactive prompt) and listModules() silently picked the
shortest path. Both now throw a descriptive error listing the conflicting
paths.

Author: pyramation

pgpm/core/src/core/class/pgpm.ts

@@ -284,16 +284,29 @@ export class PgpmPackage {
     if (!this.workspacePath || !this.config) return [];
 
     const dirs = this.loadAllowedDirs();
-    const results: PgpmPackage[] = [];
+    const seen = new Map<string, PgpmPackage[]>();
 
     for (const dir of dirs) {
       const proj = new PgpmPackage(dir);
       if (proj.isInModule()) {
-        results.push(proj);
+        const name = proj.getModuleName();
+        if (!seen.has(name)) {
+          seen.set(name, []);
+        }
+        seen.get(name)!.push(proj);
+      }
+    }
+
+    // Error on duplicate module names, similar to pnpm/yarn workspace duplicate package errors
+    const duplicates = Array.from(seen.entries()).filter(([, projs]) => projs.length > 1);
+    if (duplicates.length > 0) {
+      for (const [name, projs] of duplicates) {
+        const paths = projs.map(p => `    - ${p.cwd}`).join('\n');
+        throw errors.DUPLICATE_MODULE({ name, paths });
       }
     }
 
-    return results;
+    return Array.from(seen.values()).map(projs => projs[0]);
   }
 
   /**
@@ -318,17 +331,14 @@ export class PgpmPackage {
       filesByName.get(moduleName)!.push(file);
     });
 
-    // For each module name, pick the shortest path in case of collisions
+    // Error on duplicate module names, similar to pnpm/yarn workspace duplicate package errors
     const selectedFiles = new Map<string, string>();
     filesByName.forEach((files, moduleName) => {
       if (files.length === 1) {
         selectedFiles.set(moduleName, files[0]);
       } else {
-        // Multiple files with same name - pick shortest path
-        const shortestFile = files.reduce((shortest, current) => 
-          current.length < shortest.length ? current : shortest
-        );
-        selectedFiles.set(moduleName, shortestFile);
+        const paths = files.map(f => `    - ${path.dirname(f)}`).join('\n');
+        throw errors.DUPLICATE_MODULE({ name: moduleName, paths });
       }
     });
 

pgpm/types/src/error-factory.ts

@@ -145,6 +145,13 @@ export const errors = {
       `${type ? `${type} file` : 'File'} not found: ${filePath}`,
     404
   ),
+
+  DUPLICATE_MODULE: makeError(
+    'DUPLICATE_MODULE',
+    ({ name, paths }: { name: string, paths: string }) =>
+      `Multiple modules share the name "${name}". Each module in a workspace must have a unique name.\n  Found in:\n${paths}`,
+    400
+  ),
 };
 
 // throw errors.MODULE_NOT_FOUND({ name: 'auth' });