refactor(ivy): improve error message in `ngtsc`'s `findExportedNameOfNode()` (#28963)

PR Close #28963

packages/compiler-cli/src/ngtsc/imports/src/emitter.ts

@@ -54,8 +54,8 @@ export interface ReferenceEmitStrategy {
 /**
  * Generates `Expression`s which refer to `Reference`s in a given context.
  *
- * A `ReferenceEmitter` uses one or more `ReferenceEmitStrategy` implementations to produce a
- * an `Expression` which refers to a `Reference` in the context of a particular file.
+ * A `ReferenceEmitter` uses one or more `ReferenceEmitStrategy` implementations to produce an
+ * `Expression` which refers to a `Reference` in the context of a particular file.
  */
 export class ReferenceEmitter {
   constructor(private strategies: ReferenceEmitStrategy[]) {}

packages/compiler-cli/src/ngtsc/imports/src/find_export.ts

@@ -23,9 +23,10 @@ export function findExportedNameOfNode(
   // Look for the export which declares the node.
   const found = exports.find(sym => symbolDeclaresNode(sym, target, checker));
   if (found === undefined) {
-    throw new Error(`failed to find target in ${file.fileName}`);
+    throw new Error(
+        `Failed to find exported name of node (${target.getText()}) in '${file.fileName}'.`);
   }
-  return found !== undefined ? found.name : null;
+  return found.name;
 }
 
 /**