Transformations: Omit showing base field names when field.name is unique (#104660)

public/app/features/transformers/utils.test.ts

@@ -90,4 +90,25 @@ describe('useAllFieldNamesFromDataFrames', () => {
 
     expect(names).toEqual(['T', 'N', 'S', 'T (A)', 'N (A)', 'S (A)', 'T (B)', 'N (B)', 'S (B)']);
   });
+
+  it('omit base names when field.name is unique', () => {
+    let frames = [
+      toDataFrame({
+        refId: 'A',
+        fields: [
+          { name: 'T', config: { displayName: 't' }, type: FieldType.time, values: [1, 2, 3] },
+          { name: 'N', config: { displayName: 'n' }, type: FieldType.number, values: [100, 200, 300] },
+          { name: 'S', config: { displayName: 's' }, type: FieldType.string, values: ['1', '2', '3'] },
+        ],
+      }),
+      toDataFrame({
+        refId: 'B',
+        fields: [{ name: 'T', config: { displayName: 't2' }, type: FieldType.time, values: [1, 2, 3] }],
+      }),
+    ];
+
+    const names = getAllFieldNamesFromDataFrames(frames, true);
+
+    expect(names).toEqual(['T', 't', 'n', 's', 't2']);
+  });
 });

public/app/features/transformers/utils.ts

@@ -16,7 +16,23 @@ export const getAllFieldNamesFromDataFrames = (frames: DataFrame[], withBaseFiel
   let names = frames.flatMap((frame) => frame.fields.map((field) => getFieldDisplayName(field, frame, frames)));
 
   if (withBaseFieldNames) {
-    let baseNames = frames.flatMap((frame) => frame.fields.map((field) => field.name));
+    // only add base names of fields that have same field.name
+    let baseNameCounts = new Map<string, number>();
+
+    frames.forEach((frame) =>
+      frame.fields.forEach((field) => {
+        let count = baseNameCounts.get(field.name) ?? 0;
+        baseNameCounts.set(field.name, count + 1);
+      })
+    );
+
+    let baseNames: string[] = [];
+
+    baseNameCounts.forEach((count, name) => {
+      if (count > 1) {
+        baseNames.push(name);
+      }
+    });
 
     // prepend base names + uniquify
     names = [...new Set(baseNames.concat(names))];