feat: Refine summary message for equal empty data frames (#20)

Author: MariusMerkleQC

diffly/summary.py

@@ -146,9 +146,11 @@ def _print_to_console(self, console: Console) -> None:
             self._print_diff(console)
 
     def _print_equal(self, console: Console) -> None:
-        text = Text(
-            "--- Data frames match exactly! ---", style="green bold", justify="center"
-        )
+        if self._comparison.num_rows_left() == 0:
+            message = "--- Data frames are empty, but their schema matches exactly! ---"
+        else:
+            message = "--- Data frames match exactly! ---"
+        text = Text(message, style="green bold", justify="center")
         text.align("center", console.width)
         console.print(text)
 

tests/summary/fixtures/empty_left_right/gen/pretty_False_perfect_False_top_False_slim_False_sample_rows_False_sample_pk_False.txt

@@ -1,4 +1,4 @@
 ┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
 ┃                                     Diffly Summary                                     ┃
 ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛
-                            --- Data frames match exactly! ---
+             --- Data frames are empty, but their schema matches exactly! ---

tests/summary/fixtures/empty_left_right/gen/pretty_False_perfect_False_top_False_slim_False_sample_rows_True_sample_pk_False.txt

@@ -1,4 +1,4 @@
 ┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
 ┃                                     Diffly Summary                                     ┃
 ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛
-                            --- Data frames match exactly! ---
+             --- Data frames are empty, but their schema matches exactly! ---

tests/summary/fixtures/empty_left_right/gen/pretty_False_perfect_False_top_False_slim_True_sample_rows_False_sample_pk_False.txt

@@ -1 +1 @@
-                            --- Data frames match exactly! ---
+             --- Data frames are empty, but their schema matches exactly! ---

tests/summary/fixtures/empty_left_right/gen/pretty_False_perfect_False_top_False_slim_True_sample_rows_True_sample_pk_False.txt

@@ -1 +1 @@
-                            --- Data frames match exactly! ---
+             --- Data frames are empty, but their schema matches exactly! ---

tests/summary/fixtures/empty_left_right/gen/pretty_False_perfect_False_top_True_slim_False_sample_rows_False_sample_pk_False.txt

@@ -1,4 +1,4 @@
 ┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
 ┃                                     Diffly Summary                                     ┃
 ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛
-                            --- Data frames match exactly! ---
+             --- Data frames are empty, but their schema matches exactly! ---

tests/summary/fixtures/empty_left_right/gen/pretty_False_perfect_False_top_True_slim_False_sample_rows_True_sample_pk_True.txt

@@ -1,4 +1,4 @@
 ┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
 ┃                                     Diffly Summary                                     ┃
 ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛
-                            --- Data frames match exactly! ---
+             --- Data frames are empty, but their schema matches exactly! ---

tests/summary/fixtures/empty_left_right/gen/pretty_False_perfect_False_top_True_slim_True_sample_rows_False_sample_pk_False.txt

@@ -1 +1 @@
-                            --- Data frames match exactly! ---
+             --- Data frames are empty, but their schema matches exactly! ---

tests/summary/fixtures/empty_left_right/gen/pretty_False_perfect_False_top_True_slim_True_sample_rows_True_sample_pk_True.txt

@@ -1 +1 @@
-                            --- Data frames match exactly! ---
+             --- Data frames are empty, but their schema matches exactly! ---

tests/summary/fixtures/empty_left_right/gen/pretty_False_perfect_True_top_False_slim_False_sample_rows_False_sample_pk_False.txt

@@ -1,4 +1,4 @@
 ┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
 ┃                                     Diffly Summary                                     ┃
 ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛
-                            --- Data frames match exactly! ---
+             --- Data frames are empty, but their schema matches exactly! ---